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Geography

UNIVERSE, EARTH AND THE

SOLAR SYSTEM

The solar system consists of eight

planets, with the sun at its center. These

eight planets revolve around the sun in a

definite path. The eight planets are:

MERCURY:

The first planet positioned near the sun, smallest planet.

The day temperature in this planet

rises to a maximum of 3500C.

At night the temperature goes down

to a minimum of - 1700C. This planet

is unable to hold the heat it receives

during the daytime because of the

absence of Atmosphere.

UNIVERSE, EARTH AND

THE SOLAR SYSTEM

This is the swiftest planet of the solar

family. It has the shortest period to

orbit the sun.

No satellites

Second densest planet after earth.

VENUS - Shining Planet

Venus is positioned second from the

sun and it is next to Mercury.

Hottest Planet

The maximum temperature of

this planet is about 4800C. This

planet records the highest degree

of temperature in the entire

solar system. Because 98% of its

atmosphere is covered by CO2.

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Because of its proximity to the earth

Venus can usually be seen, before

down as the ‘Morning Star’ in the

eastern sky. Likewise, the after

sunset the same planet shines as

brightly as an ‘Evening Star’ in the

western sky.

This is the only planet of the solar

family that rotates from east to

west.

No Satellites

It is also called as earth’s twin

(similar to earth in radius, mass &

density)

Nearest planet to earth.

EARTH

Earth is positioned third from the

sun.

Water accounts for 71% and land

29% of the total area of the earth.

There are seven continents and four

oceans on the surface of earth.

Seven Continents:

(Areawise descending order)

1. Asia (Largest)

2. Africa

3. North America

4. South America

5. Europe

6. Antarctica

7. Australia (Smallest)

OCEANS:

1. Pacific Ocean 2. Atlantic Ocean

3. Indian Ocean

4. Arctic Ocean

The land, water, air and the favourable

climate facilitate the origin of life

in the Earth. Thus the earth is also

known as Living planet.

No other planet of the solar family

has life like that of the earth.

Its only satellite is Moon. It take

365.25 days to around the sun.

From radio active dating, the earth’s

age is estimated to be 4.6 × 109 grs.

The moon keeps the same face turned

towards us:

Because the moon’s axial rotation period

is the same as that of the period of

revolution round the earth i.e. about 27

days 7¾ hrs.

Seasonal Changes are due to:

(i) Revolution of the earth

(ii) Direction of the Earth’s tilt changes

in relation to earth.

Rotation :

Mean solar day: time interval from one noon to the next, about 24hrs.

Sidereal day : time it takes for earth to make one complete (3600) rotation

with respect to a star other than the

sun 23 hrs, 56 min, 4 seconds.

Full moon - 14¾ day.

New Moon again → 29½ day based

on the cycle of the moon’s phases

(synodic month)

Day 27 ⅓ → Earth, Moon and distant

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star are once again aligned

(sidereal month)

↓ True period of the moon’s revolution

around earth

MARS - (Red planet)

230C temperature prevails during

day time and about - 1010C during

night.

Dry rivers, extinct volcanoes, stormy

deserts, snow covered poles are

discovered on the surface of this

planet. Though these features look

similar to these of the earth, they do

not possess greenery like the earth.

Only dry landscape is present all over

this planet.

High amount of iron oxides (fenic

oxides) are found in the soils and

the rocks of this planet. It appears

Reddish. Hence called as Red planet.

There are stormy winds with a speed

of 270 km/hr that blow for months

together. They create a dusty layer

making the planet appearing red.

Satellite : Deimos, phobos - It is

smaller than the earth. Has very thin

atmosphere and a very small amount

of oxygen.

JUPITER

One special feacture of Jupiter is the

great ‘Redspot’. Satellites: Ganemade,

IO, Europa, Callisto - Ganymade dis the

Largest satellite in the solar system.

It is very cold because of its distance

from the sun.

Biggest planet of the solar family. 10th

of the size of the sun.

It has almost perpendicular axis. It

rotates on its axis with an inclination

of about only 2O and hence the planet

does not have any season like the

Earth.

It has highest number of satellites in

the solar system.

Its upper cloud layers seem to

have ammonia & methane, both

poisonous gases.

Fastest rotating planet

It is interesting to astromers because

it sends strong burst of Radiowaves

which may be the result of tremondous

storm on its surface.

SATURN (6th Planet from the sun)

Second largest planet.

There are seven rings around this

planet. This planet, with its 7 multi

coloured rings, appears very elegant.

Cyclonic winds of 1500 km/hr blow

on this planet.

It is the least dense planet in our

solar system.

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Its specific gravity is less than. Water (0.7) If a large ocean where

available Saturn would float in it.Statellite - Titan, Tethys

URANUS

It is positioned seventh from the sun.

Its axis is tilted about 98O to the

vertical plane.

It rolls on its sides while revolving

around the sun but it does not spin

at a top like other planets.

It occurs in this planet.

Rotates from east to west.

Satellites : Miranda, Ariel, Titania, Oberon.

NEPTUNE

Dark - It takes almost 165 earth years

to orbit our sun. Very cold and whipped by

supersonic winds.

Neptune and Pluto are much bigger in

size than the earth. They appear in blue

because of the presence of methane gas

in their atmosphere

It is positioned eight from the sun.

This planet has not completed a

single orbit of the sun since it was

identified in the year 1846.

It appears blue in colour because

of presence the methane gas in the

atmosphere.

Satellite - Triton

Among the planets of the solar system,

except for Mercury and Venus the

rest have satellites of their own.

Jupiter is the swiftest rotating

planet and the slowest is Venus.

Mercury is the swiftest revolving

planet while the slowest is Pluto.

Pulto, Eris and the astenoid ceres

became the first dwarf planets. Unlike planets, dwarf planets lack

the gravitation muscle to sweep up or

scatter objects near their orbits.

S.No. Planet Period

of

Rotation

Period of

Revolution

1. Mercury 58 ½

Days

88 days

2. Venus 243 days 224 days

3. Earth 24 hrs 365 ¼

days

4. Mars 24 ½

days

687 days

5. Jupiter 10 hrs 12 years

6. Saturn 10 ¾ hrs 29 ½ yrs

7. Uranus 17 ¼ hrs 84 years

8. Neptune 16 hrs 165 yrs

9. Pluto 6.4 days 248 yrs

There are millions of stars visible from

the Earth. The closest star is the Sun. The

closest to the Earth, after the Sun, is Alpha

centuria. The main difference between a

planet and a star is that, a star twinkles

and a planet will glow without any flicker.

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Planets:

The eight planets are classified in to Solid planets and Gaseous planets

SOLID PLANETS Mercury, Venus,

Earth, Mars

GASEOUS

PLANETS

Jupiter, Saturn,

Uranus, Neptune

Planets like Mercury, Venus, Mars,

Jupiter and Saturn can be seen with the

naked eye, whereas Uranus and Neptune

can be seen only through a telescope.

Venus and Mercury can be seen before

sunrise and sunset for a few hours. Mars,

Jupiter and Saturn can be seen during the

night either in the east or overhead or in

the west.

During the formation of the Universe, the

planets closes to the Sun experienced

greater solar winds. Due to this the

gaseous contents in these planets got

blown away. On the contrary, the planets

away from the sun did not experience

the solar winds and thus, they’re called

gaseous planets

Venus rises a few hours before

sunrise and therefore it is called as The

Morning Star.

Planet Earth is the known planet to

support different forms of life. This is due

to the earth’s atmosphere, which contains

Oxygen. All other planets have no oxygen

and have large amount of other gases

and have hence life is not found on other

planets. Every planet revolves in an anti-

clockwise direction if you take a bird’s eye

view from the north pole of the sun, but

the duration of their revolution around the

Sun differs from one another. All planets

revolve in an elliptical path in definite paths called Orbits.

Dwarf Planets: (Grouped in 2006)

They also revolve around the Sun.

They are very small in size. Their size is

very smaller than our moon.

Pluto, Charon, Eris, Ceres belong to

this group.

Sun:

The sun is the head of the solar family.

It is the large gaseous ball of fire. The gravity of the sun holds the solar system

together. It is the source of heat and light

to the entire solar family. The Earth is

approximately 150 million Kms away from

the Sun. The Sun is the only celestial body

that emits light in the solar system.

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Eclipses:

When the visibility of a celestial body is

prevented by the passage of a second

body, the occurrence is called as

an eclipse.

Lunar Eclipses:

At the time of full moon, the moon

may pass through the long shadow

cast by the earth in space.

The lunar eclipse can last as long as

3hrs and 40 min. Totality may be upto

1 hr and 40 minutes. If the moon is

nearer the earth (perigee) the eclipse

will last longer. At apogee, the eclipse

will be of a shorter duration.

The eclipse of the moon can occur only

at the time of the full moon, When the

earth comes in between the moon and

the sun.

But the eclipse does not occur at every

full moon. The moon usually passes

above or below the earth’s shadow

because the path it follows is at a slight

angle of about 50 to the ecliptic.

If the moon revolved around the earth

the same plane as that in which the

earth revolves around the sun, there

would be a lunar eclipse every full

moon day.

Solar Eclipse

On New Moon day, the moon comes in

between the sun and the earth. If their

centres are is one line, the moon’s

shadow is cast on the earth.

To an observer the disc of the sun will

appear completely covered by the disc

of the moon.

The solar eclipse lasts for a few minutes

and is seen over a small area.

Total eclipse rarely lasts over 7

minutes and never last more than 8

minutes at any place on the earth.

During the brief period of the total

solar eclipse all direct sunlight is cut

off from the earth. There is

complete darkness in the area of

totality.

The moon’s orbit is inclined at an

angle of 50 9’to the ecliptic. An eclipse

does not occur at every new

moon. Generally the lunar shadow

passes above or below the earth.

Asteroids:

Asteroids are clusters of celestial

bodies which includes tiny stones and big

rocks which can measure upto 300 to 400

Kms in diameter. Thousands of asteroids

are found between Mars and Jupiter.

Asteroids with Tamil name: VynuPappu,

Sarabai, Ramanuja

Moon:

The Moon does not revolve around the

Sun. It revolves around the Earth. Hence,

it is a satellite. The Moon measures the

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quarter of the Earth’s diameter. It revolves

around the Earth at approximately at a

distance of 3,84,401Kms. It takes 27.3

days for the Moon to revolve around the

Earth and to rotate on its axis. Other

planets also have their respective natural

satellites.

Planets Mercury Venus Earth

No. of

Satellites

0 0 1

Planets Mars Jupiter Saturn

No. of

Satellites

2 63 60

Planets Uranus Neptune

No. of

Satellites

27 13

The Moon does not have an atmosphere

as Earth. Water is not explicitly present

in the Moon, but water is available in

the form of moisture. Landforms such as

mountains, plateaus and valleys are found

in the surface of the Moon. Craters are

another special feature of the Moon. Few

craters are volcanic in origin and few are

made due to the impact of the meteorites

on the landscape of the Moon.

The Moon is similar to the earth; it just

reflects the light energy obtained from the Sun. Only a part of the Moon is visible to

the Earth. During the revolution of the

Moon around the Earth, the dark side of

the Moon that faces the Earth is called

the New Moon. The side of the Moon that

shines brightly is called the Full Moon.

Meteoroids and Meteors:

The remains of some rocky asteroids

make their way towards the Earth. The

particles which are burnt by the friction

caused in the atmosphere are called

meteorites. Some particles withstand

the friction of the atmosphere and reach

the surface of the Earth. They are called

meteors.

Comet:

A comet is not a star. It is a rock made

of dust and ice. The comet has a long

reflective tail.How the tail appears? Minute particles

from the Sun strike the gaseous part

emitted from the comet.

What makes the tail reflective? As

the comet comes near the Sun and the ice

melts and reflects the light of the Sun.

Universe:

Millions of constellation of stars seen in

the sky is called the Galaxy. Thousands of

galaxies form a Universe. The Universe is

vast and ever expanding.

There are so many stars seen in the

sky, they are too far from us. These stars

are thousand times bigger than our sun. A

white streak of light can be seen on a clear

night. Our ancestors called it “Akash

Ganga.”

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WEATHER AND CLIMATE:

Weather and Climate are two terms

which are are used in day-to-day life. This

is because our daily routine is based on

the prevailing weather conditions. Human

activity of any region is determined by

weather and climate. Our food habits,

customs, traditions and even most of our

common celebrations are associated with

weather and climate.

Weather:

Weather refers to the physical state of

the atmosphere within 24 hours, described

by weather elements such as temperature,

atmospheric pressure, humidity, rainfall,

cloudiness, wind speed and wind direction.

These differences are the outcome of the

angle of the sun at any particular spot,

which vary by latitude of the tropics.

Climate:The word climate is defined as the

weather averaged over a long period of

time and over a large area. The standing

average period is 30 years.

Factors determining Weather and

Climate:

Day-to-day factors affect the weather

element. The following factors affect the

climate of the place.

1. Latitude: The equator receives vertical

rays which fall over a small area. In

contrast, the polar regions receive

slanting sunrays and they fall over a

CLIMATOLOGY

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wide area. As a result of this, places

near the equator are hotter than the

poles.

Normal Lapse Rate:

Temperature decreases as altitude

increases.This occurs at a rate of 1

degree Celsius/ 165 meters, which is

6.5 degree Celsius per kilometer.

2. Altitude: The places located on high

altitudes are always colder than their

counter parts in the lower altitudes.

This is because the air becomes

thinner as altitude increases and they

absorb only less heat.

3. Distance from the sea: The

Sea absorbs and retains heat for

long duration. The coastal areas

experience the cool, wet air from

the sea throughout the year along

the coast to have uniform weather

both in the winter and summer this

condition is said to be an equtable

climate or maritime climate. On the

other hand, the land absorbs and

loses heat quickly. The interior land

areas experience warm dry air. They

are very hot in summer and very cold

in winter. This condition is said to be

continental climate.

4. Ocean currents: Based on

temperature, the ocean currents are

classified as warm ocean currents and cold ocean currents. Warm currents

make the coastal area warm, wet, and

free from ice. On the contrary, cold

current makes the coastal area cool,

dry and bring in icebergs.

5. Direction of prevailing winds: The

winds that blow from the sea to land

contain more moisture so they are cool

and wet. On the other hand, the winds

blowing from land are warm and dry.

6. El Nino effect: El Nino is formed

during Christmas time and continues

for a few months. During this

period, once in five or six years, the

temperature raises rapidly and

a low pressure system is formed

along the coast of Peru and

Ecuador. This low pressure system

attracts the winds from all directions.

So, the trade winds become weak over

the Indian ocean and the Pacific ocean and these winds are deflected causing a prolonged dry periods in many parts

of the world.

7. Human influence: As a result of

Industrial revolution, forest areas

have been cleared and we have many

types of transport facilities, concrete

buildings and many industries. All

these developments made our life

easy and comfortable. On the other

hand, their effects are felt in the name

of global warming, greenhouse effect

and pollution, which have increased

the amount of CO2. Creation of

urabn heat island is also an effect

of human influence. These islands occur in metropolitan areas, which

are significantly warmer than their surrounding areas.

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ATMOSPHERE

Air is essential to the survival of all

organisms. Some organisms like humans

can survive without the food and water but

not without breathing the air. Atmosphere

is a mixture of gases and it envelopes the

earth all around. It contains life giving

gases. The air is an integral part of the

mass of the earth and 99% of the total

mass of the atmosphere is confined to 32 Km from the earth’s surface.

Composition of the atmosphere:

The atmosphere is a mixture of gases,

water vapour and dust particles. The

proportion of gases changes in higher

layers of the atmosphere. The quantity of

oxygen is negligible as we go to the higher

layers and similarly carbon dioxide and

water is found only upto 90 km from the

surface of the earth.

Constituent Percentage by

volume

Nitrogen 78.08

Oxygen 20.95

Argon 0.93

Carbon dioxide 0.036

Neon 0.002

Helium 0.0005

Krypton 0.001

Xenon 0.00009

Hydrogen 0.00005

There are four major layers of the

atmosphere. They are troposphere,

stratosphere, ionosphere and

exosphere.

Troposphere: Troposphere begins at

the surface of the earth and extends up

to 8 kms at the poles and 18 kms at the

equator. This layer is known for all kind

of weather changes such as temperature,

pressure, winds, cloud formation and

rainfall. In this layer alone, the temperature

decreases with increasing height. The

tropopause is a thin layer that lies between

the troposphere and the stratosphere.

Structure of the Atmosphere

Stratosphere:

Stratosphere extends approximately

for about 50 km. Temperature increases

with height. This is the layer where

most jet planes fly, owing to the lack for weather phenomena. The top edge of the

stratosphere is rich in Ozone (20-50). They

capture the harmful ultraviolet rays from

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the sun, making the light reaching the

earth’s surface harmless. Since unfiltered radiation from the sun can destroy all

animal tissue, Ozone is very important

to all living things on earth. This zone

is also called as isothermal layer and

ozonosphere. After the stratosphere, there

is again a buffer layer called stratopause.

Mesosphere: It extends approximately

for about 80 km.

Ionosphere: Ionosphere stretched from

80 kms- 500 kms. It is called ionosphere

because in this part of the atmosphere

the sun’s radiations gets ionized. It

reflects the radio waves back to the earth which help in modern communications.

The colorful display of auroras are called

the northern lights or aurora borealis

in the northern hemisphere and southern

lights or aurora australis in the

southern hemisphere.

Exosphere: The exosphere is the

uppermost layer of the atmosphere. The

main gases within the exosphere are the

lighter gases, mainly hydrogen and helium.

The exosphere is sometimes considered a

part of outer space.

TEMPERATURE

DISTRIBUTION

The sun is the source of light and

heat to the earth. Earth receives only a

small amount of solar radiation which

takes eight minutes to reach the earth’s

surface. Incoming solar radiation is

called insolation. Heat energy from solar

radiation is received by Earth through

three mechanisms. They are: i) radiation

in the atmosphere ii) Conduction over

land and iii) Convection in the water

bodies. The Earth’s atmosphere is heated

more by terrestrial radiation than by the

insolation.

Factors controlling the temperature

distribution:

a) The latitude: The temperature of

a place depends on the insolation

received. Insolation varies

according to the latitude of the

place hence temperature also varies

accordingly.

b) The Altitude: The atmosphere

is indirectly heated by terrestrial

radiation from below. Therefore,

the places near sea level record

higher temperature than the places

situated in higher altitudes. In other

words, temperature decreases with

increase in height. This is called

Normal Lapse Rate. It is 6.5 degree

Celsius per 1000 meters.

c) Distance from the sea:

Another factor that influences the temperature is the location

of a place with respect to the sea.

Compared to land, the sea gets

heated slowly. Land heats up and

cools down quickly. Therefore, the

variation in temperature over the

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sea is less compared to land. The

places situated near the sea come

under the moderating influencing of the sea and land breeze which

moderate temperature.

d) Air-mass and ocean currents:

Like the land and sea breezes,

the passage of air masses also

influences the temperature of a land mass. The places which come under

the influence of warm air mass experience high temperatures and

the places which come under the

influence of cold air mass experience low temperatures. Similarly, the

places located on the coast where

the warm ocean currents flow records higher temperature than

the places located on the coast

where cold currents flow. e) Direction of Prevailing winds :

The winds that blow from the sea

contain more moisture so they are

cool and wet and cause rainfall

Ex - Southwest Monson

The winds that blow from the

land areas are warm and dry

(No Rainfall)

Ex - North East Monsoon

f) ELNINO Effect : It is warm

oceanic current.

g) HumanInfluence: Deforestation

and human development are felt in

the name of Global warming. Green

house effect, and pollution, which

have increased the amount of Co2.

Distribution of Temperature:

The global distribution of temperature

can well be understood by studying the

temperature distribution in January

and July. The temperature distribution

is generally shown on the map with the

help of isotherms. The Isotherms are lines

joining places having equal temperature.

The above figures show the distribution of surface air temperature in the

Month of January and July.

In general the effect of the latitude

on temperature is well pronounced on

the map, as the isotherms are generally

parallel to the latitude. The deviation from

this general trend is more pronounced in

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January than in July, especially in the

northern hemisphere. In the northern

hemisphere the land surface area is much

larger than in the southern hemisphere.

Hence, the effects of land mass and the

ocean currents are well pronounced.

In January the isotherms deviate to

the north over the ocean and to the

south over the continent.

Daily range of temperature:

The differences between the maximum

and minimum temperatures of a

day is called the diurnal range of

temperature.

It is Low in Equator. It is high in

Desert Areas and tropical interior

land during summer.

Mar 21 - Vernal Equinox

June 22 - Summer Solstice

Sep 23 - Autumnal Equinox

Dec 22 - Winter Solstice

Annual range of temperature:

The differences between Mean

temperature of the hottest and

coldest months of the year is known

as annual range of temperature.

It is very less in equatorial region.

The range is increases from Equator

to subpolar region.

It is high in Desert regions.

Inversion of Temperature:

Normally, temperature decreases with

increase in elevation. It is called normal

lapse rate. At times, the situation is reversed

and the normal lapse rate is inverted. It is

called inversion of temperature. Inversion

is usually of short duration.

A long winter night with clear skies

and still air is ideal situation of inversion.

The heat of the day is radiated off during

the nights and by early morning hours,

the earth is cooler than the air above.

Over polar areas, temperature inversion is

normal throughout the year.

Surface inversion promotes stability in

the lower layers of the atmosphere. Smoke

and dust particles get collected beneath

the inversion layer and spread horizontally

to fill the lower strata of the atmosphere. Dense fogs in the mornings are common

occurrences during the winter season.

This lasts till the sun comes up and warms

up the earth.

The inversion which takes place in hills

and mountains is due to air drainage. Cold

air at the hills and mountains, produced

during night, flow under the influence of gravity. Being heavy and dense, the cold

air moves down and piles up in the pockets

and valley bottoms with warm air above.

This is called air drainage. It protects

plants from frost damages.

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PRESSURE BELTS

Air pressure is defined as the pressure thrust by the weight of the air on the

earth’s surface. The average air pressure

at the sea level is 1,013 millibars. The

horizontal distribution of the air pressure

is highly influenced by the temperature of a given place. The atmospheric pressure is

always inversely related to the atmospheric

temperature. The high pressure belts are

formed in the areas of low temperature.

a) Equatorial Low Pressure Belt:

This belt lies between 5°N and

5°S. The sunrays are vertical over

here throughout the year. Since

temperature is high, the air become

slighter and ascending. It causes

low pressure conditions. This zone

is otherwise called as “a belt of

Calm” or “Doldrums”.

b) Subtropical High Pressure

Belt: This zone lies between 25°

and 35° latitudes in both the

hemispheres. The ascended air

from the tropics is getting cooled

due to low temperature so the

air descends at about 30°- 35°

latitudes. In ancient times, the

merchants carrying horses in their

ships had to throw some of them

out while passing through this

zone of the calm in order to lighten

the ship. Hence, this zone is called

“horse latitudes”.

c) Sub polar Low Pressure Belt: This

belt lies between 60°- 65° latitudes

in both the hemispheres and the

air spreads outward from this zone

due to the rotation of the earth so

the low pressure is produced.

d) Polar High Pressure Belt: This

pressure belt persists at the poles.

The sunrays fall very slanting

at the poles and as a result the

temperature is low and heavy air

accumulates and produces high

pressure.

e) General circulation of the

atmosphere

The pattern of planetary winds

largely depends on:

(i) Latitudinal variation of

atmospheric heating;

(ii) Emergence of pressure belts;

(iii) The migration of belts following

apparent path of the sun;

(iv) The distribution of continents

and oceans;

(v) The rotation of earth.

The air in horizontal motion is called

wind. The air generally moves from high

pressure area to the low pressure area. The

speed of the wind is generally mentioned

in kilometers or miles at land and in knots

at sea.

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WINDS: CYCLONES AND

ANTI CYCLONES:

Planetary Winds:

The winds that blow from a particular

direction throughout the year are known

as the planetary winds. The pattern of the

movement of the planetary winds is called

the general circulation of the atmosphere.

The general circulation of the atmosphere

also sets in motion the ocean water

circulation which influences the earth’s climate.

Ferrels’s law

All moving bodies like wind and ocean

currents get deflected from their normal paths towards right in the

northern hemisphere and towards

left in the southern hemisphere due

to the rotation of the earth. (coriolis

force)

Coriolis force is zero in Equator.

It is increasing from Equator to

poles. So the rate of deflection also increases with the distance from the

Equator.

WINDS

Planetary Winds

Trade Winds

Westerlies

Polar Winds

Seasonal & Periodic

Winds

Monsoon Winds

Land Breeze

Sea Breeze

Local Winds

They are called

different names in

different places.

Variable Winds

Cyclones

Anticyclones

Simplification general circulation of the atmosphere

The air at the Inter Tropical Convergence

Zone (ITCZ) rises because of convection

caused by high insolation and a low

pressure is created. The winds from the

tropics converge at this low pressure zone.

The converged air rises along with the

convective cell. It reaches the top of the

troposphere up to an altitude of 14 km.

and moves towards the poles. This causes

accumulation of air at about 30 degree N

and S. Part of the accumulated air sinks

to the ground and forms a subtropical

high. Another reason for sinking is the

cooling of air when it reaches 30 degree N

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and S latitudes. Down below near the land

surface the air flows towards the equator as the easterlies. The easterlies from either

side of the equator converge in the Inter

Tropical Convergence Zone (ITCZ). Such

circulations from the surface upwards and

vice-versa are called cells. Such a cell in

the tropics is called Hadley Cell.

In the middle latitudes the circulation

is that of sinking cold air that comes from

the poles and the rising warm air that

blows from the subtropical high. At the

surface these winds are called westerlies

and the cell is known as the Ferrel cell.

At polar latitudes the cold dense air

subsides near the poles and blows towards

middle latitudes as the polar easterlies.

This cell is called the Polar cell.

These there cells set the pattern for the

general circulation of the atmosphere.

The transfer of heat energy from lower

latitudes to higher latitudes maintains

the general circulation.

The general circulation of the

atmosphere also affects the oceans. The

large-scale winds of the atmosphere

initiate large and slow moving currents

of the ocean. Oceans in turn provide

input of energy and water vapour into the

air. These interactions take place rather

slowly over a large part of the ocean.

Seasonal and Periodic Winds:

Differences in the heating and cooling

of earth surfaces and the cycles those

develop daily or annually can create

several common, local or regional winds.

Land and Sea Breezes:

Sea Breeze

Land Breeze

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Geography

The land and sea absorb and transfer

heat differently. During the day the land

heats up faster and becomes warmer than

the sea. Therefore, over the land the air

raises giving rise to a low pressure area,

whereas the sea is relatively cool and the

pressure over sea is relatively high. Thus,

pressure gradient from sea to land is

created and the wind blows from the sea

to the land as the sea breeze. In the night

the reversal of this condition takes place.

The land loses heat faster and gets cooler

than the sea. The pressure gradient is

from the land to the sea and hence land

breeze results.

Mountain and Valley Winds:

In mountainous regions, during the

day the slopes get heated up and air

moves upslope and to fill the resulting gap the air from the valley blows up the

valley. This wind is known as the valley

breeze. During the night the slopes get

cooled and the dense air descends into the

valley as the mountain wind. The cool air,

of the high plateaus and ice fields draining into the valley is called katabatic wind.

Another type of warm wind occurs on the

leeward side of the mountain ranges. The

moisture in these winds, while crossing

the mountain ranges condenses and

precipitates. When it descends down the

leeward side of the slope the dry air gets

warmed up by adiabatic process. This dry

air may melt the snow in a short time.

Anemometer: It is an instrument

used to measure the velocity and

direction of wind.

Wind Vane: It is used to indicate the

direction of the wind.

Monsoon Winds:

They are like land and sea breezes on

a large scale. They are periodic seasonal

winds that are characterized by a seasonal

reversal of winds. They blow from land to

sea in winter and sea to land in summer.

They prevail in the regions of the Indian

sub-continent, South East Asia and

Northern Australia. The term ‘monsoon’,

meaning season, is derived from the Arabic

word Mausim. The South-west monsoon

brings heavy to moderate rain to the Indian

landmass from June to September. In

winter, the monsoon receives its direction

so that winds blow out of the continent as

the North-east monsoon towards the Bay

of Bengal and Indian Ocean.

Local Winds:

These winds blow with some special

characteristics over a small area and last

for a short period. All these winds are

mostly seasonal and given local names.

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Geography

Name Location Characteristics

Loo Northern Indian Plains Hot and dry, Dust storm

It can be fatal.

Period: May to June

Chinook

means Snow

eater

Wind ward and

leeward side of Rocky

mountains

Warm and moist wind.

Gives rain and snow to windward side of

Rocky mountains.

Melts snow in the leeward side of Rockies.

Foehn Alps of Europe Similar to Chinook in character

Berg Off the South African

plateau

Similar to Chinook in character

Santa Ana Southern California Hot dry descending winds. They may even

cause fires in the dry areas.Mistral Shores of north-west

Mediterranean in

France

Cold dry winds

Bora Shores of north-west

Mediterranean in Italy

Cold dry winds

Leveche Spain Furious warm wind

Sirocco Northern Africa,

Southern Sicily

Hot and dry wind originating in the Sahara

desert and blows through the Mediterranean

sea to reach Sicily. Rainfall brought by these

winds are usually brown in color (due to

desert sand and dust in air) It is called Blood

Rain.

Nor’westers

(In Bengal

it is called

kalbaisaki)

Bengal and Assam Violent thunder storms during April to June,

before the onset of South-West monsoon. It is

the rain from these winds that sustains the

tea plants even in hot season.

Brick Fielder Australia Warm Wind

Harmattan Central Africa Warm Wind

Purga Russia Cold Wind

Norte Gulf of Mexico Cold Wind

Pampero Argentina Cold Wind

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Geography

Variable Winds:They are known as Cyclones in the

Indian Ocean, Hurricanes in the Atlantic,

Typhoons in the Western Pacific and South China Sea, and Willy-willies in the

Western Australia.

The variable winds have no definite location or direction. These winds are

getting fluctuated by means of its direction and speed. Cyclones and anti-cyclones

are included in this category. They affect

limited areas for a few days only.

Cyclone: Tropical cyclones are violent storms

that originate over oceans in tropical

areas and move over to the coastal areas

bringing about large scale destruction

caused by violent winds, very heavy rainfall

and storm surges. This is one of the most

devastating natural calamities.

Favourable Conditions:Tropical cyclones originate and

intensify over warm tropical oceans. The

conditions favourable for the formation

and intensification of tropical storms are: 1. Large sea surface with temperature

higher than 27°C;

2. Presence of the Coriolis force;

3. Small variations in the vertical wind

speed;

4. A pre-existing weak low- pressure

area or low-level-cyclonic

circulation;

5. Upper divergence above the sea level

system.

List of Tropical Cyclones that affected India

S.I No Year Name Affected State Named Country

1. 17th Oct 1999 Orissa,

Super Cyclone

- -

2. 2008 Nisha Tamil Nadu -

3. 2008 Laila Andra Pradesh -

4. 29th Dec, 2011 Thane - -

5. 2012 Nilam Andra Pradesh &

Tamil Nadu

-

6. 2013 Lehar & Helan Andra Pradesh

7. 2013 Phailin Odisha -

8. 2013 Madi Tamil Nadu -

9. 12 Oct, 2014 Hudhud Odish & Andra

Pradesh

Oman (It is Hoope

Bird which is called

Hudhud in Arabic)

10. Oct 2014 Nilofar - Gujarat - Pakistan

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Geography

The energy that intensifies the storm comes from the condensation process

in the towering cumulonimbus clouds,

surrounding the centre of the storm. With

continuous supply of moisture from the

sea, the storm is further strengthened.

On reaching the land the moisture supply

is cut off and the storm dissipates. The

place where a tropical cyclone crosses the

coast is called the landfall of the cyclone.

The cyclones, which cross 200N latitude

generally, recurve and they are more

destructive.

A mature tropical cyclone is characterized

by the strong spirally circulating wind

around the centre, called the eye. The

diameter of the circulating system can

vary between 150 and 250 km.

Eye of the Cyclone

The eye is a region of calm with subsiding

air. Around the eye is the eye wall, where

there is a strong spiralling ascent of air to

greater height reaching the tropopause.

The wind reaches maximum velocity in

this region, reaching as high as 250 km

per hour. Torrential rain occurs here.

From the eye wall rain bands may radiate

and trains of cumulus and cumulonimbus

clouds may drift into the outer region.

The diameter of the storm over the Bay

of Bengal, Arabian Sea and Indian Ocean

is between 600 - 1200 km. The system

moves slowly about 300 - 500 km per day.

The cyclone creates storm surges and they

inundate the coastal low lands. The storm

peters out on the land.

Temperate Cyclone:

Formed in Temperate areas

Formed in both land and ocean

areas.

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Geography

Formed due to frontal development.

Anti-Cyclone: The anticyclones are the

centres of the high pressure systems from

which the wind movement takes place

outward. These winds are associated with

clear weather and no rainfall. The anti-

cyclones move clock wise in the northern

hemisphere and anti-clock wise in the

southern hemisphere. They are mostly

formed over the land so they are dry.

HUMIDITY, CONDENSATION

AND PRECIPITATION

Water vapour present in the air is known

as humidity. It is expressed quantitatively

in different ways.

Absolute Humidity: The actual

amount of the water vapour present in

the atmosphere is known as the absolute

humidity. It is the weight of water vapour

per unit volume of air and is expressed in

terms of grams per cubic metre. The ability

of the air to hold water vapour depends

entirely on its temperature. The absolute

humidity differs from place to place on the

surface of the earth.

Relative Humidity: The percentage

of moisture present in the atmosphere

as compared to its full capacity at a

given temperature is known as the

relative humidity. With the change of

air temperature,the capacity to retain

moisture increases or decreases and the

relative humidity is also affected. It is

greater over the oceans and least over the

continents.

The air containing moisture to its full

capacity at a given temperature is said to

be saturated. It means that the air at the

given temperature is incapable of holding

any additional amount of moisture at that

stage. The temperature at which saturation

occurs in a given sample of air is known as

dew point.

Evaporation And Condensation:

The amount of water vapour in the

atmosphere is added or withdrawn

due to evaporation and condensation

respectively.

Evaporation is a process by which water

is transformed from liquid to gaseous state.

Heat is the main cause for evaporation.

The temperature at which the water

starts evaporating is referred to as the

latent heat of vapourisation. Increase

in temperature increases water absorption

and retention capacity of the given parcel

of air. Similarly, if the moisture content

is low, air has a potentiality of absorbing

and retaining moisture. Movement of

air replaces the saturated layer with the

unsaturated layer. Hence, the greater

the movement of air, the greater is the

evaporation.

The transformation of water vapour into

water is called condensation. Condensation

is caused by the loss of heat. When moist

air is cooled, it may reach a level when

its capacity to hold water vapour ceases.

Then, the excess water vapour condenses

into liquid form. If it directly condenses

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Geography

into solid form, it is known as sublimation.

In free air, condensation results from

cooling around very small particles termed

as hygroscopic condensation nuclei.

Particles of dust, smoke and salt from

the ocean are particularly good nuclei

because they absorb water. Condensation

also takes place when the moist air comes

in contact with some colder object and it

may also take place when the temperature

is close to the dew point. Condensation,

therefore, depends upon the amount of

cooling and the relative humidity of the

air. Condensation is influenced by the volume of air, temperature, pressure and

humidity. Condensation takes place:

(i) when the temperature of the air

is reduced to dew point with its

volume remaining constant;

(ii) when both the volume and the

temperature are reduced;

(iii) when moisture is added to the air

through evaporation. However,

the most favourable condition for

condensation is the decrease in air

temperature.

After condensation the water vapour

or the moisture in the atmosphere takes

one of the following forms - dew, frost, fog

and clouds. Forms of condensation can be

classified on the basis of temperature and location. Condensation takes place when

the dew point is lower than the freezing

point as well as higher than the freezing

point.

Dew: When the moisture is deposited

in the form of water droplets on cooler

surfaces of solid objects (rather than

nuclei in air above the surface) such as

stones, grass blades and plant leaves, it

is known as dew. The ideal conditions

for its formation are clear sky, calm air,

high relative humidity, and cold and long

nights. For the formation of dew, it is

necessary that the dew point is above the

freezing point.

Frost: Frost forms on cold surfaces

when condensation takes place below

freezing point (00C), i.e. the dew point is

at or below the freezing point. The excess

moisture is deposited in the form of minute

ice crystals instead of water droplets. The

ideal conditions for the formation of white

frost are the same as those for the formation

of dew, except that the air temperature

must be at or below the freezing point.

Fog and Mist: When the temperature

of an air mass containing a large quantity

of water vapour falls all of a sudden,

condensation takes place within itself on

fine dust particles. So, the fog is a cloud with its base at or very near to the ground.

Because of the fog and mist, the visibility

becomes poor to zero. In urban and

industrial centres smoke provides plenty of

nuclei which help the formation of fog and

mist. Such a condition when fog is mixed

with smoke, is described as smog. The

only difference between the mist and fog is

that mist contains more moisture than the

fog. In mist each nuceli contains a thicker

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Geography

layer of moisture. Mists are frequent over

mountains as the rising warm air up the

slopes meets a cold surface. Fogs are drier

than mist and they are prevalent where

warm currents of air come in contact with

cold currents. Fogs are mini clouds in

which condensation takes place around

nuclei provided by the dust, smoke, and

the salt particles.

Cloud: A cloud can be defined as a mass of small water droplets or ice

crystals formed by the condensation of

water vapour in the atmosphere. Clouds

are formed by very minute suspended

water particles present in the atmosphere.

According to the shape and altitude, the

clouds are classified as Cirrus, Stratus, Cumulus and Nimbus.

Cirrus clouds are high clouds because

they are formed above 5,000 metres above

sea level. They are naturally dry, consists

of ice crystals and never bring rainfall.

These clouds are long, fibrous, and curved, with no tufts or curls at the ends. Stratus

clouds are low clouds because they are

formed within 2,000 metres above the sea

level. They have uniform base and look like

a dark gray sheet. They may cause snow

and drizzle.

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Geography

Conventional Rainfall

Sun

lake

Solar radiation

heats water

Cumulo-nimbus clouds

are formed. Water droplets

accumulate and fall as rain

due to gravity

Air cools and condenses

with height, forming clouds

----------------------------------Dew point

Warmer airrises

Relief or Orographic Rainfall

Cumulus clouds are often described

as “puffy” or “cotton-like” in appearance

which are medium clouds. Cumulus

clouds may appear alone, in lines or in

clusters. These clouds are associated with

rainfall, lightning and thunder. They are

otherwise called as thunder clouds. They

extend up to 12,000 metres high above

the sea level.

Nimbus clouds are vertical clouds.

They are thick dark or gray or black clouds.

They cause continuous rainfall so they are

known as storm or rain clouds.

Rainfall:

Rainfall may be defined as the water drops that fall from the clouds to the

earth. The mechanism of rainfall begins

from evaporation then it continues as

condensation at considerable heights.

Later on, the clouds are formed which

may cause rainfall. The rainfall types are

classified into three as : Convectional, Relief or Orographical and cyclonic.

Since the equatorial regions receive

vertical sunrays they become hot, so that

the hot air expands and rises vertically

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Geography

upwards. As the temperature reduces

gradually, the air gets cooled and forms

clouds. When the clouds reach the dew

point, they cause rainfall. This is known

as the convectional rainfall. This type of

rainfall is accompanied with thunder and

lightning. Usually, it occurs around 4O

clock, hence, it is called 4’O clock rainfall.

The winds that blow from the sea contain

a lot of moisture. When the moisture laden

winds from sea climbs the hills across the

paths, the winds become cool causing

heavy rainfall on the windward side. This

is called as orographic rainfall. Then these

winds descend on the lee ward side of the

mountains and cause low to no rainfall

The warm air from the hot area is further

heated and moves upward. Hence, a low

pressure area is developed and attracts

air from the adjacent high pressure areas.

Due to Earth’s rotation, the wind gets

deflected and a circular motion of wind develops. The air rises upward in the form

of a funnel. The rising air gets cooled and

condensation takes place. This brings

heavy rainfall in the low pressure centres.

This is called as cyclonic rainfall. Example

during October, November and December,

the Northeast Monsoon season period,

there are a number of cyclones caused

along the coast of Tamil Nadu, Andhra

Pradesh and Orissa.

INDIAN CLIMATE

India has ‘Monsoon’ type of climate.

The word monsoon has been derived from

the Arabic word ‘mausim’ which means

seasonal reversal of the winds during the

course of the year. This implies a rhythmic

change in the direction of winds and in the

distribution of temperature and rainfall

with the change of season.

Factors Determining the Climate

of India:

India’s climate is controlled by a number

of factors.

1. Latitude: The mainland of India

extends roughly from 8oN to 37oN

latitude and the Tropic of Cancer

(23½oN) passes through the middle

of the country. Areas lying in the

north of Tropic of Cancer are in

sub-tropical and temperate zone

while those lying in the south of this

line fall in the tropical zone. There

is a gradual fall in temperature as

we move from south to north. The

tropical zone is nearer to the equator

and experiences high temperature

throughout the year.

2. The Himalayan Mountains :

The Himalayan mountains along

with its extensions in the north-west

and north-east act as a very effective

climate divide. It saves the Indian

subcontinent from the cold and chilly

winds originating near the Arctic

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Geography

Circle and blowing across central

and eastern Asia. The Himalayan

wall also traps the monsoon winds

from the Bay of Bengal and Arabian

Sea and cause widespread rainfall

in the sub-continent.

3. Distribution of Land and Water:

India is flanked by the Indian Ocean on three sides in the south and

girdled by a high and continuous

mountain wall in the north.

4. Distance from Sea: As mentioned

above, landmasses heat up and cool

down more quickly than water. As

such coastal areas enjoy equable

climate while areas located in the

interior i.e.,far away from the sea

experience extremes of climate.

5. Altitude: There is a gradual fall of

temperature with increasing altitude

at an average rate of 10C for 165

metres (or 0.650C per 100 metres).

Consequently places located in

mountains are cooler than places

located in plains. For example, Agra

and Darjiling are located on the

same latitude, but temperature of

January in Agra is 160C whereas it

is only 40C in Darjiling.

6. Relief: India has great

physiographic variations including

lofty mountains, vast plains and

extensive plateaus. These aspects

of relief have a great bearing on

temperature, air pressure, direction

and speed of wind and amount

and distribution of rainfall. The

windward sides of Western Ghats

and Assam receive high rainfall

during June-September whereas

the southern plateau remains dry

due to its leeward situation along

the Western Ghats.

a) Winter Season: Indian weather in

the winter season is generally influenced by the presence of high atmospheric

pressure in Central and West Asia. This

causes the flow of surface winds from the north to the Indian sub-continent. These

winds form a dry continental air-mass.

This air mass comes in contact with the

Indian trade winds.

b) Summer Season

i. With the onset of summer season,

the sun shifts towards the north

and there is a complete reversal

of pressure conditions and wind

circulation both in the lower and the

upper layers of the atmosphere.

ii. With the northwards shift of the

ITCZ, the westerly jet stream

withdraws from the Indian plain.

This low pressure ITCZ, attracts

winds from different directions.

The maritime tropical air (MT) from

southern hemisphere rushes to this

low pressure zone after crossing the

equator between 400 and 600 east

longitudes. This is known as the

south-west monsoon.

iii. The Retreat of the Monsoon.

The south-west monsoon starts

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Geography

retreating by 1st September from

the western strip of Rajasthan and,

by 15th September, it retreats from

most parts of Punjab, Haryana,

Rajasthan and Gujarat. It retreats

from most parts of India by mid-

October, except the southern

peninsula. The retreating monsoon

picks up moisture from the Bay of

Bengal and establishes itself over

Tamilnadu coast in the month

of December and causes rainfall

there.

El-Nino and the Indian Monsoon

El-Nino is a narrow warm current

which appears off the coast of Peru in

December. In Spanish, it means The

Child Christ because it appears around

Christmas. It is a temporary replacement

of the cold Peruvian or Humbolt current

which normally flows along the coast. It appears once in every three to seven years

and is responsible for wide spread floods and droughts in the tropical regions of

the world. Sometimes it becomes more

intense and increases the surface water

temperatures of the sea by 100C. This

warming of tropical Pacific water affects the global pattern of pressure and wind

system including the monsoon winds in

the Indian Ocean. The El Nino phenomena,

which influence the Indian monsoon, reveals that when the surface temperature

goes up in the southern Pacific Ocean, India receives deficient rainfall.

El Nino has a great impact on the

Indian monsoon and is used in India for

forecasting long range monsoon rainfall.

Meteorologists believe that the severe

drought of 1987 was caused by El Nino. In

1990-91, there was a wild El-Nino event

and the onset of southwest monsoon was

delayed over most parts of the country

ranging from five to twelve days.

La Nina

After El Nino, weather conditions return

to normal. However, sometimes trade

winds become so strong that they cause

abnormal accumulation of cold water in

the central and eastern Pacific region. This event is called La Nina, which in effect

is the complete opposition of El Nino. A

La Nino also marks an active hurricane

season. But In India, the presence of La

Nina portends exceptionally good news. It

is the harbinger of heavy monsoon showers

in India.

Southern Oscillation (S.O.) is the

name ascribed to the curious phenomenon

of sea saw pattern of meteorological

changes observed between the Pacific and the Indian Oceans. It has been noticed

that whenever the surface level pressure

is high over the Indian Ocean, there is low

pressure over the Pacific Ocean and vice-versa. When the winter pressure is high

over the Pacific Ocean and low over the Indian Ocean, the south-west monsoons

in India tend to be stronger. In the reverse

case, the monsoons are most likely to be

weaker.

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Geography

Some Famous Local Storms of Hot

Weather Season

i. Mango Shower, Towards the end

of summer, there are pre-mensoon

showers which are a common

phenomena in Kerala and coastal

areas of Karnataka. Locally, they

are known as mango showers since

they help in the early ripening of

mangoes.

ii. Blossom Shower. With this shower

coffee flowers blossom in Kerala and nearby areas.

iii. Nor Westers. These are dreaded

evening thunderstorms in Bengal

and Assam. Their notorious nature

can be understood from the local

nomenclature of ‘Kalbaisakhi’, a

calamity of the month of Baisakh.

These showers are useful for tea,

jute and rice cultivation. In Assam,

these storms are known as “Bardoli

Chheerha”.

iv. Loo. Hot, dry and oppressing winds

blowing in the Northern plains

from Punjab to Bihar with higher

intensity between Delhi and Patna.

••••••

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Geography

OCEAN RELIEF

Continents and ocean basins are

the first order relief features of the earth. The ocean floors are not flat or uniform. The floor of the oceans is as irregular as the surface of the continents.

Ocean basins, platforms, trenches, submarine ridges.

1.1 Configuration of Ocean Floor1. Continental Shelf2. Continental Slope3. Continental Rise

OCEANOGRAPHY

4. Trench (or) Ocean Deep

5. Deep Sea Plain

Continental Shelf1. This is the coastal part of the ocean,

the slope of the bottom is very gentle, with a gradient of 1-20.

2. Generally this part extends upto a depth of about 100 fathoms. (180mt)

3. They occupy 7.6% of the oceans area.

4. Generally the shelf is broader along the coast lines of submergence and narrower along the coastlines of emergence.

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Geography

5. It is a relatively narrow platform where the mountain ranges occur close to the coast of continents. Ex. Andes Mountain - Eastern

Pacific OceanExcept India - The breadth of the

shelf is lesser along the Bay of Bengal than along the Arabian Sea Coast.

6. Banks, Reefs are generally found here.

7. The shallowness of the shelf enables the sunlight to penetrate through the water. This fosters growth of minute plants and microorganisms which provide food for the other marine life.

8. This is one of the reasons why the world’s Chief fishing grounds are found in the shallow waters.

Ex. North Sea, Grand Bank of New foundland Island.

9. Many of them are dissected by Valleys and troughs. (Submarine Canyons)

Continental Slope1. The steep slope which descends from

the edge of the continental shelf to the deep ocean bed is known as the continental slope.

2. It has a gradient ranging between

20 and 50. It spreads from 200m to 2500m deep.

3. It constitutes about 8.5% of the ocean floor.

4. It is cut through by submarine Canyons. Some of these appear to be continuations of river valleys while the others seem to be a result of faulting.

Continental Rise:1. It may be up to several hundred km

in width and has very low gradients of less than 10.

2. At the foot of the continental slope is found an area slightly rising due to the accumulation of the debris transported over the continental slope.

3. Large accumulations of the deposited rock material are found here and usually this part is rich in minerals found in the sedimentary rocks.

4. Some of the oil deposits of the oceanic areas occur in this zone

Trench:1. Considerable depth on the deep sea

plain of the ocean floor. 2. They occur either in association

with island arcs or along the coasts bounded by high mountain ranges.

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Geography

The ocean deep is often associated with the subduction zone at the margins of two tectonic plates. (Plate Tectonics)Ex. The deepest is the (Challenger Deep) Mariana Trench in the west Pacific,

about 10,800m below sea level. Aleutian Trench - near Aleutian Island-North Pacific Ocean Kuril Trench - near Kuril Island - West Pacific Mindanoa Deep - Phillippines Trench (Galathea deep) – West Pacific

Ocean.

Romanchee deep - Atlantic ocean in equator (break in the continuity of mid Atlantic Ridges)

Tonga Trench - South Pacific Ocean - 2nd deepest Trench in the World.

Kermadec trench - South Pacific Ocean Puerto Rico Trench - Deepest trench in Atlantic Ocean. (Milwaukee Deep) Java Trench - Indian Ocean

The Abyssal plain or the Deep or

the Deep sea plain1. This is the deepest and the most

extensive part of the ocean floor.2. It is occupied by raised ridges or

submarine mountains and by the very deep trenches.

3. A number of volcanic mountains are found.

4. Ridge - Ex. Mid-Atlantic Ridge - central part of the A.O. 900 E ridge - Indian Ocean.

5. Volcanic Islands - some parts of the ridges may reach the surface of the oceans and may thus form islands. Ex. Hawaiian Island.

6. Sea mount - Volcanic peaks which remain under water

7. Guyots: Some of these peaks are much higher and reach close to the surface. The top of such peaks eroded through the wave action to make them almost flat topped.

Submarine ReliefsOceans:

In all there are five oceans on the earth. They are:

1. The Pacific Ocean 2. The Atlantic Ocean 3. The Indian Ocean

4. The Arctic Ocean

5. The Antarctic Ocean

First three oceans are more important and the relief of their floor is briefly discussed here.

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Geography

1. THE PACIFIC OCEAN:Size and Shape: This is the largest ocean of the world. It has an area of 16, 57, 23, 740 sq km which is about one-third the total area of the world.

Floor: The Pacific is the deepest of all the oceans. Continental shelf is not much developed in this ocean. Only 7% of this ocean is less than 1,000 metre deep. The major portion of the basin has an average depth of about 7,300 metres. The Northern Pacific is the deepest part, (5,000 - 6,000 metres). There are several

trenches or deeps in this part. Some well known trenches or deeps in this part. Some wellknown trenches are Aleutain, Kurile, Japan and Bonin trench. They are 7,000 - 6,000 metres deep. There are several seamounts, guyots, and islands in the central part. Of the south-west portion of the Pacific, there is trinental shelf and sub-marine trenches. Here, Mariana trench is 11,033 metre deep. This is the deepest part of the earth discovered so far. Mindanao trench, which is 10,500 metre deep, is also located here.

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Geography

Major Relief Features of the Pacific Ocean

The south-east Pacific has broad submarine ridges and plateaus. The most important are the Albatross Plateau (3,000 - 4,000 metres deep) and South-Eastern Pacific Plateau (2,000 - 4,000 metres deep). Atacama trench off the coast of Atacama is 8,000 metres deep. Near the Tonga Island, there is Tonga trench which is 9,000 metres deep.

Islands: This is vast ocean has more than 20,000 big and small islands. Bigger islands are located near the continental coasts and are made up of rocks similar to those of the continents. Towards the east are the

Aleutian, British Columbia and the Chile Islands. The west coast of this

ocean is dotted with Kurile, Japan, Philippines and New Zealand. Islands located in the mid-ocean are coral and volcanic in origin.

2. THE ATLANTIC OCEAN:Size and Shape: The total area of the Atlantic Ocean is 8,29,63,800 sq km. It is thus half the size of the Pacific Ocean and accounts for nearly 1/6th part of the earth’s surface area. It extends from Greenland in the north to the Antarctic continent in

the south. It resembles the shape of letter ‘S’. On the west, it is bounded by North and South America and on the east by Europe and Africa.

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In the south, it is open and may be considered to extend upto the continent of Antarctica.

Floor: The most striking feature of the Atlantic Ocean is the presence of the mid-Atlantic Ridge. It extends from Iceland in the north to Bouvet Island in the south paralleling the ‘S’ shape of the ocean itself. It becomes quite broad at 550 N and is known as Telegraph Plateau. Romanche deep near the equator divides this ridge into two parts. The northern part is

known as Dolphin Range while the southern part is called Challenger Ridge.

Although it is a submarine ridge, yet some of its peaks project out of water in the form of islands. Azores, Pico and Cape Verde islands are its main examples. St. Paul near the equator has very sharp peak. Ascension Tristan -da- Cunha, St. Helena and Gough and Bauvet islands in the south Atlantic are of volcanic origin. Bermuda is a coral island.

Islands: The Atlantic Ocean lacks in islands. In the North Atlantic, there are Newfoundland, British Isles and West Indies. In south Atlantic only Falkland islands are worth mentioning. Some smaller islands appear on the Mid-Atlantic Ridge which have already been discussed.

Troughs and Trenches: The Atlantic Ocean also lacks in troughs and trenches. According to Murray, there are 19 deeps with depth exceeding 5,500 metres. Only two are more than 7,000 metres deep. North Cayman Romanche and South Sandwich are the two trenches in the Atlantic Ocean.

3. THE INDIAN OCEAN:Floor: Continental shelf in this ocean is much less as compared to Atlantic Ocean. Its average depth is 4,000 metres and its 60% part is 4,000 to 6,000 metres deep sea plain. The floor of the Indian Ocean has fewer irregularities in comparison to the other two oceans. Linear deeps are

almost absent. The only exception is the Sunda Trench, which lies south of the island of Java and runs parallel to it.

Ridges: There are a number of broad submarine ridges on the floor of the Indian Ocean. The most important submarine ridge runs from Kannyakumari continuously southward to Antarctica. It is situated in the middle and divides the ocean into two basins on either side. It is

called the Lakshdweep - Chagos Ridge in the north, the ChagosSt. Paul Ridge in the middle and the Amsterdam St. Paul Plateau in the south, where it widens out considerably.

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The central ridge is bifurcated into many small ridges which reach the coasts of Africa and India. Two minor and parallel ridges run north-westward. These are known as the Socotra - Chagos Ridge and the Seychelles Ridge.

Another ridge, known as the South Madagascar Ridge, runs southward from the Madagascar Island. It widens in the south, where it is called the Prince Edward Crozet Ridge. In the Bay of Bengal, another ridge called the Andaman Nicobar extends from the mouth of the Ayeyarwadi (Irrawaddy) to the Nicobar Islands. Beyond this towards the south, a very important ridge runs along the 900 E longitude and is known as Ninety East Ridge. The Carlsberg Ridge has been discovered by recent surveys and it divides the Arabian Sea into two parts.

Islands: Most of the islands near the coast of the Indian Ocean are detached parts of the continental blocks. The Andaman and Nicobar, Sri Lanka, Madagascar and Zanzibar are important examples of this group. The Lakshdweep and Maldives Islands are coral islands. The Mauritius and Reunion islands to the east of Madagascar are of volcanic origin. The eastern section of the Indian Ocean is almost devoid of islands.

OCEAN RESOURCESOceans cover about 71% of the earth’s

surface area and are great source of a large variety of resources. Oceans contain huge amounts of minerals, food resources and energy resources.

Mineral Oil: Mineral oil is the most important mineral obtained from the sea bed so far, as the value is concerned. Most of the oil resources are found on the continental shelves but borings for deeper oil wells have been done in the recent past. At present, more than 75 countries are extracting mineral oil from the sea bed. The main producers are the Middle East countries, U.S.A., Britian, Norway, the Netherlands, Ireland, Ukraine, Indonesia, Ghana, Australia and New Zealand. In India, Mumbai High, Bassein, Aliabet product oil and Krishna-Godawari off-shore basin produces natural gas.

Oceans and Food Resources: Two

most important items of food obtained from the oceans are fisheries and aquaculture. Most of the fish varities are found on the continental shelves upto the depth of 100 fathoms because this zone provides suitable conditions for the growth of different varieties of fishes. The major fishing grounds of the world are found in

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the temperate zone of the northern hemisphere.

This zone contains the following four major fishing grounds:

1. The North-West Pacific Fishing Ground

2. The North-West Atlantic Fishing Ground

3. The North-East Atlantic Fishing Ground

4. The North-East Pacific Fishing Ground

Potential of Tidal energy in India

1. Gulf of Khambhat (7000 Mw)2. Gulf of Kutch (1000 Mw)3. Sunderbans (100 Mw)

In addition to fish, other sea organisms such as mussels, lobsters, molluscs, and squard crastacanas oyster are also used as important items of food.

Aqua cultural products include finfish, shellfish, oyester, mussel, milkfish, seaweeds etc. About two thirds of the total aquacultural products are accounted for by finfish.

Seaweeds are found in almost all the seas although a large amount of seaweeds grow in tropical and temperate zones. Seaweeds are used as food in China, Taiwan and Japan. In Western Europe, seaweeds were used as fodder for animals and fertilizer in earlier days; but now they are used for a large variety of purposes such as in medicines, milk industry, confectionery and textile industry.

Oceans and Power Resources:Tidal Energy: Tides occur in the oceans twice a day and they can yield a lot of energy. A tidal range of over 3 metres is sufficient to produce electricity. Two areas in the world offer great potential for generating tidal electricity. They are (i) Bay of Fundy in Canada and (ii) Severn Estuary in Britain. India also holds vast potential for harnessing tidal energy. The most suitable conditions are provided by the gulf of Khambhat and Gulf of Kachchh. Here the maximum and average tidal ranges are 8-11 and 5-23 metres respectively. Sunderban also holds great potential. These three projects can produce 800-900 megawatt electricity. National Power Corporation has set up a 900 MW tidal energy power plant in Gulf of Kuchchh, Gujarat.

Wave Energy: Waves of sea water have enormous energy which can be harnessed for the ben efit of mankind. Japan, Norway and U.S.A have done pioneer work in this regard. In India, a plant at Vizhinjam, 26 km away from Thiruvananthapuram has been installed to harness the wave energy.

Sea Thermal Power (OTEC): If the minimum difference of temperature of the surface water and that at the

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depths varying from 1000 to 3000 metres is 200C, then sea thermal energy can be produced. Such a situation prevails in the tropical zone where the surface water temperature is 250 - 300C and the

water temperature at greater depths in about 50C. Floating generators to harness this energy have been set up in Cuba, near Miami coast and Hawaii Island in the U.S.A. and in Japan.

Geothermal Energy: This energy is obtained from the volcanic eruptions occurring on the sea floor. Successful attempts have been made in New Zealand and the U.S.A. to harness this energy.

There are several hundred hot springs in India.

They can be used to generate electricity.

Two experimental projects have been set up in India to harness geothermal energy. One them is located in Parvati

valley near Manikaran in Himachal Pradesh

The other project is located in the Puga valley of Ladakh region in Jammu & Kashmir.

TEMPERATURE OF OCEANSThe Major source of temperature of the oceanic water is the sun.

Factors affecting distribution of

Temperature

1. Latitude2. Unequal distribution of Land water3. Prevailing winds4. Ocean Currents5. Submarine ridges6. Shape and size of the Sea.

Horizontal Distribution:1. The surface temperature of ocean

decreases gradually from the equator to the poles.

2. The oceans in the N.H. (19.40C)

record relatively high average temperature than in the S.H. (16.10 C)

because of unequal distribution of land & ocean water.

3. The highest temperature is not recorded at the equator.

4. Highest temperature recorded in tropical region. (23 to 270C)

5. The average annual temperature of all the oceans is 17.20C.

6. The average annual temperature of the pacific ocean is slightly higher than the Atlantic (16.90C) and

Indian Ocean (170 C)

7. But enclosed seas of the Indian Ocean is recorded highest

temperature. Arabian Sea have high temperature than Bay of Bengal.

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Vertical Distribution1. Temperature of ocean water changes

with increasing depth.

2. The temperature remains almost equal to that on the surface up to a depth of about 100mts.

3. The rate of fall of temperature with increasing depth varies with latitude also. This rate is higher at the equator than at the poles.

Temperature - Vertical

DistributionFirst Layer

Top layer of warm oceanic water and it is about 500m thick with temperature ranging between 200

and 250 C.

This layer with in the tropics is present throughout the year but in mid latitudes it develops only during summer.

Summer Layer: (Thermocline Layer)

(500-1000m Thick)

It is characterised by rapid decrease in temperature with increasing depth.

Third Layer:

It is very cold and extends up to the deep ocean floor.

Arctic and Antarctic:

The surface water temperatures are close to O0C and so the temperature change with depth is very slight. Here only one layer of cold water exists.

SALINITY OF OCEANSThe salinity of water is the total weight

of dissolved salts to the weight of water. It is expressed as the number of parts of salt dissolved in 1000 parts of water.

Isohalines: The lines join the places of equal salinity at the sea surface.

Factors affecting distribution of

Salinity

1. Rate of evaporation2. Precipitation3. Discharge of rivers4. Atmospheric Pressure5. Wind direction6. Circulation of Oceanic Water

Salt in Sea Water

1. Sodium Chloride - 78%2. Magnesium Chloride3. Magnesium Sulphate4. Calcium Sulphate5. Potasium Sulphate

Distribution

1. The average salinity of oceans is 35 parts per thousand. (35%)

2. It varies from place to place.3. The greatest salinity is not found on

the Equator. The temperature here are high but the rate of evaporation is not high because of high humidity and frequent rain.

4. Tropical: (Trade wind belt) Maximum salinity is found in the tropical areas where the sun’s heat is greatest and the rainfall is lowest.

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5. Polar Regions: (Minimum salinity) the effects of low temperature and water melted from glaciers reduce the salinity.

Arctic Ocean :

20 parts per thousandBaltic sea :

Baltic Sea - Salinity is very low. Only 11%. Because of slow rate of evaporation and many streams and rivers which add their fresh water. It, therefore, freezes rapidly.Arabian Sea :

38% - There is higher rate of evaporation due to relatively less humid conditions and low influx of freshwater as compared to Bay of Bengal.Bay of Bengal :

Only 30%, in Ganga delta only 20%.Red Sea :

37- 41% (no river flows)Dead Sea :

240% - evaporation high - very little rainfall. few stream flows. Lake van :

Turkey - 330% - highest.Great Salt Lake : 220%.

Vertical Distribution of Salinity:1. Surface Layer:

A shallow surface layer of uniformly high salinity. (35 to 36.5%)2. Halocline:

1. A zone of rapid decrease in salinity.2. It corresponds with the

thermocline.3. Below it, differences in salinity are

very small.

Polar Areas:

1. In high latitude areas the salinity tends to increase with increasing

depth.

2. In mid latitude areas, the salinity tends to increase with increasing

depth upto 400 mt and then tends to decrease again.

3. In equatorial regions, the salinity has slight increase with increasing depth initially but then starts decreasing again.

THE TIDESThe alternate rise and fall in the waters of the ocean that occurs twice in about 24hrs are known as tides.

Tides:Tides are caused by the gravitational pull of the moon and to some extent by the pull of the sun.The water of the earth nearest to the moon will be pulled by the moon’s gravitational force.The moon is directly over one side and its attraction causes the water to pile up towards the same side causing an ordinary high tide at that place.

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The water level at right angle side of earth is lowered and it is low tide (ebb tide) at those points.

At the same time there is a piling up of water on the other side of the earth towards opposite. (According to the

Universal Law of Gravitation, the side of the earth facing the moon has a force of attraction at point A and the side which is farthest from the moon has a centrifugal force, almost equal to the force of attraction at point B)These tides travel in a great wave around the earth following the moon except where the land stops them. They hit the sea coast at intervals of about 12hrs and 26 minutes.Two high tides and two low tides occur in every 24 hrs and 52 minutes.This is due to the fact that the moon is revolving around the earth in the same direction as the earth’s rotation.

In the open oceans such as the Atlantic, tide flow and ebb regularly twice a day. In the enclosed seas such as Mediterranean Sea and the Baltic, the range is very small, but in the Bay of Fundy the tide may rise 15 to 20mts.

Spring Tides:

Twice during the lunar month, namely, just after the New moon and the full moon the earth, moon and the sun are in the same straight line and the gravitational

effects of the moon and the sun are combined to produce tides which are higher than usual.

The high tide is very high and the low tide is very low. When the moon is perigee the spring tides are still higher (1st January) (when the earth is nearest the sun)Neap Tides:

At the time of the first and last quarter of the moon, the sun and the moon are at right angles to each other in relation to earth.

The gravitational pull of the sun opposes that of the moon and difference between high and low tide levels is the least. The high tide is lower and the low tide is higher. These are called Neap Tides.

Tidal Current: When a gulf is connected with the open sea by a narrow channel, water flows into the gulf at the time of high tide and comes out of the gulf at low tide. This movement of water, inward and outward, is known as tidal current. The heights of these tides may be ten metres or more.

Tidal Bore: When a tide enters the narrow and shallow estuary of a river, the front of the tidal wave appears to be vertical owing to the filling up of the water of the river against the tidal wave and the friction of the river bed. This steep-nosed tide crest looks like a vertical wall of water rushing upstream and is known as a tidal bore. Hooghly river in West Bengal often experiences tidal bores.

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OCEAN CURRENTSThe ocean current is the general

movement of a mass of water in a fairly defined direction over great distances.

Causes of oceanic currentsi. Mainly caused by the difference in

density of sea water due to variations in temperature and salinity.

ii. Prevailing winds.iii. The position of the landmasses and

the shape and depth of the ocean basins.

iv. Earth Rotation (Coriolis force)v. Seasonal Changes

Two types of oceanic currents

1. Warm currents: flow from the low latitudes to high latitudes.

2. Cold currents: flow from high latitudes towards equator ward.

Oceanic Currents of North Atlantic

Ocean:1. North Equatorial Current: It flows

from the coast of Africa in the east to the West Indies in the west parallel to the equator under the influence of the trade winds.

2. Antilles Current: The South Equatorial current bifurcates into two branches near Cape-de-Sao Roque (Brazil). Its northern branch reinforces the North Equatorial Current. Part of the combined current enters the Caribbean Sea and the Gulf of Mexico, while the remainder passes along the eastern side of the West Indies as the Antilles Current.

3. Florida Current: The branch

entering the Gulf of Mexico is reinforced by a great bulk of warm

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ocean water driven by the trade winds and by the water brought by the Mississippi river. As a result, the water level in the Gulf rises as compared to that of the Atlantic Ocean. This difference in water level is compensated for by the current flowing out through the Strait of Florida and this branch is joined by the Antilles current. From the Cape of Florida, the combined current moves along the south-eastern coast of the United States and is known as the Florida Current upto the Cape-Hatteras.

4. Gulf Stream: Beyond the Cape Hatteras upto the Grand Banks off Newfoundland, it is known as the Gulf Stream. The Gulf Stream receives plenty of warm water from the Gulf of Mexico and carries it to cold areas.

5. North Atlantic Drift: From the Grand Banks, the Gulf Stream flows eastward across the Atlantic under the influence of the prevailing westerly winds. Here it is known as North Atlantic Drift. Its speed is quite large in the open ocean.

6. Norwegian Current: The North Atlantic Drift is divided into two branches when it reaches the

European Coast. The northern branch reaches the British Isles from where it flows along the coast of Norway as the Norwegian current and enters the Arctic Ocean.

7. Canaries Current: The second

branch of the North Atlantic Drift takes a southerly turn and flows between Spain and Azores as the cold Canaries Current. This current finally joins the North Equatorial Current Completing the circuit in the North Atlantic.

8. East Greenland Current: This

current flows from north to south along the eastern coast of Greenland.

9. Labrador Current: This current starts from the Baffin Bay and Davis Strait and flows along the coast of Labrador. It brings a large number of icebergs from the Baffin Bay. The East Greenland Current joins it at the southern tip of Greenland. The joint current moves further southwards and joins with the Gulf Stream. The confluences of warm Gulf Stream and cold Labrador current produces thick fog near Newfoundland. Sargasso Sea: It is the calm sea

lying within the circuit of North Atlantic Current, Gulf Stream, North Atlantic Drift and Canaries Currents. It is full of seaweeds known as sargassum in the Portuguese language. Hence, it is known as Sargasso Sea.

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Oceanic Currents of South Atlantic

Ocean:1. South Equatorial Current: It lies

in the south of equator and flows almost parallel to it from east to west.

2. Brazil Current: The South Atlantic current splits into two branches near Cape-de-Sao Roque (Brazil). The northern branch joins the North Equatorial current, whereas the southern branch turns southward and flows along the South American coast as the Brazil Current.

3. South Atlantic Current: The Brazil current swings eastward at about latitude 350 S to join the West-wind Drift flowing from west to east.

4. Benguela Current: Near the Cape of Good Hope, a branch of the South Atlantic current flows northward along the west coast of South Afirca. It is a cold current and is known as the Benguela Current. It finally joins the south Equatorial Current, thus completing the circuit.

5. Falkland Current: Another cold current, known as the Falkland Current, flows along the south-eastern coast of South America from south to north. This brings huge icebergs from the Antarctic region and creates thick fog when it joins the warm water.

Oceanic Currents of Indian

Ocean:The characteristics of the currents of

the Indian Ocean are quite different from those of Pacific and Atlantic Oceans. This is due to the fact that it is just half an ocean and is completely land-locked in the north. The currents of the northern Indian Ocean change their direction due to seasonal change in the direction of the monsoons. The current affected by monsoons is known as the ‘Monsoon Drift’.

The southern part of the Indian Ocean extends right upto the Antarctic Coast and is not influenced by seasonal changes. The general pattern of circulation is simple and is anti-clockwise like that of the other southern oceans.

North Indian Ocean:1. Winter Conditions: In winter, the

north equatorial current is under the influence of north-east monsoon and blows from east to west. This is known as North-East Monsoon Drift. It starts from the Strait of Malacca and flows along the coast of Bay of Bengal. After crossing Sri Lanka, it flows along the coast of Arabian Sea and turns southwards. From there it travels from west to east as counter Equatorial Current and completes the anticlockwise circulation.

2. Summer Season: During summer, a strong current flows from west to

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east which completely obliterates the North Equatorial Current during this season. It is due to the effects of the strong south-west monsoon and the absence of the North-East Trades. There is no counter Equatorial Current at this time of the year. Thus, the circulation of water in the northern part of the ocean is clockwise during this season.

South Indian Ocean:The circulation of currents of South

Indian Ocean is similar to that of South Pacific and South Atlantic Oceans. Following scheme explains these currents:

1. South Equatorial Current: Like other oceans, Indian Ocean has

south equatorial current flowing parallel to the equator from east to west.

2. Mozambique Current: The South Equatorial Current divides itself into two branches on reaching

Madagascar. One of them flows through the Mozambique channel between Mozambique and Madagascar coasts. This is a warm current and is known as warm Mozambique Current.

3. Madagascar Current: The other

branch of the South Equatorial Current flows along the east coast of Madagascar and is known as Madagascar Current.

4. Agulhas Current: In the south of Madagascar Island, the Mozambique and the Madagascar currents join with each other. After the confluence of these two streams, it is known as the Agulhas Current. It still continues to be a warm current till it merges with the west wind drift.

5. The West Wind Drift: The west

wind drift is a cold current which flows from west to east and reach the southern tip of the west coast of Australia.

6. West Australian Current: On

reaching Australia, the west wind drift is divided into two branches. One of the branches moves northwards along the west coast of Australia and is known as West Australian Current. It ultimately joins the south equatorial current and completes the counter clockwise circuit in the South Indian Ocean.

Oceanic Currents of Pacific

Ocean:From the point of view of study of ocean

currents, the Pacific Ocean is divided into North Pacific and South Pacific.

North Pacific Ocean:1. North Equatorial Current: It

flows across the ocean from east to west. Starting from the west coast of Central America, it reaches the Philippine Islands in the Western Pacific Ocean.

2. Kuroshio Current: On reaching

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the Philippine Islands, the north equatorial current turns towards the north along the coasts of Taiwan and Japan and is known as Kuroshio Current.

3. North Pacific Current: After reaching the south-east coast of Japan, the Kuroshio current comes under the influence of the prevailing westerlies and flows from west to east. Here it is known as North Pacific Current.

4. Californian Current: The North

Pacific Current is bifurcated into the two currents on reaching the west coast of North America. Its one branch goes towards the north

and the other is turned towards the south. The southward current flows along the coast of California as a cool current. It is known as Californian Current.

5. British Columbia or Alaska

Current: The northern branch of the North Pacific Current flows anticlockwise along the coast of British Columbia and Alaska and is

Cold Current

Warm CurrentWest Wind Draft

South Pacific Current

South Equatorial Current

Counter Equatorial Current

North Equatorial Current Cal

abria

C.

North Pacific Current

Oya

shio

C.

Alaska Current

Equator

Per

u C

urr

ent

Currents of Pacific Ocean:

Kur

oshi

o C.

Eas

t Aust

rali

an

Okhots

k C

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known as the Alaska Current. The water of this current is relatively warm as compared to that of the sea in this zone.

6. Oya Shio Cold Current: It starts

from Bering Strait and flows southwards as a cold current along the east coast of Kamchatka peninsula.

7. Okhotsk Current: Another cold current in the North Pacific is the Okhotsk Current which flows past Sakhalin to merge with the OyaShio Current off Hokkaido. The OyaShio finally merges with and sinks beneath the warmer water of the Kuroshio.

Due to the meeting of Kuroshio warm current from the equator and the OyaShio cold current from the polar region meets at the east coastal region of Japan.

South Pacific Ocean:1. South Equatorial Current: It is a

warm current which flows almost parallel to the equator from the coast of Central America towards the east coast of Australia.

2. East Australian Current: The south equatorial current turns towards the south on reaching the coast of New Guinea under the influence of Coriolis force. It is a warm current which flows along the east coast of Australia. Hence, it is known as East Australian Warm Current.

3. South Pacific Current: The East Australian current turns towards to east under the influence of the westerlies and is known as South Pacific Current.

4. Peru Current: On reaching the

south-western coast of South America, the South Pacific current turns northward and flows along the Peru Coast as the Peru Current. It is a cold current which finally feeds the South Equatorial Current, completing the great circuit. Counter Equatorial Current:

Between the North and the South Equatorial Currents, a current flows from west to east which is known as the Counter Equatorial Current. The North and the South Equatorial Currents cause accumulation of water in the western parts which

disturbs the surface level. This difference in the level makes the Counter Equatorial current flow eastward.

CORAL REEFS AND ATOLLS:1. Coral reefs and atolls are formed

due to accumulation of skeletons of lime secreting organisms known as coral polyps.

2. Coral Polyps thrive in the tropical oceans. They live, at a place, in groups in the form of colony and

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form calcareous shells around them.

3. Coral reefs are formed due to formation of one shell upon another shell along submarine platforms at suitable depth. So it is always found either upto sealevel or below it.

4. Coral reefs are more diverse than the tropical rain forests because it has about 10 lakhs species. This is why these are called as rainforests of the oceans.

Conditions for the Growth of coral

polyps:1. Tropical oceans and seas – require

high mean annual temperature.2. Clean sediment free water but not

fresh water3. Ocean currents and waves are

favourable because they bring food supply for the polyps. (so grows only in open seas oceans)

4. It do not live in deeper waters because of lack of sunlight and oxygen.

Types of coral Reefs:1. Fringing Reef:

Coral reefs developed along the continental margins or along the Islands. Ex. Lakshadweep Island

2. Barrier Reef:

Largest coral reefs off the coastal platforms but parallel to them.

Largest, most extensive, highest &

widest reef.

3. Great Barrier Reef:

Australia has the largest of all the barrier reefs of the world.

Atoll:

A ring of narrow growing corals of horseshoe shape and crowned with

palm trees

It is generally found around an Island.

Coral bleaching:It refers to loss of algae from the corals

resulting into the white colour which is indicative of death of corals.

Causes of coral bleaching:1. Globalwarming has been reported as

the major factor of coral bleaching.2. Phenomenal increase is coral

bleaching- 1983, 1987, 1998 – associated with strong ELNINO.

3. Coral diseases, black band diseases, coral plague

Coral Bleaching aspergillosis and white band diseases cause coral death.

4. Siltation of sea, water pollution of sea water

5. Collection of rare coral species.6. Destructive fishing practices7. Mining of coralrocks.

Coral Reefs in IndiaLakshadweep, Andman Nicobar Island,

small patches of coral reefs in Gulf of

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Kutch& Gulf of Mannar.Ex. Coral bleaching Andaman & Nicobar

Island – This bleaching is related to rise in temperature from the normal temperature in the Andaman Sea in 1997-98.

National Institute of Oceanography

- GoaEx. The coral reefs of Lakshadweep

have suffered great damage due to bacterial diseases and warmer sea temperature.

Ex. The corals in the Gulf of Kutch have been bleached due to siltation.

Arabian sea have a coral origin and are surrounded by fringing reefs (over the volcanic peak)

Car Nicobar – coral Island chowra – Nicobar Island

1. Catastrophic bleaching – adversely affecting 95% of corals Bahrain, Maldives, Srilanka, Singapore, Tanzania.

2. Severe bleaching – 50 – 70% - Kenya, Seychelles, Japan, Thailand, Vietnam

3. Moderate bleaching – 20 – 50% - coral monality with quick recovery.

4. No bleaching.

Deserts

Sahara desert - AfricaGobi desert - China – coldKalahari - BotswanaTaklamakan - ChinaSonoran (Arizona) - USA, MexicoMojave - USA, MexicoNamib - NamibiaKarakum - Turmenistan- coldAtacama - peru – chileOnly cold desert in India - Ladakh.

Marine Resources

India – Western coast areas more than east – less fish catch due to tropical climate

Food Resources

Fish – Grand Bank near New found land, Dogger Bank in North sea

Crabs, shrimps, zoo plankton

Plant Resources

Phyto Planktons, sea grass etc. (primary producer) or autotrophs.

Mineral ResourcesCommon salt – Gujarat, M.H, Tamilnadu.

Gujarat alone produces 50% of total salt.

Tropical regions with high temperature are the ideal areas for the production of salt from sea.

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Chlorine, bromine, iodine, uranium

Fresh water – Reverse osmosis technique is used to obtain potable water from oceans.

Petroleum of Natural gas – Bombay High in India. Bassein – South of Mumbai High, Gulf of Khambat.

Energy Resources

Waves and tidal energy

Kutch region of Gujarat – tidal energy plant gulf of Khambat.

Wave energy – vizhinjam near Tiruvanathapuram in Kerala Coast. (150KW)

OTEC – Ocean thermal energy conversion.

Tuticorin – Tamil Nadu.

Potential of tidal energy

1. Gulf of Khambhat (7000MW)2. Gulf of Kutch (1000MW)3. Sunderbans (100MW)

Important Terms:Bay : An open, curving indentation made

by the sea or a lake into a coastline.

Gulf : An inlet of the sea of large areal proportions more indented than a bay and generally more enclosed. Elongated steepsided and flat floored Valley.

Isthmus : A narrow tract of land separating two bodies of water and connecting two large bodies of land e.g. Isthmus of Panama.

Strait : A relatively narrow waterway linking two larger bodies of water e.g. Dover strait – links the North sea with the English Channel.

Peninsula : A narrow neck of land projecting into a body of water.

TNPSC FACTS

ENVIRONMENTAL LAWS

Air (Prevention and control of pollution) Act, 1981. It was amended in 1987.

Biological Diversity Act, 2002 National Biodiversity Authority (NBA) is a statutory autonomous body, headquartered in Chennai, under the Ministry of Environment and Forests, GOI established in 2003 to implement the provisions under the Act.

Environment Protection Act, 1986. Forest (conservation) Act, 1980.

••••••

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INTERNAL STRUCTURE OF

THE EARTH

The Universe was formed due to a cosmic

explosion approximately 10 to 20 billion

years ago. This is explained as “The Big

Bang Theory.” The land and water bodies

were not distributed as it is now. All the

continents were clustered together around

the South Pole. This super continent was

called Pangea, which means All Earth (in

Greek). The Pangea was surrounded by

a Mega Ocean called Panthalassa which

means All Ocean (in Greek). The Pangea

was broken in to a number of plates called

the Lithosphere plates. These plates move

around very slowly from a few millimeters

to a centimeter a year.

By analyzing the seismograph of various

Earthquakes, scientists have discovered

that three main layers exist within

the earth. Isaac Newton was the first scientist to theorize about the structure of

the Earth. The layer which we live in is a

relatively very thin layer when compared

GEOMORPHOLOGY (LITHOSPHERE)

to the other two layers. The interior of

the earth is divided into three layers

depending on the Chemical composition

and characteristics. They are:

1. Crust 2. Mantle 3. Core

Crust:

The uppermost layer of the earth’s crust

is called the crust.

Continental Crust Oceanic Crust

SIAL (Silica +

Aluminium)

SIMA (Silica +

Magnesium)

Mantle:

Mantle lies between the crust and the

core. It comprises about 83% of the earth’s

volume. It is made up of plates that move

and create continental drift. Beyond 900

Kms, this layer is completely homogenous.

Upper mantle is known as Asthenosphere.

It extends up to 700 Kms. Lower mantle is

semi solid and is plastic in nature. The

average density of the mantle is 8.

Core:

The innermost layer of the earth is called

core or the barysphere. It is otherwise

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Geography

known as NIFE (Nickel + Ferrous). This

layer is responsible for earth’s magnetic

field. There are two main divisions: the

outer core and the inner core. The particles

present here resemble a liquid. It may be

in a solid state due to excessive pressure

of the surrounding. The density of the

core is 12.

Forces Of Earth Movement:

The crust of the earth is not stable.

Several areas of the present land masses

were once beneath the sea. Continuous

changes are taking place on the surface of

the earth. Once upon a time, the Himalayas

were the Tethys Sea. A few of the changes

are gradual and slow, some of them are

sudden. These changes are brought about

by two forces:

1. Endogenic or internal forces

2. Exogenic or external forces

Endogenic forces:

It originates from within the crust. It

gives rise to deformation and irregularities

on the crust of the earth. The earth

movements which bring about large

amount of change on the crust is called

Endogenetic Force. These movements are

of two types:

Diastrophism/ Slow Movement

Sudden Movement

Slow Movements or Diastrophism:

It is the general term applied to slow

bending, folding, warping and fracturing.

This can be classified into two types:Orogenic/ Vertical Movement

Epirogenic/ Horizontal Movement

Epirogenic Movement:

It is also called the Continental

Movement. The vertical movement either

leads to uplift or subsidence of the earth’s

crust, along lines of weakness called

FAULTS. Displacement of the earth’s

crust takes place along the fault line.

When displacement takes place along two

adjoining fault lines, a portion between

them may get uplifted to form Block

mountains or plateaus, or subside to form

a basin of Rift valley.

Orogenic Movement:

It is also called Mountain building

Movements. Horizontal movements of the

earth’s crust are responsible for folding

and displacement of layer of rocks. Simple

folding consists of alternating upfolds

called Anticlines and downfolds called

Synclines. Such simple folds rarely occur.

More often, folds get displaced to such

an extent that the layer of the rock gets

displaced to a greater distance. They

are responsible for the formation of Fold

Mountains of the world.

Sudden Movements:

These movements bring sudden

changes on and below the crust. These

movements are destructive in nature. The

major destructions are happened due to

Earthquakes and Volcanic activities.

EARTHQUAKES AND

EARTHQUAKES IN INDIA

An earthquake is a sudden shaking

or trembling of a part of the earth’s

crust which results in tremors and

vibrations. An earthquake can be either

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Geography

a volcanic earthquake or a tectonic

earthquake. Volcanic earthquakes occur

along with a volcanic eruption and the

tectonic earthquakes are caused by their

deformation or displacement in rocks.

Focus is the point of origin of the

earthquake. It is also called Hypocenter.

Epicenter is the point above the focus

on the surface where the waves are first felt.

Measurements:Richter Scale: The strength of an

earthquake is known as its magnitude,

which is measured in Richter scale.

Magnitude is the amount of energy released

during the earthquake.

Marcauli Scale: The intensity of an

earthquake is measured using this device.

Intensity is the visible amount of damage

caused by the earthquake.

Types of Earthquake Waves:Basically earthquakes are divided into

two: Body waves and Surface waves

Body Waves: They are produced by the

release of energy at the focus and move

in all directions through the body of the

earth. They are of two types:

PRIMARY WAVES SECONDARY

WAVES

They are also

called P- Waves.

They are also

called S- Waves.

They’re the first to be recorded on

seismograph.

They’re recorded

after the P- Waves.

Particles vibrate

parallel to the

direction of

propagation of the

wave.

Particles vibrate

perpendicular to

the direction of

propagation of the

wave.

It travels at a

speed of 8Kmpsec.

It travels at a

speed of 5Kmpsec.

Surface Waves:

They’re also called L- Waves. They’re

the last to be recorded on the seismograph.

These waves are responsible for the wide

scale visible damage on the surface of the

earth. It travels at a speed of 4Kmp sec.

Causes for Earthquake:

There are four main causes for

Earthquakes, namely:

1. Volcanicity

2. Folding and Faulting

3. Anthropogenic effect

4. Plate tectonic theory

Volcanicity: Each volcanic activity is

followed by an earthquake. The explosive

violent gases try to escape upwards

pushing the crustal rocks from below

with great force and thus it causes severe

earthquakes.

Folding and Faulting: The horizontal

and vertical movements caused by

endogeneic forces result in the formation

of faults and folds which in turn causes

isostatic disequilibrium in the rocks which

ultimately causes earthquakes.

Anthropogenic Effect: It means Man-

made causes. Pumping ground water and

oil, deep underground mining, construction

of dams and reservoirs, nuclear explosion

causes earthquakes.

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Geography

Plate Tectonic theory: (This topic will

be dealt in detail in the next chapter.)

Earthquakes in India:

Earthquke in India can be dealt with in

three regions

1. Himalayan region

2. Plain region

3. Plateau region

Himalayan Region:

It is the zone of maximum intensity of

earth quake, because this zone is situated

in subducted zone of the Asiatic plate

and Indian plate where the process of

mountain building is still in progress. The

Asiatic plate is moving southwards and

the Indian plate is moving Northwards.

The northern region of the Indian plate

is subducted below the Asiatic plate.

Thus, folding and faultings are formed

which are responsible for earthquakes.

Ex: Uttarkashi earthquake, 1999, Samohi

earthquake, 1999

Plain Region: It is a zone of

comparatively moderate earthquakes.

Ex: Bihar earthquake, 1934, Assam

earthquake, 1956, Barbanga earthquake,

1988

Peninsular India: It is a zone of

minimum intensity.

On the basis of the magnitude of damage

risk, India is divided into 5 damage risk

zones:

Zone 5 Zone 4 Zone 3 Zone 2 Zone 1

Very high

damage risk

zone

High damage

risk zone

Moderate

damage risk

zone

Low damage

risk zone

Very low damage

risk zone

Jammu &

Kashmir,

Western

Himachal

Pradesh,

Uttarkhand,

Western &

North Bihar,

North east

India, Kutch

areas of

Gujarat

Part of Jammu

& Kashmir,

Himachal

Pradesh,

Northern

Punjab, Eastern

Haryana,

Delhi, Western

Uttar Pradesh,

Northern Bihar

South and

South eastern

Rajasthan,

Most parts

of Madhya

Pradesh,

Maharashtra,

Jharkand,

Karnataka,

North and

Northwest

Orissa

Southern

Punjab and

Haryana,

Southern

plains

of Uttar

Pradesh,

Eastern

Rajasthan,

Coastal

districts of

Orissa and

Tamil Nadu

Plain areas of

Uttar Pradesh

Plains of Bihar

and West Bengal

Delta areas of

Godavari,

Coastal plains of

Maharashtra and

Kerala

Desert areas of

Rajasthan, Most

areas of Gujarat

except Kutch

regions.

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Geography

Lithosphere = Crust+ Upper part of

upper mantle

Oceanic Plate Continental Plate

When ocean

occupies large

portion of the

plate.

When continent

occupies large

portion of the

plate.

Thickness: 5-100

Kms

Thickness: 5-200

Kms

Ex: Pacific Plate Ex: Eurasian plate

The theory of plate tectonics proposes

that the earth’s lithosphere is divided

PLATE TECTONICS

In 1967, three scientists - McKenzie,

Parker, Morgan - independently collected

the available ideas and came out with

another concept termed Plate Tectonics.

A tectonic plate, also called a lithospheric

plate, is a massive irregularly-shaped slab

of solid rock, generally composed of both

continental and oceanic lithosphere. Plates

move horizontally over the asthenosphere

as rigid units. The lithosphere includes

the crust and the upper part of the upper

mantle.

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Geography

into seven major plates and several minor

plates. The seven major plates are:

1. Antartic plate

2. Pacific plate3. North American plate

4. South American plate

5. India- Australia- New Zealand plate

6. African plate

7. Eurasian plate

These plates have been constantly

moving over the globe throughout the

history of the earth. It is not the continent

that moves as believed earlier. Continents

are part of a plate and what moves is the

plate. Moreover, it may be noted that all

the plates, without exception, have moved

in the geological past, and shall continue

to move in the future period as well. There

are three types of plate boundaries:

Divergent Boundaries:

It is where new crust is generated as

the plates pull away from each other. The

sites where the plates move away from

each other are called spreading sites.

Most of the active volcanoes are found

along the mid oceanic ridges. The depth of

‘focus’ ranges between 25 km to 35 km. So

moderate earthquakes are caused in these

plate boundaries. The best-known example

of divergent boundaries is the Mid-Atlantic

Ridge. At this, the American Plate(s) is/are

separated from the Eurasian and African

Plates.

Convergent Boundaries:

Where the crust is destroyed as one

plate dived under another. The location

where sinking of a plate occurs is called

subduction zone. There are three ways in

which convergence can occur.

(i) Between an oceanic and continental

plate

(ii) Between two oceanic plates and

(iii) Between two continental plates

Earth quakes of high magnitude and

deep focus are caused along the convergent

plate boundaries.

These boundaries are associated with

explosive type of volcanic eruptions. ex.

Volcanoes of circum pacific belt

Transform Boundaries:

It is where the crust is neither

produced nor destroyed as the plates slide

horizontally past each other. Transform

faults are the planes of separation generally

perpendicular to the mid-oceanic ridges.

As the eruptions do not take all along the

entire crust at the same time, there is a

differential movement of a portion of the

plate away from the axis of the earth. Also,

the rotation of the earth has its effect on the

separated blocks of the plate portions.

Ex : Earthquakes of California.

Force for the Plate Movement:

When the theory of continental drift was

proposed, most scientists believed that

the earth was a solid, motionless body.

However, concepts of sea floor spreading

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Geography

and the unified theory of plate tectonics have emphasized that both the surface of

the earth and the interior are not static

and motionless but are dynamic. The

fact that the plates move is now a well-

accepted fact. The mobile rock beneath

the rigid plates is believed to be moving

in a circular manner. The heated material

rises to the surface, spreads and begins

to cool, and then sinks back into deeper

depths. This cycle is repeated over and to

generate what scientists call a convection

cell or convective flow. Heat within the earth comes from two main sources:

radioactive decay and residual heat.

The slow movement of hot, softened

mantle that lies below the rigid plates

is the driving force behind the plate

movement.

The molten material is formed in the

mantle. It is called Magma in the mantle.

When the magma reaches the surface of

the earth, it is called Lava.

VOLCANOES

A volcano is a vent or an opening on

the earth’s crust, through which hot

molten materials erupt from the interior.

The eruption of materials from the interior

of the earth’s crust may occur with huge

explosions or quiet in nature.

Types of Volcanoes:

There are three types of volcanoes. This

classification is based on the frequency of eruption. They are:

1. Active Volcanoes:

It erupts frequently. Most of the active

volcanoes are formed along the mid-

oceanic ridges. Mauna loa in Hawaii

island is the largest active volcano of the

world. The Barren island is the only active

volcano in India.

2. Dormant Volcano:

They are called sleeping volcanoes.

These volcanoes are active in the past,

stopped ejecting lava now, but it can erupt

at any time in the future.

Ex: Vesuvius of Italy, Mauna Kea of

Hawaii.

3. Extinct Volcanoes:

They are also called dead volcanoes.

They erupted in the past but they did not

do so recently and in future it is expected

there will not be any eruptions.

Ex: Mt. Kilimanjaro of Africa, Narcondam

Island of Andaman Island Tiruvannamalai

hills of Tamil Nadu, Panaka hills of Andhra

Pradesh.

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Geography

Volcanic Eruption Gases :

The principal components of volcanic

gases are water vapur (H2O), Carbon

dioxide (CO2), Sulfur either as sulphur

dioxide (So2) or Hydrogen sulphide (H

2S),

Nitrogen, Argon, Helium, Neon, Methane,

Carbon monoxide, and Hydrogen etc.

The abundance of gases varies

considerably from volcano to volcano.

Watervapour is consistently the most

common volcanic gas, normally comprising

more than 60% of total emissions. CO2

typically accounts for 10 to 40% of

emissions.

Volcanic bomb

Steam

Volcanic

block

Pumice

lava

ash

Materials

ejected

Volcanic Eruption - Materials

TSUNAMIS

High magnitude earthquakes, massive

undersea landslides and volcanic eruptions

that cause the sea-floor to move abruptly resulting in sudden displacement of ocean

water in the form of high vertical waves are

called tsunamis (harbor waves) or seismic

sea waves. Normally, the seismic waves

cause only one instantaneous vertical

wave; but, after the initial disturbance,

a series of afterwaves are created in

the water that oscillate between high

crest and low trough in order to restore

the water level.

The speed of wave in the ocean

depends upon the depth of water. It is

more in the shallow water than in the

ocean deep.

As a result of this, the impact of

tsunami is less over the ocean and more

near the coast where they cause large-

scale devastations. Therefore, a ship at

sea is not much affected by tsunami and

it is difficult to detect a tsunami in the deeper parts of sea. It is so because over

deep water the tsunami has very long

wave-length and limited wave-height.

Thus, a tsunami wave raises the ship

only a metre or two and each rise and fall

takes several minutes. As opposed to this,

when a tsunami enters shallow water, its

wave-length gets reduced and the period

remains unchanged, which increases

the wave height. Sometimes, this height

can be up to 15m or more, which causes

large-scale destructions along the shores.

Thus, these are also called Shallow Water

Waves.

In deep water, very long wave length

and limited wave height.

Tsunamis are frequently observed along

the Pacific ring of fire, particularly along

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Geography

the coast of Alaska, Japan, Philippines,

and other islands of Southeast Asia,

Indonesia, Malaysia, Myanmar, SriLanka,

and India etc. After reaching the coast, the

tsunami waves release enormous energy

stored in them and water flows turbulently onto the land destroying port-cities and

towns, structures, buildings and other

settlements. Since the coastal areas are

densely populated the world and these are

also centres of intense human activity, the

loss of life and property is likely to be much

higher by a tsunami as compared to other

natural hazards in the coastal areas.

Unlike other natural hazards, the

mitigation of hazards created by tsunami

is difficult, mainly because of the fact that losses are on a much larger scale. It is

beyond the capacity of individual state or

government to mitigate the damage.

Hence, combined efforts at the

international levels are the possible ways

of dealing with these disasters as has been

in the case of the tsunami that occurred

on 26th December 2004 in which more

than 300,000 people lost their lives. India

has volunteered to join the International

Tsunami Warning System after the

December 2004 tsunami disaster.

Petrology is science of rocks. A

petrologist studies rocks in all their

aspects viz., mineral composition,

texture, structure, origin, occurrence,

alteration and relationship with other

rocks. As there is a close relation between

rocks and landforms, rocks and soils, a

geographer requires basic knowledge of

rocks

ROCKS

Rocks are formed by many biological,

physical, chemical activities of the earth.

The earth’s crust is composed of rocks.

A rock is an aggregate of one or more

minerals. Rock may be hard or soft and in

varied colours. Rocks do not have definite composition of mineral constituents.

Feldspar and quartz are the most

common minerals found in rocks.

There are many different kinds of rocks

which are grouped under three families on

the basis of their mode of formation. They

are: (i) Igneous Rocks (ii) Sedimentary

Rocks (iii) Metamorphic Rocks.

Igneous RocksIgneous rocks form out of magma and

lava from the interior of the earth, they

are known as primary rocks. The igneous

rocks (Ignis – in Latin means ‘Fire’) are

formed when magma cools and solidifies. When magma in its upward movement

cools and turns into solid form it is called

igneous rock. The process of cooling and

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Geography

solidification can happen in the earth’s crust or on the surface of the earth.

Igneous rocks are classified based on texture. Texture depends upon size and

arrangement of grains or other physical

conditions of the materials. If molten

material is cooled slowly at great depths,

mineral grains may be very large. Sudden

cooling (at the surface) results in small and

smooth grains. Intermediate conditions of

cooling would result in intermediate sizes

of grains making up igneous rocks.

Granite, gabbro, diorite, pegmatite,

basalt, volcanic breccia and tuff

are some of the examples of igneous

rocks.

Sedimentary RocksThe word ‘sedimentary’ is derived from

the Latin word sedimentum, which means

settling. Rocks (igneous, sedimentary and

metamorphic) of the earth’s surface are

exposed to denudational agents, and are

broken up into various sizes of fragments.

Such fragments are transported by different

exogenous agencies and deposited. These

deposits through compaction turn into

rocks. This process is called lithification. In many sedimentary rocks, the layers of

deposits retain their characteristics even

after lithification.

Types of Sedimentary Rocks:Depending upon the mode of formation,

sedimentary rocks are classified into three major groups:

a. Mechanically formed - sandstone,

conglomerate, clay, shale, loess etc.

b. Organically formed - geyserite,

chalk, limestone, coal, coral etc.

c. Chemically formed - gypsum,

rocksalt, nitrate, halite, potash etc.

Metamorphic RocksThe word metamorphic means ‘change

of form’. These rocks form under the action

of pressure, volume and temperature (PVT)

changes. Metamorphism occurs when

rocks are forced down to lower levels by

tectonic processes or when molten magma

rising through the crust comes in contact

with the crustal rocks or the underlying

rocks are subjected to great amounts of

pressure by overlying rocks.

Metamorphism is a process by which

already consolidated rocks undergo

recrystallization and reorganization of

materials within original rocks.

Igneous Rocks Metamorposed

into

Metamorphic

Rocks

1. Granite Gneiss

2. Basalt Schist

Sedimentary

Rocks

Metamorposed

into

Metamorphic

Rocks

1. Clay Slate

2. Limestone Marble

3. Sandstone Quartzite

4. Shale Schist

5. Coal Graphite

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Geography

INTRODUCTION:

India Location

India lies in the northern and eastern

hemispheres of the globe between

8O4’N and 37O6’N - Latitudes and

68O7’E and 97O25’E longitudes.

Tropic of Cancer (23½o) passes

through middle of the country

dividing India into two equal halves.

There is a maritime boundary of

6100 kms along the mainland.

Total coastlines including Is lands is

- 7516 kms

IndIa Water resources -

IndIa physIcal &

rIvers In IndIa

Durand Line - India - Afghanistan and

Pakistan - Afghanistan International

boundary.

McMohanline - India China Eastern

boundary (1140 km) (1913-14 - Shimla

convention)

Radcliff line- India - Pakistan - at the

time of partition (1947)

Size and Shape:

Total Geographical area - 32, 87, 263

sq.km. Which is 2.4% of the total

area of world land.

India is the seventh largest country

in the world.

In population size India occupies

second place in the world after

China.

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Geography

Important facts :

1. Panchsheel policy - 1954 - between

India & China

2. Tashkant

Agreement - 1966 - between

India & Pakistan

3. Shimla Agreement - 1972 - between

India and

Pakistan

Physiography

Study the present relief features of the

earth’s surface.

Land →Mountains - 10.7%

Hilly area - 18.6% (300 -

2135m)

Plateau - 27.7%

Plain - 43%

Himalayas

Himalayas are a series of parallel

ranges. The ranges have very steep

gradient towards the south but they

present a much gentler slope towards

the north.

Great Himalayas (Himadri or Inner

Himalayas)

This is the northernmost or the inner

most of all the Himalayan ranges.

It is mainly formed of the central

crystallines (granites & gneisses)

overlaid by Metamorphed

Sediments.

This mountain range has tallest

peaks of the world, most of which

remain under snow.

i. Mountain

Everest - 8850m above

sealevel.

- Nepal name -

Sagarmatha

- Tibet - Chomlungma

ii. Kanchenjunga, Makalu, Dhaulagiri,

Nanga parbat, Annapurna.

Note: Valley of Kashmir is located

between Himachal and Zaskar range

Passes :

Burzil Pass, Zojila in Jarkhand

Bara Lachala, Shipkila in Himachal

Pradesh

Thaga La, Niti, Lipul Lekh in

Uttarkhand

Nathu La, in Sikkim

Note: Valley of Kashmir is located

between Himachal and Zaskar range

Middle or Lesser Himalaya

(Himachal)

Ranges :

Pirpanjal, Dhaula Dhar, Mussoorie

Range (120 km) Nag Tiba, Mahabharat

Lekh (Southern Nepal)

Shiwalik Range :

(Outer Himalayas)

Outer most range of the Himalayas

It is formed of great thickness of

Mid-pleistocene sands, gravels

and conglomerates, which have

been brought by the rivers from

Himalayas.

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Geography

They are called Jammu Hills in Jammu

Dafla, Misi, Abor and Mishimi hills in Arunachal Pradesh, Dhang Range,

Dundwa Range in Uttarkhand.

In Siwaliks, the lakes were drained

away leaving behind plains called

‘duns’ in the west and duars’ in the

east Ex: Dehra Dun

Trans Himalays (Tibetan

Himalyas)

Zaskar, Ladakh, the Kailas and kara-

koram are the main ranges.

Karakoram range (or) Krishnagiri

range

K2 is the second highest peak in the

world and highest peak in the Indian

union (Godwin Austin)

Ladakh Plateau - Cold desert lies

to the northeast of the Karakoram

Range. Highest plateau (5000 mt) of

the Indian union Aksai Chin Plain is

here.

The general east west trend of the

Himalayas terminates suddenly at its

western and eastern extremities and the

ranges are sharply bend Southward and is

called syntaxical bend.

1. North Indian Plain:

The North Indian plain is also called

the Gangetic plain. The total area of

this plain is about 6,52,000 sq. km.

This plain is situated between the

Himalayan Mountains in the north

and the Peninsular plateau in the

south and is formed by the alluvium

brought down by the rivers.

The plain is very fertile and agriculture

is the main occupation of the people.

Many perennial rivers flow across the plain. Since the land is almost flat, it is very easy to construct irrigation

canals and have inland navigation.

It has excellent roads and railways,

which are helpful for the establishment

of many industries. 40% of the total

population of India lives here and it

is called “The heart of India”.

2. Peninsular Plateau:

It is the largest of India’s physical

divisions. It is the oldest and is

formed of hard rocks. The Narmada

rift valley divides the peninsular

plateau into two parts.

They are the Malwa plateau and the

Deccan plateau. The Malwa plateau

is bounded by the Aravalli hills in

the north-west and the Vindhya

Mountains in the south.

The total area of both these plateaus

is 7,05,000 sq. km. and the shape is

triangular. The Malwa plateau slopes

towards the Gangetic Plain.

The highest peak on the Aravallis

is Mt. Guru Shikhar. The Deccan

plateau is surrounded by the Satpura

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Geography

hills, the Mahadeo hills, the Maikala

range, the Amarkantak hills and the

Rajmahal hills in the north and the

Western Ghats in the west and the

Eastern Ghats in the east.

The Western Ghats are called

Sahyadris in Maharashtra and

Karnataka and further south they

are called Nilgiris in Kerala and

Annamalai range, Cardamom and

Palani hills in Tamilnadu.

Anaimudi in Annamalai range (2,695

mts.) is the highest peak in South

India. The Western Ghats and the

Eastern Ghats meet in the Nilgiri

hills.

The Peninsular plateau has economic

importance because of its rich mineral

resources and many rivers, which

have waterfalls. They help in the

generation of hydroelectric power.

The plateau is also suitable for the

cultivation of cotton and the dense

forests are the home of many wild

animals.

3. Coastal Plains and Islands:

Excluding the islands, the mainland

of India has 6,100 kms length of

coastline. It extends from Kachchh in

Gujarat in the west to the Gangetic

delta in the east.

The coast of India is divided into

western coast and eastern coastal

plains. The western coastal plain

lies between the Western Ghats

and the Arabian Sea and from the

Gulf of Kachchh in the north upto

Cape Comorin (Kanyakumari) in the

south, with a length of about 1,500

km. It is divided into Malabar coast,

Karnataka coast(Canara), Konkan

coast, Gujarat coast and Kachchh

and Kathiawad peninsulas.

The coast is straight and affected by

the South-West Monsoon winds over

a period of six months. So, there are

only a few good harbours Mumbai,

Marmagoa, Cochin, Mangalore,

Karwar, Nhava-Sheva and Kandla

are the important ports on the West

Coast.

The eastern coast extends from

Kanyakumari to the Gangetic delta

and between the Eastern Ghats and

the Bay of Bengal. It consists of the

deltas of rivers Mahanadi, Godavari,

Krishna and Kaveri. It is a broad and

flat land.

There are some salt water lakes or

lagoons. Chilka Lake of Orissa and

Pulicat Lake of Tamilnadu are the

best examples. The Eastern Coast is

divided into Coromandel coast in the

south and Utkal coast in the north.

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Geography

The coastal regions of India are noted

for agriculture, trade, industrial

centres, tourist centres, fishing and salt making. They provide important

hinterlands for the ports. These

coastal plains play a very important

role in the economic development of

India.

4. Islands of India:

There are 247 islands in India, out

of which there are 204 islands in the

Bay of Bengal and 43 islands in the

Arabian Sea.

There are a few coral islands in the

Gulf of Mannar also. The Andaman

and Nicobar Islands in the Bay of

Bengal consist of hard volcanic

rocks.

The middle Andaman and Great

Nicobar Islands are the largest islands

of India. Lakshadweep islands in the

Arabian Sea are formed by corals.

The southern - most point of India

is in the Greater Nicobar Island.

It is called Indira Point (formerly

it was called Pigmalion Point),now

submerged after 2004 Tsunami.

Majuli Island - Largest River Island in

the world is in Manipur.

WATER RESOURCES

Three-fourth of the earth is surface is

covered with water. But only a small

proportion of it accounts for fresh

water that can be put to use.

96.5% of the total volume of water

in the world is estimated to exist in

oceans.

Only 2.5% exist as fresh water. Nearly

76% of this fresh water is confined in ice sheets and glaciers in Antarctica,

Greenland and the mountainous

regions of the world.

A little less than 30% is stored as

ground water in the world’s aquifers.

India receives nearly 4% of the global

precipitation. India ranks 133 in the

world in terms of water availability

per person, per annum.

RIVERS OF INDIA

The Drainage System:

The drainage system is an integrated

system of tributaries and a trunk

stream which collect and funnel

surface water to the sea, lake or some

other body of water.

The total area that contributes water

to a single drainage system is known

as a drainage basin.

A geometric arrangement of streams

in a region, determined by slope,

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Geography

differing rock resistance to weathering

and erosion, climate, hydrologic

variability, and structural controls of

the landscape is known as a drainage

pattern.

Thus, drainage pattern refers to a

design which a river and its tributaries

form together, from its source to its

mouth.

India has the following drainage

patterns:

The Antecedent or Inconsequent

Drainage: The rivers that existed

before the upheaval of the Himalayas

and cut their courses southward by

making gorges in the mountains are

known as the antecedent rivers.

Consequent Rivers: The rivers which

follow the general direction of slope

are known as the consequent rivers.

Most of the rivers of peninsular India

are consequent rivers.

Subsequent Rivers: A tributary

stream that is eroded along an

underlying belt of non-resistant

rock after the main drainage

pattern (consequent river) has been

established is known as a subsequent

river. Due to the northward slope

of the Peninsula towards the Great

Plains, the rivers originating from the

Vindhyan and the Satpura ranges flow northward into the Ganga system.

The Chambal, Sind, Ken, Betwa, Tons

and Son meet the Yamuna and the

Ganga at right angles. They are the

subsequent drainage of the Ganga

drainage system.

Superimposed Epigenetic

(Discordant) or Superinduced

Drainage :It is formed when a stream

with a course originally established

on a cover of rock now removed by

erosion, so that the stream or drainage

system is independent of the newly

exposed rocks and structures.

Dendritic Drainage: A term used for

drainage which is branching thereby

giving the appearance of a tree. Most

of the rivers of the Indo-Gangetic

Plains are of dendritic type

Trellis Drainage: Trellis is a

rectangular pattern formed where

two sets of structural controls occurs

at right angles. In a trellis pattern,

the river forms a net like system and

the tributaries flow roughly parallel to each other.

Barbed Pattern: A pattern of drainage

in which the confluence of a tributary with the main river is characterized

by a discordant junction-as if the

tributary intends to flow upstream and not downstream.

Rectangular Drainage: The drainage

pattern marked by right-angled bends

and right-angled junctions between

tributaries and the main stream is

known as rectangular drainage.

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Geography

Radial Pattern: It is a pattern

characterised by outflowing rivers, away from a central point, analogous

with the spokes of a wheel. It tends to

develop on the flanks of a dome or a volcanic cone.

Annular Pattern: In this drainage

pattern, the subsequent streams

follow curving or arcuate courses

prior to joining the consequent

stream.

Parallel Drainage: The drainage

pattern in which the rivers flow almost parallel to each other is known

as parallel drainage.

Deranged Pattern: This is an

uncoordinated pattern of drainage

characteristic of a region recently

vacated by an ice-sheet.

Indian rivers are of two categories:

Northern rivers and Peninsular

rivers.

Northern rivers:

Indus:

It has 5 tributaries Chenab, Ravi, Beas,

Satluj and Jhelum. Chenab is the largest.

The Indus is one of the most important

drainage systems of the subcontinent of

India. It has a length of 2880 km, of which

709 km lies in India. The catchment area

of the Indus is about 1,165,000 sq km, out

of which about 321,284 sq km is in India.

Satluj is the only one that doesn’t origi-

nate in India.

Ravi, Beas, Satluj, Chenab and Yamuna

flow through Himachal Pradesh.Jhelum (Vitasta):

1. Srinagar is on banks of Jhelum. It

is the most important river of Kash-

mir.

2. Rises at Verinag

Chenab (Asikni):

1. Two headward tributaries: Chandra

and Bhaga

Ravi (Parushni or Irawati):

1. Source near Rohtang pass in Himach-

al Pradesh

Beas (Vipasa or Argikiya):

1. Source near Rohtang pass in Himach-

al Pradesh

2. Entirely within India.

Satluj (Satadru or Satudri):

1. Originates near Mansarovar.

Narmada Bachao Andolan:

Narmada Bachao Andolan is non-

government organisation (NGO).

It has mobilised tribal people,

farmers, environmentalist against

the Sardar Sarovar Dam built across

the Narmada river in Gujarat.

It is originally focussed on the

environmental issues related to

trees that would be submerged

under the dam water.

Now it has re-focussed the aim to

enable the poor citizens (displaced

people) to get full rehabilitation

facilities from the government.

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Geography

Multi – purpose river projects

and integrated water resources

management:

Sophisticated hydraulic structures

like dams built of stone rubble, res-

ervoirs or lakes, embankments and

canals for irrigation have been con-

structed from ancient times in India

to conserve and manage water.

Dams are a barrier across flowing water that obstructs, directs or re-

tards the flow, often creating a reser-voir, lake or impoundment.

Earlier dams were built to impound

rivers and rainwater for irrigation.

RIVER SYSTEMS IN INDIA

Types of Rivers

Antecedent- Himalayan Rivers

which existed before upheaval of

Himalayas. Eg. Indus, Ganga, Tista,

Brahmaputra etc

Consequent - Follows direction of

slope. Eg Peninsular Rivers

Subsequent - Carve out their own

path over a weak layer of rock. Meet

other rivers at right angles. Eg.

Central Highland Rivers.

Himalayan Rivers

1. Indus River System

Origin - Bokhar Chu glacier, Lake

Mansarovar, Tibet

Enters India through Ladakh

Upper tributaries - Zaskar, Shyok,

Hunza, Nubra, Shigar, Gasting and

Dras

Important tributaries -

Jhelum - Verinag, Pir Panjal

Range

Chenab - largest tributary , called

Chandrabhaga, originates near

Bara Lacha Pass

Ravi - Rohtang Pass , flows through Chamba Valley and Kullu

Hills

Beas - Beas Kund, Rohtang Pass,

meets Satluj at Harike Lake -

Indira Gandhi Canal

Satluj - Rakas Lake , Mansarovar

Range , passes through Shipki La

pass

2. Ganga River System

Origin - Gangotri glacier in

Uttarkashi

Starts as Bhagirathi , meets

Alaknanda at Devprayag

Left Bank tributaries

Ramganga - Gahrwal Hills

Sarda (Kali) - Milam Glacier, Nepal

- UK boundary

Gomati - Pilbit , UP [Pilbit Tiger

Reserve]

Ghagra - Mapchachungo glacier,

Tibet

Gandak - Nepal Himalayas

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Geography

Kosi - Gosainath peak, Tibet ,

forms Saptkosi after joining Arun

Right Bank tributaries

Yamuna - Yamnotri Glacier ,

Banderpunch peak , Garhwal

Chambal - Mhow, Malwa Plateau,

Gandhi Sagar dam , famous for

Chambal Ravines , meets Yamuna

Sind - tributary of Yamuna

Betwa - Vindhyanchal , joins

Yamuna

Ken - Yamuna

Son - Amarkantak Plateau (a

famous tributary is Rihand) ,

directly meets Ganga

Damodar - Chota Nagpur Plateau

(known for the Damodar Valley

Cooperation) (Like Narmada flows through a rift)

3. Mahananda river (Darjeeling

Hills) is other major tributary

In WB it bifurcates - a tributary

‘Bhagirati and Hugli’ fall southwards in

WB itself. The mainstream ‘Padma’ goes

into Bangladesh and meets Brahmaputra

to form river Meghna. The delta region of

this river are the Sunderbans.

4. Brahmaputra River System

Origin - Chemayungdung glacier,

Kailash Range, East of Mansarovar

Lake

Enters India by making a U turn at

Namcha Barwa peak in Arunachal

Pradesh

Called Dihang in AP - joined by

Dibang and Lohit

Rivers through AP - Kameng, Suban-

siri, Siang, Tirap and Lohit

Sankosh and Manas river (comes

from Bhutan to Assam) is also a trib-

utary

Barak River - rises in Manipur Hills

North Tributaries - Subansiri, Ka-

meng, Belsari, Manas, Sankosh and

Teesta

South Tributaries - Dibru, Dihing,

Barak, Dhansari

In Bangladesh - Merges with Teesta

= Jamuna + Ganga = Padma + Barak

= Meghna

Peninsular Rivers

1. Narmada Basin

Origin - Amarkantak Hills, MP

Flows between Vindhyas and

Satpuras

Notable feature - Dhuandhar Fall ,

Marble Rocks (Jabalpur) , Kapildhara

Fall

Sardar Sarovar dam

Note - Luni river rising in Pushkar

Valley is lost in the marshy Rann of

Katchch and doesn’t fall into sea

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Geography

2. Tapi Basin

Origin - Satpuras, MP

Purna is a major tributary

Note - Other main west flowing rivers are:

Sabarmati - Mewar, Aravalli Hills

Mahi - Vindhyas (both drain into

Gulf of Khmbat)

Periyar - Kerala

3. Mahanadi

Origin - Dandakaranya near Sihawa

(Raipur), Chhattisgarh

Flows through Odisha

Other important river in the region is

Brahmani river

4. Godavari

Origin - Trimbuk Plateau, Nashik, MH

Longest River in the South - called

Dakshin Ganga

Major tributaries - Wenganga,

Penganga, Wardha, Manjri, Pranhita,

Indravati

5. Krishna

Origin - Mahabaleshwar, MH

Major tributaries - Tungbhadra, Koyana,

Musi, Bhima

6. Kaveri

Origin - Brahmgiri Range, KN,

Western Ghats

Major tributary - Amravati, Hemvati,

Bhavani

Makes the second biggest waterfall in

India - Sivasamudram

It is a perennial river

Other important river is Vaigai in TN

7. Others

Longest river of Kerala - Bharathpuza,

rises near Annamalai Hills

Shravati river in KN makes Jog or

Gersoppe Falls - highest in India

Two major rivers of Goa - Mandovi

and Juari

Most small rivers in Kerala flow westwards, but Bhavani flows eastwards

GEOGRAPHY OF TAMILNADU

Tamil Nadu is the eleventh largest

state in India and covers an area of

130,058 square kilometres (50,216

sq mi).

It is bordered by Kerala to the west,

Karnataka to the northwest, Andhra

Pradesh to the north, the Bay of

Bengal to the east and the Indian

Ocean to the south.

Cape Comorin (Kanyakumari), the

southernmost tip of the Indian

Peninsula which is the meeting point

of the Arabian Sea, the Bay of Bengal,

and the Indian Ocean.

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Geography

Seasons of Tamilnadu

Summer

The summer in Tamil Nadu runs

throughout March,April and May and is

characterized by intense heat and scant

rainfall across the state.

Winter

The cold weather commences early in

December and comes to an end in the

middle of March. The climate in the cold

weather is pleasant. The days are bright

and sunny the sun is not too hot.

As soon as the sun sets the temperature

falls and the heat of the day yields place to

cooler weather.

Monsoon

The state has three distinct periods of

rainfall: advance rainfall ; rainfall from

the tropical cyclones emerging in the

neighbourhood of the Andaman islands

during the Retreat of Monsoons(October–

November); and the North East monsoon

during the months of October–December,

with dominant northeast monsoon winds

from the western disturbances emerging

over the Mediterranean Sea. The dry

season is from February to early June.

Tamil Nadu has rain during the

monsoon season due to the southwest

trade winds which blow towards the

northern hemisphere. Tamil Nadu receives

rainfall in the winter season due to

northeast trade winds. The normal annual

rainfall of the state is about 945 mm (37.2

in) of which 48% is through the North East

monsoon,and 32% through the South

West monsoon. Since the state is entirely

dependent on rains for recharging its water

resources, monsoon failures lead to acute

water scarcity and severe drought.

Tamil Nadu is classified into seven aggro-climatic zones: north-east, north-

west, west, southern, high rainfall, high

altitude hilly,and Cauvery Delta (the most

fertile agricultural zone).

Coastline of Tamil Nadu

The Coastline of Tamil Nadu is located

on the southeast coast of Indian Peninsula,

and forms a part of Coromandel Coast

of Bay of Bengal and Indian Ocean. It

is 1,076 km (669 mi) long and is the

second-longest coastline in the country

after Gujarat.Chennai, the capital of the

state and an important commercial and

industrial center in the country is located

in the northern part of the coast with

Kanniyakumari, forming the southern

tip where Indian Ocean, Bay of Bengal

and Arabian Sea meet. It also shares

maritime border with Sri Lanka across the

Palk strait in Gulf of Mannar. The coastal

corridor consists of 13 districts with 15

major ports and harbors, sandy beaches,

lakes and river estuaries.

The coastal stretch extends for 1,076

km (669 mi) from Pazhaverkadu of

Thiruvallur district to Ezhudesam of

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Geography

Kanniyakumari district. Kanniyakumari,

forms the southernmost tip of the Indian

subcontinent where Indian Ocean, Bay of

Bengal and Arabian Sea meet. Pamban

Islandforms part of Ramanathapuram

district separating Gulf of Mannar and

Palk strait with the Ram Setu connecting

it with Sri Lanka.

There are 13 districts that share the

coastline namely Thiruvallur, Chennai,

Kanchipuram, Villupuram, Cuddalore,

Thiruvarur, Nagapattinam, Thanjavur,

Pudukottai, Ramanathapuram,

Thoothukudi, Tirunelveli and

Kanyakumari.

••••••

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Geography

The bulk of our food and much of our

clothing is derived from land-based crops

that grow in the soil. The soil on which we

depend so much for our day-to-day needs

has evolved over thousands of years. The

various agents of weathering and gradation

have acted upon the parent rock material

to produce a thin layer of soil.

Soil is the mixture of rock debris

and organic materials which develop on

the earth’s surface. The major factors

affecting the formation of soil are relief,

parent material, climate, vegetation and

other life-forms and time. Besides these,

human activities also influence it to a large extent. Components of the soil are mineral

SOIL ReSOuRceS

particles, humus, water and air. The actual

amount of each of these depends upon the

type of soil. Some soils are deficient in one or more of these, while there are some

others that have varied combinations.

Soil Profile:If we dig a pit on land and look at the

soil, we find that it consists of three layers which are called horizons.

This arrangement of layers is known as

the soil profile. Underneath these three horizons is the rock which is also known

as the parent rock or the bedrock.

‘Horizon A’ is the topmost zone, where

organic materials have got incorporated

with the mineral matter, nutrients and

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Geography

water, which are necessary for the growth

of plants.

‘Horizon B’ is a transition zone

between the ‘horizon A’ and ‘horizon C’,

and contains matter derived from below

as well as from above. It has some organic

matter in it, although the mineral matter

is noticeably weathered.

‘Horizon C’ is composed of the loose

parent material. This layer is the first stage in the soil formation process and

eventually forms the above two layers.

Classification of Soils: On the basis of genesis, colour,

composition and location, the soils of India

have been classified into:(i) Alluvial soils

(ii) Black soils

Forest Soils

Alluvial Soils

Red & Yellow Soils

Block Soils

Laterite Soils

Arid Soils

ICAR has classified the soils of India into the following order as per the USDA soil

taxonomySl.

No

Order Area

(in Thousand

Hectares)

Percent-

age

1. Inceptisols 130372.90 39.74

2. Entosils 92131.71 28.08

3. Alfosols 44448.68 13.55

4. Vertisols 27960.00 8.52

5. Aridisols 14069.00 4.28

6. Ultisols 8250.00 2.51

7. Mollisols 1320.00 0.40

8. Others 9503.10 2.92

Total 100

Sourse : Soils of India. National Bureau of Soil Survey and Land Use Planning. Publication

Number 94

(iii) Red and Yellow soils

(iv) Laterite soils

(v) Arid soils

(vi) Saline soils

(vii) Peaty soils

(viii) Forest soils

Alluvial Soils:Areas of Occurrence: Alluvial soils are

widespread in the northern plains and the

river valleys. These soils cover about 40

per cent of the total area of the country.

Through a narrow corridor in Rajasthan,

they extend into the plains of Gujarat. In

the Peninsular region, they are found in

deltas of the east coast and in the river

valleys. The alluvial soils vary in nature

from sandy loam to clay.

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Geography

In the Upper and Middle Ganga plain, two different types of alluvial soils have

developed, viz. Khadar and Bhangar.

Khadar is the new alluvium and is

deposited by floods annually, which enriches the soil by depositing fine silts. Bhangar represents a system of older

alluvium, deposited away from the flood plains. Both the Khadar and Bhangar soils

contain calcareous concretions (Kankars).

Characteristics: They are depositional soils,

transported and deposited by rivers and streams. They are generally rich in

potash but poor in phosphorous.

These soils are more loamy and clayey

in the lower and middle Ganga plain

and the Brahamaputra valley. The sand

content decreases from the west to east.

The colour of the alluvial soils varies

from the light grey to ash grey. Its shades depend on the depth of the deposition, the texture of the materials, and the time

taken for attaining maturity. Alluvial soils

are intensively cultivated.

Black Soil:Areas of Occurrence: Black soil covers

most of the Deccan Plateau which includes

parts of Maharashtra, Madhya Pradesh,

Gujarat, Andhra Pradesh and some parts

of Tamil Nadu. In the upper reaches of the

Godavari and the Krishna, and the north

western part of the Deccan Plateau, the

black soil is very deep.

Characteristics: These soils are also

known as the ‘Regur Soil’ or the ‘Black

Cotton Soil’. The black soils are generally

clayey, deep and impermeable.

They swell and become sticky when

wet and shrink when dried. So, during

the dry season, these soil develop wide

cracks. Thus, there occurs a kind of ‘self

ploughing’. Because of this character of

slow absorption and loss of moisture,

the black soil retains the moisture for a

very long time, which helps the crops,

especially, the rain fed ones, to sustain

even during the dry season.

Chemically, the black soils are rich in lime, iron, magnesia and alumina. They also contain pot-ash. But they lack in phosphorous, nitrogen and organic matter. The

colour of the soil ranges from deep

black to grey.

Red and Yellow Soil:Areas of Occurrence:

RED SOIL YELLOW SOIL

Eastern and

Southern part

of the Deccan

Plateau. Along the

piedmont zone of

the Western Ghat,

long stretch of area

is occupied by red

loamy soil.

Yellow and red

soils are also

found in parts

of Orissa and

Chattisgarh and

in the southern

parts of the middle

Ganga plain.

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Geography

Characteristics:

RED SOIL YELLOW SOIL

Red soil develops

on crystalline

igneous rocks

in areas of low

rainfall.

The soil develops

a reddish colour

due to a wide

diffusion of iron

in crystalline and

metamorphic

rocks. It looks

yellow when

it occurs in a

hydrated form.

The fine-grained red and yellow soils are

normally fertile, whereas coarse-grained

soils found in dry upland areas are poor

in fertility. They are generally poor in

nitrogen, phosphorous and humus.

Laterite SoilLaterite has been derived from the Latin

word ‘Later’ which means brick.

Areas of Occurrence:

These soils have mainly developed in

the higher areas of the Peninsular plateau.

The laterite soils are commonly found in

Karnataka, Kerala, Tamil Nadu, Madhya

Pradesh and the hilly areas of Orissa and

Assam.

Characteristics :

The laterite soils develop in areas with

high temperatureerature and high rainfall.

These are the result of intense leaching

due to tropical rains. With rain, lime and

silica are leached away, and soils rich in

iron oxide and aluminium compound are

left behind. Humus content of the soil is

removed fast by bacteria that thrives well

in high temperature.

These soils are poor in organic matter, nitrogen, phosphate and calcium, while iron oxide and potash are in excess. Hence, laterites are not suitable

for cultivation; however, application of

manures and fertilisers are required for

making the soils fertile for cultivation.

Red laterite soils in Tamil Nadu, Andhra

Pradesh and Kerala are more suitable for

tree crops like cashewnut. Laterite soils

are widely cut as bricks for use in house

construction.

Arid Soils:Areas of Occurrence :

Arid soils are characteristically

developed in western Rajasthan, which

exhibit characteristic arid topography.

Characteristics:

They occur in arid and semi-arid regions,

and in waterlogged and swampy areas.

Sea water intrusions in the deltas

promote the occurrence of saline soils.

Arid soils range from red to brown

in colour. They are generally sandy in

structure and saline in nature. In some

areas, the salt content is so high that

common salt is obtained by evaporating the

saline water. Due to the dry climate, high

temperature and accelerated evaporation,

they lack moisture and humus. Nitrogen

is insufficient and the phosphate content is normal. Lower horizons of the soil are

occupied by ‘kankar’ layers because of the

increasing calcium content downwards.

The ‘Kankar’ layer formation in the

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Geography

bottom horizons restricts the infiltration of water, and as such when irrigation is made available, the soilmoisture is readily available for a sustainable plant growth. These soils are poor and contain little humus and organic matter.

Saline Soils:Areas of Occurrence :

Saline soils are more widespread in

western Gujarat, deltas of the eastern

coast and in Sunderban areas of West

Bengal. In the Rann of Kuchchh, the

Southwest Monsoon brings salt particles

and deposits there as a crust.

Characteristics:

Saline soils contain a larger proportion of sodium, potassium and magnesium, and thus, they are infertile, and do not support any vegetative growth. They have more salts,

largely because of dry climate and poor

drainage. Their structure ranges from

sandy to loamy. They lack in nitrogen and calcium.

In the areas of intensive cultivation

with excessive use of irrigation, especially

in areas of green revolution, the fertile

alluvial soils are becoming saline. Excessive

irrigation with dry climatic conditions

promotes capillary action, which results

in the deposition of salt on the top layer of

the soil. In such areas, especially in Punjab

and Haryana, farmers are advised to add

gypsum to solve the problem of salinity in

the soil.

Peaty Soils:Areas of Occurrence

It occurs widely in the northern part of

Bihar, southern part of Uttaranchal and the coastal areas of West Bengal, Orissa

and Tamil Nadu.

Characteristics

They are found in the areas of heavy

rainfall and high humidity, where there

is a good growth of vegetation. Thus,

large quantity of dead organic matter

accumulates in these areas, and this gives

a rich humus and organic content to the

soil. Organic matter in these soils may go

even up to 40-50 per cent. These soils are

normally heavy and black in colour. At

many places, they are alkaline also.

Forest Soils

As the name suggests, forest soils are

formed in the forest areas where sufficient rainfall is available. The soils vary in

structure and texture depending on the

mountain environment where they are

formed. They are loamy and silty on valley

sides and coarse-grained in the upper

slopes. In the snow-bound areas of the

Himalayas, they experience denudation,

and are acidic with low humus content. The

soils found in the lower valleys are fertile.

It is evident from the foregoing discussions

that soils, their texture, quality and nature

are vital for the germination and growth

of plant and vegetation including crops.

Soils are living systems. Like any other

organism, they too develop and decay, get

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Geography

degraded, respond to proper treatment if

administered in time. These have serious

repercussions on other components of

the system of which they themselves are

important parts.

National Green Tribunal Act, 2010

to provide for the establishment of

a National Green Tribunal for the

effective and expeditious disposal

of cases relating to environmental

protection and conservation of forests

and other natural resources.

Public Liability Insurane Act 1991

The Water (prevention and control of

pollution) Act was enacted in 1974.

The Act was amended in 1988.

The water (prevention and control of

pollution) cess Act was enacted in

1977. The Act was amended in 2003.

TAMILNADU SYMBOLSSl.

No.

CATEGORY NAME

1. Government

Symbol

Srivilliputhur

Aandal Temple

Tower

2. State Animal Nilgiri Tahr

3. State Bird Emerald dove

4. State Flower Gloriosa lily

5. State Tree Palm Tree

6. State Fruit Jack Fruit

7. State Sport Kabadi

8. State Dance Bharatanatyam

••••••

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Geography

A mineral is a natural substance of

organic or inorganic origin with definite chemical and physical properties. A

rock which has large concentration of a

particular mineral is called the ore of that

mineral.

Characteristics of minerals:

1. They are unevenly distributed over

the surface of the Earth.

2. No country in the world is self-

sufficient in all the minerals.3. Most of the minerals have

impurities.

4. Minerals are exhaustible.

MINERALS IN INDIA

Various stages of development

have been named after minerals,

such as:

1. The Stone Age: Man made weapons

and implements from stones.

2. Copper was probably the first metal that man learnt to mine and with its

use started the Copper Age.

3. The Bronze Age started when man

developed a stronger and more

durable metal by mixing copper

and tin.

4. About 3000 years ago, the Bronze

Age was replaced by the lron Age.

5. Iron Age came to be replaced by the

Steel Age in the modern times.

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Geography

Metallic minerals:

The metallic minerals contain metals

such as iron, copper, manganese, bauxite,

gold, etc. The metallic minerals are further

divided into:

a. Ferrous minerals, which have iron

contents, such as iron, manganese,

nickel, cobalt, tungsten, etc.

b. Non-ferrous minerals do not have

from contents, such as gold, silver,

copper, bauxite, etc.

Non-metallic minerals:

a) The non-metallic minerals do not

contain metals, such as mica,

limestone, gypsum, potash, coal.

b) Some non-metallic minerals are also

regarded as the mineral fuels, such

as coal and petroleum.

Distribution of Minerals

It has been estimated that nearly

100 different minerals are known to be

produced in our country,out of which 30

may be considered quite important. Most

of the metallic minerals are found in the

peninsular plateau region, especially in

the old crystalline rocks. The minerals

are generally concentrated in three belts.

There may be some occurrences here and

there in isolated pockets.

The three belts are as under: The

Northeastern Plateau region, the

Southwestern Plateau region and the

Northwestern region.

Iron Ore:

Iron is the backbone of modern

civilization and is a metal of universal use.

It is a durable and cheap metal which can

be moulded in different forms and can be

mixed with other metals to form alloys. Iron

is not found in pure form. It is often mixed

with lime, magnesium, phosphorous,

silicon, etc.

NAME CHARACTERISTICS IRON CONTENT

Haematite It is reddish in color, so it is also known as red-

ochre.

60-70%

Magnetite The color of the ore is dark brown to blackish and is

known as black ore. It has magnetic properties.

70%

Limonite It is yellow or light brown in color. It is called hydrated

iron oxide, when the iron ore in mixed with oxygen

and water. Its mining is easier and cheaper.

40- 60%

Siderite It is an inferior variety of iron ore and has many

impurities. It is also called iron carbonate.

20- 40%

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Geography

Reserves of Iron Ore

India has about 20 per cent of the

world’s total reserves of iron ore. About 75

per cent of the total reserves of the iron ore

in India are of haematite grade.

Jharkhand, Orissa, Karnataka, Madhya

Pradesh, Chattisgarh and Goa, have about

97 per cent of the total iron ore reserves of

India.

State/Area Percentage of the

Reserves

1. Jharkhand 25.7

2. Orissa 21.6

3. Karnataka 20.7

4. MP-Chattisgarh 18.5

5. Goa 10.5

6. Maharashtra 1.8

7. Others 1.2

AREAS OF IRON ORE

PRODUCTION

Today India is the largest producer

of iron ore in Asia and seventh largest

producer in the world. Most of the iron

ore mined in India are of Haematite and

Magnetite varieties. These ores have

high percentage of iron contents and low

sulphur contents.

Madhya Pradesh-Chattisgarh: Durg,

Bastar and Jabalpur districts. Bailadila

range in Bastar and Dhalli-Raihara range

in Durg are the main producing regions.

Raigarh, Bilaspur, Mandla, Balagat and

Surguja districts.

Jharkhand: PurviSinghbhum, Paschimi

Singhbhum and Palamau districts, at

Charia in Singhbhum district. A major

part of the iron ore production goes to

Rourkela, Bokaro, and IISCO steel plants.

The exports are mainly through Haldia

port.

Karnataka: The bulk of the production

(more than 90 per cent) comes from

Bellary district, followed by Chitradurga,

Chikmagalur, Bijapur, Tumkur, etc. The

state is the second largest producer of iron

ore in India.

Goa: It is the third largest producer

of iron ore and most of the production

comes from the mines in North Goa.

The ore is of inferior quality. Almost the

entire production from Goa is exported to

Japan.

Orissa: The high grade haematite variety

of iron ore is found in the Mayurbhanj,

Keonjhar and Sundargarh districts. The

other producing districts or areas are

Sambalpur, Cuttack and Korapur.

Andhra Pradesh: The main iron ore

producing centres are in the districts

of Anantapur, Khammam, Kurnool,

Cuddapah, Krishna and Nellore.

Tamil Nadu: Most of iron ore with 35

to 50 per cent of iron contents are found

in Salem, North Arcot, Tiruchchirappalli,

Coimbatore and Madurai districts.

Others:

Some production of iron ore is from

Ratnagiri, Chandrapur, Satara and Bandara

districts in Maharashtra; Bhilwara and

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Geography

Udaipur districts in Rajasthan; Junagarh

and Bhavnagar districts in Gujarat;

Mahendragarh district in Haryana;

Rajauri, Jammu and Udhampur districts

in Jammu and Kashmir; and in some

parts of Uttarakhand, Uttar Pradesh, and

Himachal Pradesh.

Trade of Iron Ore:Exported to Japan, South Korea, East

European Countries and the Gulf region.

The main ports handing the export are

Marmugao, Vishakhapatanam, Paradip,

Mangalore, Haldia and Chennai.

Manganese:

Manganese is a black hard and iron-like

metal, which is widely used in the making

of iron and steel and in the manufacture

of ferro-manganese alloys. It is also used

in the manufacture of bleaching powder,

dry cell batteries, enamel, insecticides,

plastics, glazed potteries, matches, glass

and chemical industries.

Occurrence and Reserves of Manganese

In India

The highest occurrence of manganese

ore in India is found in the Dhawar system

of rocks. India has 20 per cent of the total

known reserves in the world. The main

reserves are in Karnataka, Orissa, Madhya

Pradesh, Maharashtra and Goa. Some

reserves also occur in Andhra Pradesh,

Jharkhand, Gujarat, Rajasthan and West

Bengal.

Areas of Manganese Production in

India

India is the fifth largest producer of manganese in the world, after Brazil,

Gabon, South Africa and Australia.

There are three main areas of manganese

production in our country.

1. The northeastern region,

comprising Orissa and Jharkhand.

The reserves are about 19 per cent

and the production is about 33 per

cent.

2. The central region, comprising

Madhya Pradesh and north

Maharashtra. The reserves are about

15 per cent and the production is

about 39 per cent.

3. The peninsular region, comprising

Karnataka, Andhra Pradesh, Goa

and south Maharashtra. The

reserves are about 45 per cent and

the production is about 30 per cent.

Orissa:

It is the largest producer (33 per cent)

of manganese in the country. The ore has

high iron and low phosphorus contents.

Districts: Keonjhar, Sundargarth,

Korapur, Kalahandi, Mayurbhanj, Talcher

and Bolangir districts.

Madhya Pradesh:

It is the third largest producer (20 per

cent) of manganese in the country. The

main producing districts are Balaghat,

Chhindwara, Jabalpur and Jhabua. Small

deposits are also found in Dewas, Sehore

and Nimar districts.

Karnataka:

With largest reserves of manganese, the

state is the fourth largest producer (14 per

cent) in the country.

Districts: Bellary is the most important

producer followed by Shimoga, Chitradurga,

Tumkur and Belgaum districts.

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Geography

Others:

The other producing states are Andhra

Pradesh (Srikakulam and Vishakhapatnam

districts), Rajasthan, Goa, Gujarat,

Jharkhand, Tamil Nadu and West Bengal.

Bauxite:

Bauxite, a clay-like substance, is the

ore of aluminium. Due to its lightness,

strength, malleability, ductility, heat and

electrical conductivity and resistance to

atmospheric corrosion, aluminium has

become one of the most useful metals in

the present age. Converting bauxite into

aluminium, depends on the availability of

cheap and enough electricity.

Reserves of Bauxite in India:

The Indian reserves of bauxite are the

fifth largest in the world after Guinea, Australia, Brazil and Vietnam. More than

half of India’s bauxite reserves are in

Orissa and Andhra Pradesh states.

Recently extensive deposits of bauxite

have been discovered in the Jammu and

Poonch areas of the Jammu and Kashmir

state. The other states which have rich

reserves of bauxite are Jharkhand,

Madhya Pradesh, Gujarat, Maharashtra,

Karnataka, Tamil Nadu, Kerala, Goa and

Uttar Pradesh.

Areas of Bauxite Production

About 90 per cent of bauxite in our

country is of metallic grade. There has been

a significant progress in the production of bauxite in India.

Orissa, Jharkhand, Bihar, Gujarat,

Maharashtra, Madhya Pradesh,

Chattisgarh and Tamil Nadu.

Limestone

Limestone (calcium carbonate) is

associated with rocks composed of

carbonate of calcium and magnesium or

mixture of the two. Limestone deposits are

of sedimentary origin and exist in almost

all geological formations except in the

Gondwana region.Of the total consumption,

75 per cent is used in cement industry, 16

per cent in iron and steel industry, 4 per

cent in chemical industry and the rest in

paper, sugar, fertilizers, ferro-manganese,

glass and rubber industries.

Areas of Limestone Production

Almost all the states in India produce

some quantities of limestone, but about

75 per cent of the total production comes

from Madhya Pradesh, Chattisgarh,

Andhra Pradesh, Rajasthan, Gujarat and

Karnataka

Coal:

Coal, a mineral fuel, is the main

source of energy in India. Coal is an

organic substance, composed mainly of

hydrocarbons, found in the sedimentary

rocks. In the geological past, large areas

under thick forests were buried under

the sediments. The heat and pressure of

the overlying sediments together with the

earth movement led to the formation of

coal. Coal’s capacity to give energy depends

upon its carbon content.

Types of Coal

Coal can be grouped in four types,

such as peat, lignite, bituminous and

anthracite.

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Geography

Type Carbon

Content

Characteristics Occurence

PEAT less than 40 % It has a high percentage of

moisture and volatile matter. It

leaves a large amount of ash.

LIGNITE 40- 60% Lignite is soft, but more compact

than peat. It has large percentage

of moisture and less amount of

combustible matter.

Rajasthan, Tamil

Nadu, Assam

and Jammu and

Kashmir

BITUMINOUS 60- 80% The moisture and the volatile

contents are also less. In this type

of coal is also known bunker coal

to the sailors. It is widely used in

the making of coke and gas. Coke

is mainly used in the iron and

steel industry for smelting iron

ore in blast furnaces.

J h a r k h a n d ,

Orissa, West-

Bengal, Madhya

Pradesh and

Chhattisgarh.

ANTHRACITE 80- 90% It has no volatile matter. It

does not ignite easily, but once

lighted, it has the highest heating

capacity. It burns for a long time

and leaves very little ash behind.

Only in Jammu

and Kashmir,

and that too

in very small

quantity.

Occurrence of Coal in India:

The coalfields in India are classified into two groups:

1. The Gondwana Coalfields: Mostly in river valleys, such as Damodar,

Mahanadi, Son, Godavari,

Wardha, Narmada, etc.

2. The Tertiary Coalfields: Assam, Meghalaya, Tamil Nadu, Rajasthan,

Gujarat and Arunachal Pradesh.

Rapid industrial development after

independence gave a great boost to coal

production in India. It further increased

after the nationalization of coal mines

in 1972 and the formation of Coal India

Ltd. in 1975.

Coal Production in India

India is the fourth largest coal producer

in the world.

About 80 percent of the coal deposits

in India is of bituminous type, and is of

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Geography

non-cooking grade. About 75 percent of

lignite production comes from Neyveli

in Tamil Nadu and the rest from

Kachchh district of Gujarat.

Problems of Coal Mining In India

Coal distribution is highly uneven

throughout India.

Coal-consuming industries have to

pay a high price for coal.

Much of the Indian coal is non-

coking grade. This is unsuitable for

metallurgical industries.

The problem in transportation arises

due to lack of railway facilities,

variation in gauges, shortage

of wagons, slow movement of

trains, pilferage, etc.

The coal mining techniques are old

and outdated.

Coal dust in the mines near the pit-

heads

Create environmental pollution.

The safety measures are expensive.

There are heavy losses due to

pilferage, and fire in the coal mines and at pit-heads.

Power shortage.

Petroleum

Petroleum is found in the underground

reservoirs associated with sedimentary

rocks. In some reservoirs the mineral oil

is found in association with natural gas.

Petroleum is a compact and convenient

fuel, which has revolutionized land, air

and water transportation. It can be easily

transported through pipelines from the

producing centres to the consuming

areas.

Origin and Occurrence of Petroleum

The crude petroleum deposits are found

only in the sedimentary rock basins of

marine origin. But all sedimentary rocks

do not contain mineral oil. Petroleum has

an organic origin and is formed by the

gradual decay and compression of various

marine deposits.

They remain buried for millions of years

and the decomposition of the organic

matter has led to the formation of mineral

oil.

Reserves of Petroleum in India

1. The Terai zone running parallel to

the Himalayas from Jammu and

Kashmir to Assam.

2. River basins of Ganga, Satluj, etc.

including deltaic tracts of Ganga,

Mahanadi, Godavari, Krishna and

Kaveri.

3. The continental shelf along the

Western Coast, Gulf of Cambay, and

the islands in the Arabian Sea and

the Bay of Bengal.

Areas of Petroleum Production

Until 1953, Digboi was the sole

producer of mineral oil in India. There are

four main petroleum producing regions in

our country.

1. Two of them are on-shore-the

Brahmaputra valley and the Gujarat

Coast.

2. The other two are off-shore-the

western coast off-shore oilfields and the

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Geography

eastern coast off-shore

oilfields. About two-third of the total petroleum

production in India comes from the off-

shore oilfields.

The Brahmaputra Valley

It is the oldest oil producing region in

India. The main oil producing fields are at Digboi, Moran-Hugrijan, NaharKatiya,

Rudrasagar, Surma Valley, etc. in the

districts of Dibrugarh and Sibsagar in

Assam.

The crude petroleum from Digboi is sent

to Digboi refinery and from NaharKatiya to Noonmati and Barauni refineries. The Moran-Hugrijan is located 40 km

southwest of NaharKatiya. The crude oil

is sent to the Barauni refinery. Some oil-fields have been located in Tripura and Arunachal Pradesh.

The Gujarat Coast

This is the second largest petroleum

producing area in India. This area has two

distinct oil-bearing belts-Gulf of Cambay

(Cambay and Ankleshwar) and the area

from Kaira to Mehsana (Kalol, Navgam,

Bacharji and Mehsana).

The Cambay oil-fields lie about 60 km west of Vadodara. The crude oil has less

sulphur and more wax. The commercial

production in the Ankleshwar region

started in 1961. The petroleum is rich

in kerosene and gasoline. The entire

production is sent to Kovali and Trombay

refineries. The Ahamedabad - Kalol area is located towards the north of the Cambay

basin. The other oil-fields are in Kosamba, Kathana, Sanad, Dholka, Bakrol, Kadi,

etc.

The Off-Shore OilfieldsKuchchh, Khambat, Konkan, Malabar

Coast, Coromandel Coast, Sundarbans

and Krishna-Godavari delta.

The West Coast off-shore oilfields

the ONGC has discovered oilfields at Mumbai High(1974, The petroleum has a

higher percentage of petrol and kerosene),

Bassein and Aliabet.

The Eastern the Coast Off-shore

Oilfields Petroleum and natural gas

have been discovered in the basin and

delta regions of Godavari, Krishna and

Kaveri rivers. These oil fields are likely to contribute to about 3 to 4 million tonnes

of crude oil every year.

Reserves of crude oil have also been

discovered in Bilaspur (UP), Jawalamukhi

(Punjab), Barmer (Rajasthan), etc.

Oil RefineriesThe first oil refinery was commissioned

at Digboi (Assam) in 1901, with a capacity

of two lakh tonnes per year.

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Geography

OIL REFINERIES IN INDIA

Refinery State Year of

commissioning

1. Digboi (IOC) Assam 1901

2. Trombay (HPCL) Maharashtra 1954

3. Trombay (BPCL) Maharashtra 1955

4. Vishakhapatnam (HPCL) Andhra Pradesh 1957

5.Noonmati (IOC) Assam 1962

6. Barauni (IOC) Bihar 1964

7. Koyali (IOC) Gujarat 1965

8. Kochi (BPCL) Kerala 1966

9. Chennai (IOC) Tamil Nadu 1969

10. Haldia (IOC) West Bengal 1975

11. Bongaigaon (IOC) Assam 1979

12. Mathura (IOC) Uttar Pradesh 1982

13. Mangalore (MRPL) Karnataka 1996

14. Jamnagar (RIL) Gujarat 1999

15. Panipat (IOC) Haryana 1997

16. Tatipaka Andhra Pradesh

17. Nagapattinum Tamil Nadu

••••••

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Geography

Resources are a function of human

activities. Human beings themselves

are essential components of resources.

They transform material available in

our environment into resources and use

them.

These resources can be classified in the following ways –

(a) On the basis of origin – biotic and

abiotic

(b) On the basis of exhaustibility –

renewable and non-renewable

(c) On the basis of ownership –

individual, community, national

and international

(d) On the basis of status of

development – potential, developed

stock and reserves.

TYPES OF RESOURCES

On the Basis of Origin

Biotic Resources: These are obtained

from biosphere and have life such as

human beings, flora and fauna, fisheries, livestock etc.

NATURAL RESOURCES

Abiotic Resources: All those things

which are composed of non-living things

are called abiotic resources. For example,

rocks and metals.

On the Basis of Exhaustibility

Renewable Resources: The resources

which can be renewed or reproduced by

physical, chemical or mechanical processes

are known as renewable or replenishable

resources. For example, solar and wind

energy, water, forests and wildlife, etc. The

renewable resource may further be divided

into continuous or flow . Non-Renewable Resources: These occur

over a very long geological time. Minerals

and fossil fuels are examples of such

resources. These resources take millions

of years in their formation. Some of the

resources like metals are recyclable and

some like fossil fuels cannot be recycled

and get exhausted with their use.

On the Basis of Ownership

Individual Resources: These are also

owned privately by individuals. Many

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Geography

farmers own land which is allotted to

them by government against the payment

of revenue. In villages there are people

with land ownership but there are many

who are landless. Urban people own plots,

houses and other property. Plantation,

pasture lands, ponds, water in wells etc.

are some of the examples of resources

ownership by individuals.

Community Owned Resources: There

are resources which are accessible to all

the members of the community. Village

commons (grazing grounds, burial

grounds, village ponds, etc.) public parks,

picnic spots, playgrounds in urban areas

are de facto accessible to all the people

living there.

Natural Resources in India

India is endowed with different types

of natural Resources such as fertile

soil, forests, minerals and water. These

resources are unevenly distributed.

The various types of different Natural

Resources of India is discussed below:

Soil Resource:

India has a large proportion of well

watered fertile lands. In the alluvial soil

of the Northern Great Plains of the Sutlej-

Ganga plains and Brahmaputra Valley

wheat, rice, maize, sugarcane, jute, cotton,

rapeseed, mustard, sesumum, linseed,

etc. are grown in abundance.

In the black soil of Maharashtra, Andhra

Pradesh, Tamil Nadu, Gujarat cotton and

sugarcane are grown.

The improper use of soil destroys

its composition, texture and structure

Unscientific irrigation causes capillary action making soil alkaline and unsuitable

for cultivation. The proper management of

soil is important for soil conservation in

India.

Mineral Resource:

India is quite rich in some minerals

like iron, coal, mineral oil, manganese,

bauxite, chromite, copper, tungsten,

gypsum, limestone, mica and so on.

A number of organizations like Geological

Survey of India, Indian Bureau of Mines,

etc. are engaged in the exploration and

development of mineral resource in India.

Livestock Resource:

Hills, mountains and less fertile lands

are put under pasture. Scientific methods are followed in rearing cattle. India

maintains rich domestic animal diversity.

India has a good population of goat,

sheep, poultry, cattle, buffalo, etc. Indian

livestock plays a vital role in improving

the socio-economic status of the rural

masses.

Reduce: This means that you use

less. You save electricity by switching off

unnecessary lights and fans. You save

water by repairing leaky taps. You do

not waste food.

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Geography

Recycle: This means that you collect

plastic, paper, glass and metal items

and recycle these materials to make

required things instead of synthesising

or extracting fresh plastic, paper, glass

or metal. In order to recycle, we first need to segregate our wastes so that

the material that can be recycled is not

dumped along with other wastes.

Reuse: This is actually even better

than recycling because the process of

recycling uses some energy. In the ‘reuse’

strategy, you simply use things again

and again. Instead of throwing away

used envelopes, you can reverse it and

use it again. The plastic bottles in which

you buy various food-items like jam or

pickle can be used for storing things in

the kitchen.

Horticulture:

Diverse agro-climatic conditions in India

facilitate cultivation of a large number of

horticulture crops such as vegetables,

fruits, flower, medicinal and aromatic plant, mushroom, etc. and plantation

corps like tea, coffee and rubber.

They provide opportunities for growing

spices.

Fisheries:

Fish production has been showing

increasing trend. India is one of the leading

fish producer.

Forest Resource:

India possesses a variety of natural

vegetation since the country has a varied

relief and climate. These forests are confined to the plateaus and hilly mountainous

areas. India has a great variety of fauna.

There are many national parks and

hundreds of wild life sanctuaries.

Forests are called ‘green gold’. They

are renewable resources. They provide

quality environment. They eat up CO2, the

poisons of urbanization, industrialization,

explosion of population, etc. They regulate

climate as they act as natural ‘sponge’.

Arresting soil erosion, increasing soil

fertility growing forest based industries,

providing medicinal herbs, animal habitats,

cattle fodder, domestic fuel and foreign

exchange they contribute substantially to

Indian economy.

Unfortunately India’s forest cover is

diminishing at an alarming rate. So,

various measures for afforestation have

been introduced.

The forest (conservation) Act 1980 was

made in India. No forest can be diverted

for non-forest purpose.

The Forest Research Institute was

established at Dehradun for research

in forestry development. Cutting trees

selectively, planting new trees, protecting

trees, observing world Forestry Day every

March 21 by planting trees, etc. are the

schemes of afforestation.

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Geography

Natural vegetation refers to a plant

community that has been left undisturbed

over a long time, so as to allow its

individual species to adjust themselves

to climate and soil conditions as fully as

possible. India is a land of great variety

of natural vegetation. Himalayan heights

are marked with temperate vegetation;

the Western Ghats and the Andaman

Nicobar Islands have tropical rain forests,

the deltaic regions have tropical forests

and mangroves; the desert and semi

desert areas of Rajasthan are known for

cactii, a wide variety of bushes and thorny

vegetation. Depending upon the variations

NATURAL VEGETATION

in the climate and the soil, the vegetation of

India changes from one region to another.

On the basis of certain common features

such as predominant vegetation type and

climatic regions, Indian forests can be

divided into the following groups:

Types of forests

(i) Tropical Evergreen and Semi

Evergreen forests

(ii) Tropical Deciduous forests

(iii) Tropical Thorn forests

(iv) Montane forests

(v) Littoral and Swamp forests.

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Geography

Forest

Type

Occurrence Conditions Characteristics Common

trees

Tropical

Evergreen

Western

slope of the

Western Ghats,

hills of the

northeastern

region and the

Andaman and

Nicobar Islands.

Annual

precipitation

of over 200 cm

and

Mean annual

temperature

above 220 C.

They are well

stratified, with layers closer to the ground

and are covered with

shrubs and creepers,

with short structured

trees followed by tall

variety of trees.

Trees reach great

heights up to 60 m

or above. There is no

definite time for trees to shed their leaves,

flowering andfruition.

Rosewood,

mahogony,

aini, ebony,

etc.

Semi Ever

green

forests

They are found

in the less

rainy parts of

the above said

regions.

Annual precip-

itation of over

200 cm and

Mean annual

temperatureer-

ature above

22oC.

They have a mixture

of evergreen and

moist deciduous

trees.

The under growing

climbers provide an

evergreen character to

these forests

White cedar,

hollock and

kail.

Deciduous

forests

These forests

are of two

types:

Moist and Dry

deciduous

forests

Moist

deciduous

forests

These forests

are found in the

northeastern

states along the

foothills of

Himalayas,

eastern slopes

of the Western

Ghats and

Orissa.

Rainfall: 100-

200 cm.

The chief feature of

the moist deciduous

forest is a leafless period in the dry

season.

Trees may reach up to

a height of 30-35 m.

Teak, sal,

shisham,

hurra,

mahua,

amla,

semul,

kusum, and

sandalwood

etc.

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Geography

Dry decidu-

ous forest:

These forests

are found in

rainier areas of

the Peninsula

and the plains

of Uttar Pradesh

and Bihar.

Rainfall: 70-

100 cm.

These forests have a

parkland landscape

with open stretches in

which teak and other

trees interspersed

with patches of grass

are common. As the

dry

season begins, the

trees shed their leaves

completely and the

forest appears like

a vast grassland

with naked trees all

around.

Tendu, pal-

as, amaltas,

bel, khair,

axlewood,

etc.

Tropical

Thorn for-

ests

Semi-arid areas

of south west

Punjab,

Haryana, Rajas-

than, Gujarat,

MadhyaPradesh

and Uttar

Pradesh.

Rainfall: less

than 50 cm.

These consist of a

variety of grasses and

shrubs.

Plants remain leaf-

less for most part of

the year and give an

expression of scrub

vegetation.

Babool, ber,

and wild

date palm,

khair, neem,

khejri,

palas, etc.

Montane forests:

In mountainous areas, the decrease

in temperature with increasing altitude

leads to a corresponding change in

natural vegetation. Mountain forests can

be classified into two types, the northern mountain forests and the southern

mountain forests.

The Himalayan ranges show a

succession of vegetation from the tropical

to tundra, which change in with the

altitude.

Succession of vegetation:

1. Deciduous forests are found in

the foothills of the Himalayas. It is

succeeded by the wet temperature

type of forests between an altitudes

of 1,000-2,000 m. In the higher

hill ranges of northeastern India,

hilly areas of West Bengal and

Uttrakhand, evergreen broad leaf

trees such as oak and chestnut are

predominant.

�

Geography

2. Between 1,500-1,750m, pine

forests are also well-developed in

this zone, with chir pine as a very

useful commercial tree. Deodar,

a highly valued endemic species

grows mainly in the western part of

the Himalayan range

3. At many places in this zone,

temperature grasslands are also

found.

4. But in the higher reaches there is

a transition to Alpine forests and

pastures. Silver firs, junipers, pines, birch and rhododendrons, etc. occur

between 3,000 - 4,000m. However,

these pastures are used extensively

for transhumance by tribes like

the Gujjars, the Bakarwals, the

Bhotiyas and the Gaddis.

The southern slopes of the Himalayas

carry a thicker vegetation cover because

of relatively higher precipitation than

the drier north-facing slopes. At higher

altitudes, mosses and lichens form part of

the tundra vegetation.

The southern mountain forests

include the forests found in three distinct

areas of Peninsular India viz; the Western

Ghats, theVindhyas and the Nilgiris. As

they are closer to the tropics, and only

1,500 m above the sea level, vegetation

is temperature in the higher regions, and

subtropical on the lower regions of the

Western Ghats, especially in Kerala, Tamil

Nadu and Karnataka. The temperature

forests are called Sholas in the Nilgiris,

Anaimalai and Palani hills. Some of the

other trees of this forest of economic

significance include magnolia, laurel, cinchona and wattle. Such forests are

also found in the Satpura and the Maikal

ranges.

Littoral and Swamp forests:

The country’s wetlands have been

grouped into eight categories,

(i) the reservoirs of the Deccan

Plateau in the south together with

the lagoons and other wetlands of

the southern west coast;

(ii) the vast saline expanses of

Rajasthan, Gujarat and the Gulf

of Kachchh;

(iii) freshwater lakes and reservoirs

from Gujarat eastwards through

Rajasthan (Keoladeo National

Park) and Madhya Pradesh;

(iv) the delta wetlands and lagoons of

India’s east coast (Chilka Lake);

(v) the freshwater marshes of the

Gangetic Plain;

(vi) the flood plains of the Brahmaputra; the marshes and swamps in the

hills of northeast India and the

Himalayan foothills;

(vii) the lakes and rivers of the

montane region of Kashmir and

Ladakh; and

(viii) the mangrove forest and other

wetlands of the island arcs of the

Andaman and Nicobar Islands.

�

Geography

Mangroves grow along the coasts in the

salt marshes, tidal creeks, mud flats and estuaries. They consist of a number of salt-

tolerant species of plants. Crisscrossed by

creeks of stagnant water and tidal flows, these forests give shelter to a wide variety

of birds. In India, the mangrove forests

spread over 6,740 sq. km which is 7 per

cent of the world’s mangrove forests. They

are highly developed in the Andaman and

Nicobar Islands and the Sunderbans of

West Bengal. Other areas of significance are the Mahanadi, the Godavari and the

Krishna deltas. These forests too, are

being encroached upon, and hence, need

conservation.

Forest And Wild Life

Technical Terms:

National Parks: National Parks are

the reserved forests where natural

vegetation, natural beauty and

wildlife are preserved in their natural

environment.

Wildlife Sanctuaries: Wildlife

sanctuaries are the portion of the

natural forests where hunting and

poaching of wild animals and birds

are prohibited.

Endangered Species: Species in

danger of extinction are known as

endangered species. Ex: Asiatic

elephant.

Endemic Species: Species which

are found in some specific areas are known as endemic species. Ex:

Andaman wild pig.

Bio-diversity or Biological Diversity

is immensely rich in wildlife and

cultivated species, diverse in form

and function but closely integrated in

a system through multiple network of

interdependencies. Various organism

play different roles of producer,

consumer and decomposers. The

existence of other organism along

with humans depends on these roles.

The existence of millions of living

being simultaneously termed as bio-

diversity.

Flora and Fauna in India: India is

one of the world’s richest countries in

terms of vast range of bio-diversity.

It has about 8% of the total number

of species in the world (estimated

to be 1.6 million). India has 81000

species of fauna and 47000 species

of flora. About 15000 species of flowering plant in fauna are endemic (indigenous) to India.

Acts implemented for Conservation

of Wildlife:

The Indian Wildlife Protection Act

1972: The aim of the programme was

towards protecting the remaining

endangered species by banning

hunting, giving legal protection to

their habitat and restricting wildlife

�

Geography

trade. Central and many state

governments established national

parks and sanctuaries.

Notification under Wildlife Act 1980 and 1986: Several hundred

butterflies, moths, beetles, and one dragonfly have been added to the list of protected species.

Wildlife Act 1990: Plants were added

to the list, starting with six species

for the first time.Project Tiger:

“Project Tiger” was launched in 1973.

At present there are Tiger Reserves in

the country.

Some of the major tiger reserves are:

Corbett National Park,

Uttarakhand

Sundarbans National Park, West

Bengal

Bhandhavgarh National Park,

Madhya Pradesh

Manas Tiger Reserve, Assam

Periyar Tiger Reserve, Kerala

Kanha National Park, Madhya

Pradesh.

Types of Forest and Wildlife Resources:

Reserved Forests: These forests are

regarded as the most valuable from

the point of conservation forests and

wildlife resources concerned.

Protected Forests: These forests

lands are protected from any further

depletion

Unclassed Forests: These are other

forests and westelands. They belong

to both government and private

individuals and communities.

Reserved Forests : 54.4% total

forests land

Protected Forests : 29.2% total

forests land

Unclassed Forests: 16.4% total

forests land

Reserved and Protected forests are

termed as permanent forests.

Involvement of Local Communities

‘Natural Resource’ Management

• Chipko Andolan in Himalayas

successfully resisted deforestation

and encourage Afforestation.

• Beej Bachao Andolan in Tehri and

Navdanya proved adequate levels of

diversified crop production without use of synthetic chemicals.

• In India Joint Forest Management

(JFM) involves local communities

in management and restoration of

degraded forests.

Distribution of Forests:

Madhya Pradesh has the largest

area under permanent forests.

Other states Jammu and Kashmir,

Andhra Pradesh, Uttarakhand,

Kerala, Tamil Nadu, West Bengal and

Maharashtra.

Unclassed forests are situated in

north-eastern states of India and

Gujarat.

�

Geography

Dense forests are found in north-

eastern states, Andaman and Nicobar

Island and Uttarkhand.

Open forests are found in Punjab,

Haryana, M.P., Maharashtra,

Karnataka, Tamil Nadu, Kerala,

Bihar, Chhattisgarh, Jharkhand and

Orissa.

Mangrove forests are found in

Sundarbans Delta and Deltas of

east flowing rivers of the peninsular plateau.

Now dams were built for power

generation, water supply for domestic

and industrial use, flood control, recreation, inland navigation and

fish breeding.Hence dams are called multi-purpose

projects.

Examples: Bhakra Nangal Project,

Hirakud Project.

Multi-purpose projects were launched

after independence.

These were proclaimed as ‘temples of

modern India’.

••••••

�

Geography

Net sown area: 46%

Forest: 23%

Area not available for cultivation: 14%

Fallow land (Land out of cultivation for

1 to 5 years): 8%

Agricultural land (net sown area+ fallow

land): 54%

Waste land: 5%

Pastures and tree crops: 5%

Intensity of cropping = (Total cropped

area/ Net sown area)* 100

It refers to the number of crops raised on a

field during an agricultural year.

STATE INTENSITY OF

CROPPING

Punjab 189%

Uttar Pradesh 180%

Himachal Pradesh 170%

AGRICULTURE

Haryana 168%

West Bengal 166%

Mizoram 100%

CROP SEASON MAJOR CROPS

Kharif (June-

September)

Rice, Jute, Maize,

Cotton,Bajra,

Jowar, Ragi,

Ground nut.Rabi (October-

March)

Wheat, Gram,

Rapeseeds,

Mustard, Barley,

Jowar.Zaide (April- June) Fruits, Vegetables

and fodder crops.

�

Geography

CROP REQUIREMENTS AREAS OF

PRODUCTION

RICE

India is the 2nd largest

producer and consumer.One-quarter of the net

sown area of the eastern

and western part of the

country is rice.

High heat and humidity.Temperature: 20- 30oc

Annual Rainfall: 150 cms

Soil: clayey soil.

West Bengal, Punjab,

Uttar Pradesh

WHEAT

Sown in the beginning of

winter and harvested in the

beginning of summer.India is the fourth largest

producer in the world

They’re mid-latitude

grasslands.Temperature: (10- 15)oc

Annual Rainfall: 100 cm

Soil: loamy and clayey soil.

Uttar Pradesh, Punjab

and Haryana

MAIZE

It can be used as food,

fodder and manure.

Temperature: (21- 27)o c

Annual Rainfall: (50- 100)

cm

Soil: Alluvial soil/ Red soil

Karnataka, Andhra

Pradesh, Maharashtra

MILLETS (Jowar, Ragi, Bajra, Barley)

JOWAR Temperature: (16- 30)oC

Annual Rainfall: (30-100) cm

Maharashtra, Karnataka

BAJRA Dry and warm climate

Temperature: (25- 30)oC

Annual Rainfall: (40-50) cm

Maharashtra, Gujarat

RAGI (Finger millet or Buck

Wheat)

Temperature: (20- 30)oC

Annual Rainfall: (50-100) cm

Tamil Nadu, Karnataka,

Uttarkand, Maharashtra

BARLEY It cannot tolerate high heat

and humidity

Temperature: (10-15)oC

Annual Rainfall: (75-100) cm

Uttar Pradesh, Rajasthan

�

Geography

CASH CROPS

COTTON Temperature: (21- 30)oC

Annual Rainfall: (50-100) cm

Grown in areas having

atleast 210 frost-free days.

Gujarat, Maharashtra,

Andhra Pradesh

JUTE Temperature: (24- 35)oC

Annual Rainfall: (120-

150) cm

West Bengal, Bihar, Assam

SUGARCANE

Maturing period: 10 to 15

months

India is the second largest

producer in the world.

Temperature: (21- 27)oC

Annual Rainfall: (75-150)

cm

Uttar Pradesh, Maharashtra

Tamil Nadu (long crushing

period, high yield, high

sucrose content)

TOBACCO Temperature: (16- 35)oC

Annual Rainfall: 100 cm

Andhra Pradesh, Gujarat

TEA Tropical and subtropical

plant

Hot and humid climate

Temperature: (20- 30)oC

Annual Rainfall: (150-

300) cm

Altitude: (600- 1800) m

Assam, West Bengal,

Kerala, Tamil Nadu

COFFEE Hot and humid climate

Temperature: (15- 28)oC

Annual Rainfall: (150-

250) cm

Altitude: (600- 1600) m

Karnataka, Kerala, Tamil

Nadu

RUBBER Hot and humid climate

Temperature: (25- 35)oC

Annual Rainfall: Over

200 cm

Altitude: (300- 450) m

(Not above 700 m)

Kerala, Tamil Nadu,

Karnataka, Tiripura.

••••••

�

Geography

Livestock census

Livestock census started in the

country in the year 1919. So far 18 such censuses have been conducted. The livestock census in 2012 is 19th

in the series of Livestock censuses.

The total livestock population

consisting of cattle, Buffalo, sheep,

Goat, Pig, Horses & Ponies, Mules,

Donkeys, Camels, Mithun and Yak

in the country is 512.05 million number in 2012. The total livestock population has decreased by about

3.33% over the previous census.

LIVESTOCK AND

FISHERIES

SL. No Distribution of Livestock

1. Cattle 37.28%2. Goat 26.40%3. Buffalo 21.23%4. Sheep 12.71%5. Pigs 2.01%6. Others 0.37%

SL.

No

Largest

Population

State

1. Buffalo Uttarpradesh

2. Cattle Madhya Pradesh

3. Sheep Andhra Pradesh

4. Goat Rajasthan

5. Pig Assam

6. Camel Rajasthan

�

Geography

7. Mithun Arunachal

pradesh

8. Horses Uttarpradesh

9. Mupes Uttarpradesh

10. Donkeys Rajasthan

Indian Fisheries

Indian fisheries and aquaculture is an important sector of food production,

providing nutritional security to the food

basket, contributing to the agricultural

exports and engaging 14 million people in

different activities.

1. Present fish production 6.4 mmt2. Inland fish production 3.4 mmt (55%

contribution from the inland sector)

3. Masine fish production 3.0 mmt

Fish production - Top states:

1. Gujarat 2. Maharastra 3. Karnataka 4. Kerala 5. Tamilnadu

India State of forest Report

Of the country’’s total geographical

area of 32, 87, 263 kms, 21.06 % that is 6, 92, 394 kms, is covered by forest.

Madhya Pradesh has more forests

has the maximum area under forest cover

among all the states in the country.

The report futher indicated that

Arunachal Pradesh stood next to Madhya

Pradesh, while Chhattisgarh stood at third

position.

••••••

IRCLEGeography

Page 1

POPULATION DENSITY AND DISTRIBUTION

POPULATION:

India is the second most populous country in the world after China. The first all India census, though

not taken synchronously, was completed in 1872. Since 1881, the census has been taken every decade, the

latest having been completed in 2011. According to the 2011 Census the total population of India was about

121.02 crore (1.21 billion) having registered a growth of 17.64 per cent over the 2001 figure. This total of 1.21

billion comprises about 623.7 million males and about 586.5 million females. Prersently India represents

about 17.31 per cent of the total population of the world.

POPULATION DENSITY:

Average density of population as per 2011 census is 382 persons per sq.km. the however, the density

is not uniform throughout the country. The highest density is in the NCT of Delhi – 11297 persons per sq.km.

Among the states, Bihar has the highest density – 1102 persons per sq.km. The lowest density is in Arunachal

Pradesh- 17 persons per sq.km.

One state in the country that has witnessed a negative growth in population, namely Nagaland, has

also witnessed a decline in density, from 120 persons per sq.km to 119 persons per sq.km.

SEX RATIO

The sex ratio in India is negative, i.e. there are fewer females than males in the country. The average

sex ratio according to 2011 Census is 940 females per thousand males. This figure shows a growth over the

figures for 2001 census, when the average sex ratio was 933 females per 1000 males. Kerala is the only state

with more females than males – 1084 females per 1000 males. Among Union Territories only Puducherry has

a positive sex ratio – 1038 females per 1000 males. Among states, Haryana has the lowest sex ratio – 877

females per 1000 males. The state of Tamil Nadu has the most even sex ratio among states – 995 females per

1000 males.

LITERACY:

Literacy rate is another important characteristic of population. Average rate of literacy according to

2011 Census is 74.04 per cent. Literacy is higher among males (82.14 per cent) than among female (65.91 per

cent). The highest literacy rate is among females (93.91 per cent). Kerala also has the distinction of having a

female literacy rate of more than 90 per cent. The lowest female literacy rate is in Bihar (63.82 per cent). The

lowest female literacy rate is also in Bihar (53.33 per cent). Among the Union Territories Lakshadweep has

the highest literacy rate (92.28 per cent) while Dadra and Nagar Haveli has the lowest literacy rate (77.65 per

cent) among them.

TREND OF GROWTH:

Population in India has been continuously growing since 1921 and the decade 1911-21 was the only

period of negative growth in population. The decadal growth rate showed a rising trend till 1971 when it

reached 24.80 per cent. This trend of rising growth rate has since been reversed and has come down to 17.64

per cent during 2001-11. However the growth rate in some parts of the country is still high. Dadra and Nagar

Haveli had the some parts of the country is still high. Dadra and Nagar Haveli had the highest growth rate of

55.50 per cent while Daman and Diu followed it closely with 53.54 per cent. The highest growth rate among

states has been in Meghalaya (27.82 per cent), Andhra Pradesh (25.92 per cent), Bihar (25.07 per cent),

Jammu and Kashmir (23.71 per cent), Mizoram (22.78 per cent), Chhattisgarh (25.59 per cent), Jharkhand

(22.34 per cent), Rajasthan (21. 44 per cent), Madhya Pradesh (20.30 per cent) and Uttar Pradesh (20.09

per cent). Among the larger states Kerala has the lowest growth rate (4.86 per cent). Nagaland is the only

state in the country to have shown a negative growth rate (-0.47 per cent).

TRIBAL GROUPS

SL.NO.

1. Abhors People of Mongoloid stock living in the north-easter parts of India

2. Adivasis Tribals of Bastar district, Chhattisgarh

IRCLEGeography

Page 2

3. Angami Tribals of Nagaland

4. Ao Tribals of Nagaland

5. Apatanis Tribals of Arunachal Pradesh

6. Badagas Tribals of Nilgiri region in Tamil Nadu

7. Baiga Tribals of Madhya Pradesh

8. Bakkarwals People of Jammu & Kashmir who rear sheep and goats

9. Bhils People of Davidian stock now living in central India (MP) and Rajathan

10. Bhotias Tribals of Garhwal and Kumaon regions in Uttarakhand, and Sikkim and West Bengal

11. Bhuia Tribals of MP

12. Birhors A tribal group of Madhya Pradesh, Chhattisgarh, Jharkahand and Odisha.

13. Chang Tribals found in North-East

14. Chenchus Tribals of Andhra Pradesh.

15. Chutra Tribals of Assam

16. Gaddis Tribals of Himachal Pradesh whio rear sheep

17. Gallong Tribals found in the North-East

18. Garos Hill tribe of Meghalaya and Assam

19. Gonds Tribals inhabiting forests in Madhya Pradesh, Jharkhand, Andhra Pradesh and Odisha.

20. Gujjars Animal rearers of Jammu and Kashmir and Himachal Pradesh.

21. Irula Tribnals of Tamil Nadu

22. Jaintias Hill tribe of Meghalaya and Assam.

23. Jarawas One of the oldest tribes of Andaman and Nicobar Islands inhabiting Little Andamans.

24. Kanikar Tribals found in Tamil Nadu

25. Katkari Tribals of MP

26. Kharia Tribals of MP

27. Khasa Tribals of Jaunsar Bhabar region in Uttara Khand.

28. Khasis Hill tribe of Meghalaya and Tripura.

29. Khonds Tribals inhabiting parts of Odisha

30. Kol Tribals of Madhya Pradesh and Maharashtra

31. Kolam Tribe of Andhra Pradesh

32. Kotas Tribals of Nilgiri Hills in Tamil Nadu.

33. Kuki A tribe of Maniput, Assam, Nagaland and Tripura.

34. Lahaulas Tribals inhabiting Lahaul region in Himachal Pradesh.

35. Lepchas Original tribal inhabitants of Sikkim.

36. Lushai Tribals of Mizoram and Tripura

37. Murias Tribals of Bastar district of Chhattisgarh.

38. Mikirs A tribe group of Assam.

39. Mompa Tribal found in the North-East

40. Moplahs Muslims of the Malabar district in Kerala.

41. Munda A tribe of Jharkhand, West Bengal, Odisha, Tripura and Chhattisgarh.

42. Nagas Tribals of Nagaland

43. Nishi Tribals of Nagaland.

44. Oraon Tribals inhabiting parts of Jharkhand, Chhattisgarh, Odisha and West Bengal.

45. Onges One of the tribes of Andaman and Nicobar Islands.

46. Pho Tribals of the North-East.

47. Rengma Tribals of the North-East.

48. Sabra Tribals of MP

IRCLEGeography

Page 3

49. Sangtam Tribals of the North-East.

50. Santhals Tribals living in West Bengal, Jharkhand and Odisha.

51. Sema Tribals found in Nagaland

52. Sentinelese One of the short statured tribes of Andaman and Nicobar Islands.

53. Shompens Another tribal group of Andaman and Nicobar Islands.

54. Todas Tribals of the Nilgiri Hills.

55. Uralis Tribals inhabiting parts of Kerala

56. Varlis Tribals of Maharashtra, Gujarat and Dadra & Nagar Haveli.

57. Wancho Tribals found in the North-East

58. Yurva Tribals found in Tamil Nadu

TAMILNADU POPULATION

Tamilndu is the 11th largest state in terms of area. The state is the sseventh most populous state in the

country. Population of Tamilnadu according to 2011 census stands at about 72 million.

Sex ratio - 995 Tamilnadu Urban Frame 2011

Density 1 km2 - 555 Corporation - 1

Literacy - 80.09% Municipalities - 148

Male Literacy - 86.77% Cantonment Board - 2

Female Literacy - 73.44% Town Panchayats - 561

Districts - 32 Census Towns - 376

Taluks - 215

Towns - 1097

Villages - 15243

Block - 385

Village Panchayats - 12620

Ranking of Districts of Population Size LOWEST

1. Chennai 1. Karu

2. Kancheepuram 2. Ariyalur

3. Vellore 3. Nilgiris

4. Thiruvallur 4. Perambalur

5. Salem

Ranking of Districts of Sex - ratio LOWEST

1. Nilgiris - 1041 1. Dharmapuri - 946

2. Thanjavur - 1031 2. Salem - 954

3. Nagapatinam - 1025

4. Thoothukkudi - 1024

5. Tirunelveli - 1024

LARGEST DISTRICT HIGHEST LITERACY LOWEST LITERACY

1. Viluppuram 1. Kanniya Kumari 1. Krishnagiri

2. Tirunelveli 2. Chennai 2. Viluppuram

3. Tiruvanmalai 3. Thoothukkudi 3. Ariyalur

4. Vellore 4. Nilgiri 4. Dharmapuri

5. Dindigul 5. Kancheepuram

Child Sex Ratio = 946

IRCLEGeography

Page 1

POPULATION DENSITY AND DISTRIBUTION

POPULATION:

India is the second most populous country in the world after China. The first all India census, though

not taken synchronously, was completed in 1872. Since 1881, the census has been taken every decade, the

latest having been completed in 2011. According to the 2011 Census the total population of India was about

121.02 crore (1.21 billion) having registered a growth of 17.64 per cent over the 2001 figure. This total of 1.21

billion comprises about 623.7 million males and about 586.5 million females. Prersently India represents

about 17.31 per cent of the total population of the world.

POPULATION DENSITY:

Average density of population as per 2011 census is 382 persons per sq.km. the however, the density

is not uniform throughout the country. The highest density is in the NCT of Delhi – 11297 persons per sq.km.

Among the states, Bihar has the highest density – 1102 persons per sq.km. The lowest density is in Arunachal

Pradesh- 17 persons per sq.km.

One state in the country that has witnessed a negative growth in population, namely Nagaland, has

also witnessed a decline in density, from 120 persons per sq.km to 119 persons per sq.km.

SEX RATIO

The sex ratio in India is negative, i.e. there are fewer females than males in the country. The average

sex ratio according to 2011 Census is 940 females per thousand males. This figure shows a growth over the

figures for 2001 census, when the average sex ratio was 933 females per 1000 males. Kerala is the only state

with more females than males – 1084 females per 1000 males. Among Union Territories only Puducherry has

a positive sex ratio – 1038 females per 1000 males. Among states, Haryana has the lowest sex ratio – 877

females per 1000 males. The state of Tamil Nadu has the most even sex ratio among states – 995 females per

1000 males.

LITERACY:

Literacy rate is another important characteristic of population. Average rate of literacy according to

2011 Census is 74.04 per cent. Literacy is higher among males (82.14 per cent) than among female (65.91 per

cent). The highest literacy rate is among females (93.91 per cent). Kerala also has the distinction of having a

female literacy rate of more than 90 per cent. The lowest female literacy rate is in Bihar (63.82 per cent). The

lowest female literacy rate is also in Bihar (53.33 per cent). Among the Union Territories Lakshadweep has

the highest literacy rate (92.28 per cent) while Dadra and Nagar Haveli has the lowest literacy rate (77.65 per

cent) among them.

TREND OF GROWTH:

Population in India has been continuously growing since 1921 and the decade 1911-21 was the only

period of negative growth in population. The decadal growth rate showed a rising trend till 1971 when it

reached 24.80 per cent. This trend of rising growth rate has since been reversed and has come down to 17.64

per cent during 2001-11. However the growth rate in some parts of the country is still high. Dadra and Nagar

Haveli had the some parts of the country is still high. Dadra and Nagar Haveli had the highest growth rate of

55.50 per cent while Daman and Diu followed it closely with 53.54 per cent. The highest growth rate among

states has been in Meghalaya (27.82 per cent), Andhra Pradesh (25.92 per cent), Bihar (25.07 per cent),

Jammu and Kashmir (23.71 per cent), Mizoram (22.78 per cent), Chhattisgarh (25.59 per cent), Jharkhand

(22.34 per cent), Rajasthan (21. 44 per cent), Madhya Pradesh (20.30 per cent) and Uttar Pradesh (20.09

per cent). Among the larger states Kerala has the lowest growth rate (4.86 per cent). Nagaland is the only

state in the country to have shown a negative growth rate (-0.47 per cent).

TRIBAL GROUPS

SL.NO.

1. Abhors People of Mongoloid stock living in the north-easter parts of India

2. Adivasis Tribals of Bastar district, Chhattisgarh

IRCLEGeography

Page 2

3. Angami Tribals of Nagaland

4. Ao Tribals of Nagaland

5. Apatanis Tribals of Arunachal Pradesh

6. Badagas Tribals of Nilgiri region in Tamil Nadu

7. Baiga Tribals of Madhya Pradesh

8. Bakkarwals People of Jammu & Kashmir who rear sheep and goats

9. Bhils People of Davidian stock now living in central India (MP) and Rajathan

10. Bhotias Tribals of Garhwal and Kumaon regions in Uttarakhand, and Sikkim and West Bengal

11. Bhuia Tribals of MP

12. Birhors A tribal group of Madhya Pradesh, Chhattisgarh, Jharkahand and Odisha.

13. Chang Tribals found in North-East

14. Chenchus Tribals of Andhra Pradesh.

15. Chutra Tribals of Assam

16. Gaddis Tribals of Himachal Pradesh whio rear sheep

17. Gallong Tribals found in the North-East

18. Garos Hill tribe of Meghalaya and Assam

19. Gonds Tribals inhabiting forests in Madhya Pradesh, Jharkhand, Andhra Pradesh and Odisha.

20. Gujjars Animal rearers of Jammu and Kashmir and Himachal Pradesh.

21. Irula Tribnals of Tamil Nadu

22. Jaintias Hill tribe of Meghalaya and Assam.

23. Jarawas One of the oldest tribes of Andaman and Nicobar Islands inhabiting Little Andamans.

24. Kanikar Tribals found in Tamil Nadu

25. Katkari Tribals of MP

26. Kharia Tribals of MP

27. Khasa Tribals of Jaunsar Bhabar region in Uttara Khand.

28. Khasis Hill tribe of Meghalaya and Tripura.

29. Khonds Tribals inhabiting parts of Odisha

30. Kol Tribals of Madhya Pradesh and Maharashtra

31. Kolam Tribe of Andhra Pradesh

32. Kotas Tribals of Nilgiri Hills in Tamil Nadu.

33. Kuki A tribe of Maniput, Assam, Nagaland and Tripura.

34. Lahaulas Tribals inhabiting Lahaul region in Himachal Pradesh.

35. Lepchas Original tribal inhabitants of Sikkim.

36. Lushai Tribals of Mizoram and Tripura

37. Murias Tribals of Bastar district of Chhattisgarh.

38. Mikirs A tribe group of Assam.

39. Mompa Tribal found in the North-East

40. Moplahs Muslims of the Malabar district in Kerala.

41. Munda A tribe of Jharkhand, West Bengal, Odisha, Tripura and Chhattisgarh.

42. Nagas Tribals of Nagaland

43. Nishi Tribals of Nagaland.

44. Oraon Tribals inhabiting parts of Jharkhand, Chhattisgarh, Odisha and West Bengal.

45. Onges One of the tribes of Andaman and Nicobar Islands.

46. Pho Tribals of the North-East.

47. Rengma Tribals of the North-East.

48. Sabra Tribals of MP

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49. Sangtam Tribals of the North-East.

50. Santhals Tribals living in West Bengal, Jharkhand and Odisha.

51. Sema Tribals found in Nagaland

52. Sentinelese One of the short statured tribes of Andaman and Nicobar Islands.

53. Shompens Another tribal group of Andaman and Nicobar Islands.

54. Todas Tribals of the Nilgiri Hills.

55. Uralis Tribals inhabiting parts of Kerala

56. Varlis Tribals of Maharashtra, Gujarat and Dadra & Nagar Haveli.

57. Wancho Tribals found in the North-East

58. Yurva Tribals found in Tamil Nadu

TAMILNADU POPULATION

Tamilndu is the 11th largest state in terms of area. The state is the sseventh most populous state in the

country. Population of Tamilnadu according to 2011 census stands at about 72 million.

Sex ratio - 995 Tamilnadu Urban Frame 2011

Density 1 km2 - 555 Corporation - 1

Literacy - 80.09% Municipalities - 148

Male Literacy - 86.77% Cantonment Board - 2

Female Literacy - 73.44% Town Panchayats - 561

Districts - 32 Census Towns - 376

Taluks - 215

Towns - 1097

Villages - 15243

Block - 385

Village Panchayats - 12620

Ranking of Districts of Population Size LOWEST

1. Chennai 1. Karu

2. Kancheepuram 2. Ariyalur

3. Vellore 3. Nilgiris

4. Thiruvallur 4. Perambalur

5. Salem

Ranking of Districts of Sex - ratio LOWEST

1. Nilgiris - 1041 1. Dharmapuri - 946

2. Thanjavur - 1031 2. Salem - 954

3. Nagapatinam - 1025

4. Thoothukkudi - 1024

5. Tirunelveli - 1024

LARGEST DISTRICT HIGHEST LITERACY LOWEST LITERACY

1. Viluppuram 1. Kanniya Kumari 1. Krishnagiri

2. Tirunelveli 2. Chennai 2. Viluppuram

3. Tiruvanmalai 3. Thoothukkudi 3. Ariyalur

4. Vellore 4. Nilgiri 4. Dharmapuri

5. Dindigul 5. Kancheepuram

Child Sex Ratio = 946

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DISASTER MANAGEMENT

INTRODUCTION

Disaster - What does it mean?

An unexpected event that kills a lot of people or animals and causes a lot of damage may be called as a

disaster. The term DISASTER has been derived from DISASTRE - a French word, which means ‘an evil star’. In general, a disaster is a set of terrible and unexpected events that occur due to natural or human-induced

reasons and cause severe losses to life, property and environment up to such an extent that the affected

society becomes unable to cope up with its own resources.

Components of a Disaster

A Disaster has two components:Vulnerability and Hazard. When the vulnerability meets a hazard,

the Disaster is bound to occur.

The extent to which anything is likely to be damaged or disputed by the impact of a particular hazard is

called as vulnerability.

Any dangerous condition or event that threatens or has the potential for causing damage to life,

property or environment is called as hazard. Both the vulnerability and hazard together cause a disaster.

The measure of the expected losses (like deaths, injuries, property losses etc) that are caused by a

hazard of some particular magnitude over any specific time in a given area is called as risk.

Causes of Vulnerability:

There are three major causes of vulnerability

1. Underlying causes

2. Dynamic pressure

3. Unsafe conditions.

The dynamic causes include limited access to resources, illness and disability, age and sex and poverty

etc. the Dynamic pressure include - lack of institution, education and training, skills; expansion of

population, urbanization, uncontrolled developments and environmental degradation etc. the Unsafe

conditions may be - earthquake, tsunami, floods, cyclones, volcanic eruptions, droughts, landslides, war,

technological accidents and environmental pollutions etc.

Classification of Disasters

Natural Disasters:

Disasters that occur due to abrupt changes in the earth systems and weather conditions are called as

natural disasters. These disasters have further been classified into - Planetary and Extra-Planetary Disasters.

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Planetary Disasters: Disasters that occur on land and in atmosphere due to changes in earth systems or

the geological conditions and atmosphere are called as Planetary Disasters. These disasters have further been

classified into - Terrestrial and Atmospheric disasters.

Disasters that remain confined to land and bottoms of oceans are called as terrestrial disasters.

Volcanic eruptions, earthquakes, tsunamis, landslides and mine disasters are some examples of terrestrial

disasters. Atmospheric disasters are caused due to atmospheric events. Tropical cyclones, droughts, floods

etc, are some examples of atmospheric disasters.

Extra-Planetary Disasters: Disasters occurring due to collisions between the earth and space bodies or

due to physical forces between them are called as extra-planetary disasters. High tide waves, hurricanes,

landslides, movements of rocks, changes in sea level, biological extinctions etc, are examples of extra-

planetary disasters.

Man-made Disasters

There can be disasters due to deliberate actions of individuals, groups or governments. For example, a

small group of terrorists may blow up a train or a building with explosives. Man-made disasters can also be in

the form of road, rail or air accidents.

Other causes can be:

Weapons of mass destruction

Misuse of nuclear weapons

Release of deadly germs (biological disasters)

Misuse of dangerous chemicals

Major fires due to human negligence

Collapse of tall buildings, bridges, etc.

Man- made disasters can cause great sufferings foe human beings due to loss of life and property, long-

term damage to national economy, etc.

Weapons of Mass Destruction

The weapons of mass destruction (WMD) include those articles which can cause nuclear, chemical or

biological warfare. They can cause large-scale human sufferings, loss of life and property and several other

damages.

Nuclear Weapons

Several countries in the world have developed nuclear weapons, which can be harmful and destructive.

There is a constant risk of accidental exposure to radiation from nuclear

reactors, used for the generation of electricity. Some of the most frightening

disasters have been nuclear accidents.

Precautionary measures

Do not panic, if there is a nuclear attack or a nuclear accident.

The common indicators of radioactivity are dizziness, nausea, vomiting, etc. it has no smell, but you

feel a wave of heat.

In India we celebrate the National Day

for Disaster Reduction on 29 October

every year. The main aim is to create

awareness among the people of India.

The atom bom dropped by USA on Japan during the Second World War.

On6th August 1945, the American bomber Enola Gay dropped an 8900 -

pound atomic bom (Little Boy) over the city of Hiroshima in Japan. There

was total destruction in which about 66,000 people were killed and about

69,000 injured.

On 9th August 1945, another Americanbomber dropped a bigger

bomb (Fat - Man) over the city of Nagasaki in Japan killing 39,000

persons and injured about 25,000 persons.

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A nuclear explosion is followed by a blast. If viewed,

it can cause instant blindness.

Stay indoors and close the doors and windows of

your house, as the radiation cannot penetrate solid

structures.

Chemical Disasters

The chemical disasters are caused by industrial

accidents, irresponsible handling of chemicals or by

deliberate misuse of chemicals for destructive purposes.

The leakage of poisonous gases can cause wide spread

devastation. The gases spread quickly and affect large

areas.

The material needed in the making of chemical

weapons of mass destruction (WMD) is easily available in

the markets. The manufacturing technique is also very

simple. It is difficult to detect such weapons, as the

chemical weapons of mass destruction are colourless and odourless.

Precautionary measures

Check whether the industrial units close to your city use any hazardous chemicals or not.

Find out the emergency plan to deal with such industrial accidents.

Find out the availability of the antidotes needed in case of poisoning of people, animals, water

resources, etc.

Find out from the hospitals in your city, if they are capable of handling cases of chemical disaster.

Keep a chart of Dos and Don’ts for chemical disasters. This information is either gathered from or

supplied by the industrial units.

Biological Disasters

The biological weapons of mass destruction are called the “poor man’s nuclear bomb”. The biological weapons can be made and used easily. These weapons have the potential to kill or injure lakhs of people.

In comparison to other weapons of mass destruction, the biological weapons can work instantly, but the

symptoms may not become visible initially. Sometimes it is difficult to diagnose the cause of sickness, as the

biological agents or germs take time to manifest. The biological weapons can infect even the attending

medical and para-medical staff.

A biological attack means the release of germs or other biological substances. The biological substance

can enter the body through inhalation, cuts in the skin and the food and make one sick.

Precautionary measures

A biological attack may not be known in advance. It’ll be learnt through an announcement on the radio or TV.

If we are aware of any unknown substance nearby, we must protect

our self first.

Inform others and public authorities about the possibility of any

such substance.

Move away immediately from the place, where the unknown substance is sighted.

Cover your mouth and nose with some cloth that can permit easy breathing.

The Bhopal Gas Tragedy on 3rd

December 1984, has no parallel in the

industrial accidents in the world. About 40

tonnes of Methyl Isocyanate (MIC) gas

leaked from the Union Carbide plant in

Bhopal (Madhya Pradesh). About 3000

people died and about 3,00,000 people

suffered from the disastrous effects of

massive gas poisoning.

When thousands of people reached

hospitals after the Bhopal tragedy in 1984,

most of them were breathless and blind.

The doctors did not know how to treat

them. The emergency antidotes were

neither known nor available.

It is estimated that about

100 gm of anthrax, if

released over a big

metropolitan city, can kill

about 30,00,000 people.

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Accidental Disasters

Of all the disasters, caused by human error, the most costly in terms of loss of life and property have

been accidents of transportation vehicles. Every year a large number of people die in our country due to road

and rail accidents due to human error.

Precautionary measures

Follow traffic rules to avoid road accidents.

Organise Traffic Safety Weeks to learn about traffic rules.

Inform the Police Station or Fire Station immediately after any road, rail or fire accidents.

Find out from the Fire Station about the Dos and Don’ts in case of a fire outbreak. Help the government agencies in such accidental situations.

Disaster Risk Reduction can take place in the following ways:

1. Preparedness

This protective process embraces measures which enable governments, communities and individuals to

respond rapidly to disaster situations to cope with them effectively. Preparedness includes the formulation of

viable emergency plans, the development of warning systems, the maintenance of inventories and the

training of personnel. It may also embrace search and rescue measures as well as evacuation plans for areas

that may be at risk from a recurring disaster. Preparedness therefore encompasses those measures taken

before a disaster event which are aimed at minimising loss of life, disruption of critical services, and damage

when the disaster occurs.

2. Mitigation

Mitigation embraces measures taken to reduce both the effect of the hazard and the vulnerable

conditions to it in order to reduce the scale of a future disaster. Therefore mitigation activities can be focused

on the hazard itself or the elements exposed to the threat. Examples of mitigation measures which are hazard

specific include water management in drought prone areas, relocating people away from the hazard prone

areas and by strengthening structures to reduce damage when a hazard occurs. In addition to these physical

measures, mitigation should also aim at reducing the economic and social vulnerabilities of potential

disasters.

Disaster Management and Mitigation Strategies

In general sense of the word, the act or skill of dealing with people or situation in a successful way is

called as management. In case of a disaster, formulation of strategies, taking actions and adopting processes

Well Known Maritime Disaster:

The most well known shipwreck took place on the night of 14th April 1912, when the British liner Titanic hit an

iceberg in the North Atlantic Ocean. The ‘unsinkable’ ship went down in less than three hours and 1500 out of its 2200 passengers and crew died.

The Space Shuttle Columbia disaster occurred on

February 1, 2003, when, shortly before it was scheduled to

conclude its 28th mission, STS-107, the Space Shuttle

Columbia disintegrated over Texas and Louisiana as it re-

entered Earth's atmosphere, killing all seven crew

members.

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to prevent, minimize or control the adverse impacts of a disaster at all the stages (before and after) of its

occurrence, is called as disaster management.

According to National Disaster Management Division, Ministry of Home Affairs, Government of India.

“disaster management can be defined as the body of policy and administrative decisions and

operational activities which pertain to the various stages of a disaster at all levels”.

Policies and measures designed and adopted to minimize impacts of a disaster, whether natural or

man-induced, is called as disaster mitigation. For a successful mitigation of a disaster, it is important for the

people to understand causes, seriousness, impacts and need of relief measures. Mitigation relates to the

reduction of the effects of hazards and conditions vulnerable to it. Hence, mitigation activities are focused on

both the hazard and elements exposed to the threats of the hazard concerned. The mitigation strategies are so

devised that they can modify the occurrence of a particular hazard. Here is an example- the proper

management of water, reduction of impacts and strengthening of the structures so as to reduce damage, can

be the mitigation strategies for a drought prone area. Mitigation also relates to physical, economic and social

vulnerability to a particular hazard and under lying causes of the vulnerability.

Strategies for the Management and Mitigation of Disasters

The disaster management strategies can be divided into three parts

Pre- Disaster Management Strategies or Preparedness

Disaster Occurrence Management Strategies

Post Disaster Management Strategies

Pre- Disaster Management Strategies or Preparedness

We can neither prevent nor avoid a disaster. However, we can reduce the extent of a disaster by making

advanced preparations. This incorporates four components – Awareness, Planning, Monitoring and

Development of Early Warning Systems. In fact, preparedness is a protective process. It includes such

measures which enables governments, communities and individuals to respond rapidly to the disaster

situations so as to cope with them effectively.

Awareness: Making people aware of vulnerability, hazard and extent of risk of a hazard can enable them to

protect themselves and their properties up to considerable extent. This can be done by either of the following

measures – information, education and communication (IEC). Disaster awareness help the people in

following ways –

i. It will ensure unity, co-operation and participation to fight against a particular disaster. This is due to

awareness that people may remain ready to co-operate to agencies that come forward to help them.

ii. Through awareness, people become able to protect themselves on their own against a disaster.

iii. Disaster awareness develops a sense of service among people and they remain ready to help their

fellow citizens caught in the hazard.

iv. This enables people to know legal aspects of disaster control, management and mitigation.

Planning: It is the most important component of disaster preparedness. Planning is necessary for getting

success in every sphere of life. As for a disaster, vulnerability, extent of risk, preventive measures, safety

measures, recovery options etc. are planned in advance so as to avert disaster risk carry on rescue operations.

Monitoring: Proper care and knowledge of changing conditions and operations done during Awareness

building and planning is necessary. All programmes and plans under preparations need to be monitored

carefully so as to avoid any possible mistake.

Early Warning System: Early Warning Systems are developed in disaster-prone areas to inform public to

take up necessary actions soon after a hazard is suspected. For this, warning stations are established near sea

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coasts, river banks, in industries etc. warning related to abrupt weather fluctuations are regularly transmitted

to people through communication channels. India has established various disaster warning stations in

different parts of the country. As much as 250 cyclone-warning Dissemination centres have been established

along the eastern and western sea-coasts that send early warning through communication satellites. In

modern times, remote sensing satellites are effectively employed for monitoring as well as sending data and

photographs of weather conditions. Special automatic aircrafts are also being employed for collecting

information about the changing weather.

Preparedness also includes maintenance of inventories, training of personnel, search and rescue

measures and evacuation plans. The preparedness planning needs to be supported by appropriate legislation

with clear allocation of responsibilities and budgetary provisions.

Disaster Occurrence Management Strategies

At the time when a hazard strikes, the service groups, government agencies or social organizations

should take up all possible rescue measures to protect people and their properties. At that time, activities are

taken to ensure that needs and provisions of victims are met properly and their suffering is minimized. These

strategies are called as Emergency Response Strategies.

Post Disaster Management Strategies

These strategies include – Damage Assessment, Relief Measurement and Rehabilitation. Strategies

adopted at this stage are called as Response and Recovery Strategies. Under these strategies, activities are

taken to achieve early recovery and removal of earlier vulnerable conditions. An assessment of damage is

done through surveys and baseline data collection etc. the relief and Rehabilitation measures are done on the

basis of these activities. Other activities covered under these strategies are

Empowerment of women,

Coping with post disaster situations, restoration of livelihood with overall purpose of sustainable

environment, and

A coherent mechanism should be designed for meeting the needs of children following disasters. The

rehabilitation of children should be priority, but in some cases their future outside the village might

be preferable.

Management and Mitigation of Disasters

Management and Mitigation of Natural Disasters

EARTHQUAKES

Sudden release of stresses built up in the earth’s crust shaking of the earth surface. It is called as earthquake. The intensity of an earthquake is measured on Richter Scale, which was devised in 1935 by

Charles Richter of California Institute of Technology, U.S.A. an earthquake measuring more than 5 on

Richter Scale (usually 7 and above ) causes great damage. The place of origin of an earthquake is called as its

focus or the hypocentre where as the point on the earth surface vertically above the Focus is called as

Epicentre. Earthquakes cause physical, biological, economic and environmental damages.

Management and Mitigation (Control Measures)

These strategies comprise main and community based activities mentioned below –

Contractors and developers of building constructions must follow norms fixed for buildings. Building

constructions should be done on soft soils.

Buildings should not be constructed in vulnerable areas and those that have already been built in such

areas should be strengthened properly.

Use of standard quality building materials and following Indian Standard Codes for building

constructions should be kept on priority.

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Human habitations at high risk zones should be shifted elsewhere.

People should be made aware of dos and don’ts about earthquakes and important lifeline buildings should be strengthened to accommodate people after the earthquake. Hospitals and fire services

should be upgraded.

Community should be prepared and educated for mitigating impacts of earthquakes.

Community based Earthquake Risk Management Projects should be developed. Retrofitting of school

buildings and other important buildings purchased of Emergency Response Equipment etc., should

be the principal activities of such projects.

CYCLONES

Cyclones are extremely disastrous hazards that originate in seawater. These are usually followed by

wind of very high speed. These are atmospheric disasters occurring in tropical and coastal regions in

Bangladesh and India. Cyclones of eastern U.S.A. and Caribbean region are called as hurricanes and the same

in the North Pacific Oceans are called typhoons. Local storms are called tornados. Cyclones usually extend

vertically up to 12 – 14 km and horizontally up to 150 – 1000 km.

Management and Mitigation:

Disasters due to cyclones can be prevented by adopting safety measures and by constructing barriers.

Some important measures for mitigation of cyclones are mentioned below.

Wide buffer zones of forests should be managed properly along the coastal line so that cyclone may not

run freely to penetrate inland.

Meteorological records of wind speed and directions should be kept properly so as to predict for

future cyclones and to make advanced preparations. In this regard horizontal mapping is very

important.

Policies should be made to regulate land use and enforcement of building codes. Vulnerable areas

should be reserved for parks, grazing grounds or play grounds.

Buildings in coastal areas should have high engineering inputs. Traditional homes should be

improved by building in disaster resistant features so that they can withstand cyclones with moderate

speed.

Building meant for storing food supply should be protected against winds and water.

Arrangement of early warning systems, construction of concrete walls along coast line, organization of

action groups and rescue squads etc. are some other important measures to mitigate cyclones.

Environmental facts

There is an ocean current that flows along the Peruvian Coast. It is called as Humboldt Current, after

the Prussian Explorer Alexander von Humboldt. This ocean current serves as a classical example of an

eastern boundary current and features a typically wide and slow equator ward transport of cold water along

the coast of South America.

The Peruvian current is the largest upwelling system among the eastern boundary currents. Upwelling

is a process in which cold-nutrient rich water rises to the surface from the ocean depths.

The North-western alignment of the Andes Mountain along the Peruvian Coast forces the south-east

trade winds to blow northwards. This condition causes an offshore flow in the surface layers of the marine

water. This makes it one of the most productive upwelling systems in the world causing the cold nutrient

water to appear along the coast. It supports an extra-ordinary abundance of marine life. The Peruvian ocean

current system accounts for approximately 18 to 20 percent of the tidal fish catch worldwide. The weakening

of the Peruvian current system allows the counter current to move southwards. It disrupts the coastal

upwelling which normally occurs along the coast and creating a condition known as El-Nino. El-Nino is the

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warming of sea surface temperatureeratures in the equatorial Pacific Ocean which influences atmospheric

circulation and consequently rainfall and temperatureerature in specific areas around the world.

El-Nino is a Spanish word which means Christ Child. It indicates the appearance of a warm ocean

current of the South American Coast around the Christmas. Approximately 14 El-Nino events affected the

world between 1950 and 2003. On the reverse side, is La-Nina which is the cooling of sea surface

temperatureerature in the equatorial Pacific Ocean, and which influences the atmospheric circulation, and

consequently the rainfall and temperatureerature in specific areas around the world. It is the opposite of El-

Nino.

DROUGHTS

Failure of rains cause prolonged periods of dryness which results into crop-failures. This condition is

called as drought. Drought causes deaths of human and cattle as they cannot withstand dry weather. Drought

enforces many populations to mitigate elsewhere which creates further problems of rehabilitation.

Management and Mitigation

Drought can be managed and mitigated in following ways –

Management of watersheds, water-harvesting structures and other measures should be undertaken to

ensure water supplies in the area.

Drought resisting crops or crops demanding less water should be cultivated in drought prone areas to

ensure food supply.

Afforestation and other forestry measures should be undertaken so as to retain humidity in the

atmosphere and promote precipitation.

Cutting of trees and clearing of forests should be banned.

Roof top water harvesting in house should be adopted in every house so as to retain water for

different uses.

LAND SLIDES

The downhill movement of large amounts of soil, mud, rocks, debris is called as landslide. It causes

flooding of rivers due to deposit of silt and aggravates floods. Landslides cause maximum fatalities depending

on the place and time of occurrence. Landslides may kill many thousands of people. The landslide in Peru in

1970 killed 18000 people.

Management and Mitigation

The Management and Mitigation of disasters due to landslides can be done by adopting following measures.

Clearing of forests on hill slopes must be stopped.

Proper monitoring and warning systems should be developed in landslide prone areas so as to

facilitate the activities of evacuation before the disaster.

Search and rescue operations should be done by special rescue squads.

The assessment of damage, financial assistance to the affected people and rehabilitation should be

done in time.

Retaining walls should be built to stop land from slipping.

The surface drainage control works should be implemented to control the movement of soil

accompanied by infiltration of rain water and spring flows.

Increasing vegetation cover, building engineering structures and insurance of people are other

measures to mitigate the disasters due to landslides.

TSUNAMIS

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Tsunamis are towering walls of marine water having great powers of destruction. These are usually

caused due to undersea earthquakes or undersea “volcanic eruptions. Tsunami is a Japanese word which

means harbour waves. These may also be caused by undersea landslides and force of an asteroid crashing

into ocean.

Management and Mitigation

The management and mitigation of tsunami hazards need specific preparedness measures like

Hazard mapping, arrangement of early warning systems and community participation. Main tsunami

mitigation strategies should include site planning, land management and evacuation of public living

in coastal areas.

Residents of coastal areas should shift their houses far beyond the coast line and they should

construct houses on high ground levels.

Water breakers should be constructed to reduce the reduce the velocity of waves. For construction,

water resistant and corrosion resistant materials should be used.

Community halls should be constructed at higher locations that may act as shelters during the

disasters.

Sea walls should be constructed to stop the gushing water.

FLOODS

Floods cause great losses to life and property every year. Occurrence of floods is a cumulative condition

which appears as accumulation of huge volumes of water in a vast area.

Management and Mitigation

Following are the measures usually adopted for the management of disasters due to floods

Arrangement of proper warning systems to relocate people,

Construction of embankments to restrict water against entering into human habitations,

Ban on cutting trees on hill slopes and on other areas as well and checking soil erosion so as to avoid

the Siltation of rivers,

Proper rescue and relief operations,

Mass scale tree plantation in flood prone areas.

Management and Mitigation of Man-made Disasters

Man-made disasters can be managed and mitigated through following general measures

The spread of epidemics can be managed by keeping healthy living conditions, proper storage of food

materials, proper storage of water, proper disposal of wastes, checking pollutions of resources at all

levels,

Nuclear hazards can be prevented by proper handling and disposal of nuclear wastes,

Traffic accidents can be avoided by obeying traffic rules,

Biological, chemical and industrial disasters can be prevented by strict legislations, increasing moral

values in societies, upgrading medical facilities, building up public awareness, proper education etc.

GOVERNMENT’S ROLE IN DISASTER MANAGEMENT AND MITIGATION

Though the institutional and policy mechanisms for carrying out response, relief and rehabilitation

have been established in India. Since Independence, the Ministry of Home affairs. (The Government of India)

created a National Disaster Management Division (NDM) on June 2002 and restructured various Disaster

Management committees on state District and Block levels.

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1. The central government has taken up various step to strengthen management a and mitigation

instruments in the country. In case of major disasters, the Central Government is inclined to provide

financial and organizations. The apex body is the cabinet committee on national calamities (NCMC)

2. The NCMC gives directions to the crisis management Groups. The chairman of the crisis management

group is the central relief commissioner, Ministry of Home Affairs. This group reviews contingency

plans formulated by various ministries, departments of organizations and measures required for

dealing with a natural disaster and co-ordinates functions of Central Ministries and State

Governments in relation to disaster preparedness and relief.

3. The government of India has proposed the organization of National Emergency Management

Authority on the national and state levels. States have been directed to set up Disaster Management

Authorities under the Chief Minister with Ministers of different departments as members.

4. The Central Government has directed state governments to reorganize the Department of Disaster

Management and to form four functional groups and to assign those four functional groups their

functions below

Hazard Mitigation - Functional Group One

Preparedness and Capacity Building - Functional Group Two

Relief and Response - Functional Group Three

Administration and Finance - Functional Group Four

5. At district level the District Magistrate is the Chief Co-ordinator of all those activities related to

prevention, mitigation and preparedness. The District Committee is reconstituted as Disaster

Management Committee and Disaster Management Teams are to be constituted to work under it.

6. Different institutes have been established I different parts of India to impart training for the

development of skilled citizens for a better management and mitigation of disasters. Names of some

important institutes are mentioned below.

Centre for Disaster Management, Mussoorie,

National Institute of Disaster management, New Delhi

National Fire Service College, Nagpur,

CHERNOBYL DISASTER

The Chernobyl nuclear power plant in the Ukraine exploded on April 26; 1986. The effects of the

explosion was felt for thousands of kilometres. The plant is located 14.5 km northwest of Chernobyl. A

number of things caused the disaster at Chernobyl. First, the plant was not properly designed, and could only

be run with very specific instructions. Second, the operators of the plant failed to properly follow instructions

and some scientists conducted a highly risky experiment that led to the explosion. The scientists decided to

conduct the experiment and had to remove safety and cooling equipment in order to do so. Eventually,

pressure on the reactor’s roof blew it away. Everything inside, including molten uranium, burning graphite and radioactive ashes were emitted into the atmosphere.

This was not a nuclear explosion. There was no chain reaction or explosion like that in an atomic bomb.

However, the amount of radioactive material released was ten times that caused by the US atomic bombing of

Hiroshima. Radioactive fallout spread throughout Europe. It hit Poland, Germany, Belgium, France and

Holland and then shifted towards the Balkans and Italy.

It is hard to predict just how many people were affected by the Chernobyl explosion. A British report

estimated that the radioactivity will give 2300 people cancer, though others think the number is much

higher. It was an important lesson for us that maximum care, skill and safety measures are essential while

working with nuclear plants and devices.

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International organizations involved in disaster management

International Association of Emergency Managers

The International Association! of Emergency Managers (IAEM) is a non-profit educational

organization dedicated to promoting the goals of saving lives and protecting properly during emergencies and

disasters. The mission of IAEM is to serve its members by providing information, networking and

professional opportunities, and to advance the emergency management profession. It currently has seven

Councils around the World: Asia, Canada, Europa, International, Oceania, Student and USA.

International Recovery Platform

The International Recovery Platform CI.RP) was conceived at the World Conference on Disaster

Reduction (WCDR) in Kobe, Hyogo, Japan in January 2005. As a thematic platform of the International

Strategy for Disaster Reduction (lSDR) system, IRP is a key pillar for the implementation of the Hyogo

Framework for Action (HF A) 2005-2015: Building the Resilience of Nations and Communities to Disasters, a

global plan for disaster risk reduction for the decade adopted by 168 governments at the WCDR.

The key role of IRP is to identify gaps and constraints experienced in post disaster recovery and to serve

as a catalyst for the development of tools, resources, and capacity for resilient recovery. IRP aims to be an

international source of knowledge on good recovery practice.

Red Cross/Red Crescent

National Reel Cross/Red Crescent societies often have pivotal roles in responding to emergencies.

Additionally,· the International Federation of Red Cross and Red Crescent Societies (If-RC, or "The

Federation") may deploy assessment teams, e.g. Field Assessment and Coordination Team - (FACT) to the

affected country if requested by the national Red Cross or Red Crescent Society. After having assessed the

needs Emergency Response Units (ERUs) may be deployed to the affected country or region. They are

specialized in the response component of the emergency management framework.

United Nations

Within the United Nations system responsibility for emergency response rests with the Resident

Coordinator within the affected country. However, in practice international response will be coordinated, if

requested by the affected country's government, by the UN Office for the Coordination of Humanitarian

Affairs (UN-OCHA), by deploying a UN Disaster Assessment and Coordination (UNDAC) team.

World Bank

Since 1980, the World Bank has approved more than 500 operations related to disaster management,

amounting to more than US$40 billion. "These include post-disaster reconstruction projects, as well as

projects with components aimed at preventing and mitigating disaster impacts in countries such as

Argentina, Bangladesh, Colombia, Haiti, India, Mexico, Turkey and Vietnam to name only a few.

Common areas of focus for prevention and mitigation projects include forest fire prevention measures,

such as early warning measures 'and education campaigns to discourage farmers' from slash and burn

agriculture that ignites forest fires; early-warning systems or hurricanes; flood prevention mechanisms,

ranging from shore protection and terracing in rural areas to adaptation of production; and earthquake-

prone construction.

In a joint venture with Columbia University under the umbrella of the Prevention Consortium the

World Bank has established a Global Risk Analysis of Natural Disaster Hotspots. in Jun: 2006, the World

Bank established the Global Facility for Disaster Reduction and Recovery (GFDRR), a longer term

partnership with other aid donors to reduce disaster losses by mainstreaming disaster "risk reduction in

development, in support of the Hyogo Framework of Action. The facility helps developing countries fund

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development projects and programs that enhance local capacities for disaster prevention and emergency

preparedness.

European Union

Since 2001, the EU adopted Community Mechanism for Civil Protection, which started to play a

significant role on the global scene. Mechanism's main role is to facilitate co-operation in civil protection

assistance interventions in the event of major emergencies which may require urgent response actions. This

applies also to situations where there may be an imminent threat of such major emergencies. The heart of the

Mechanism is the Monitoring and Information Centre. It gives countries access to a platform, to a one-stop-

shop of civil protection means available amongst the all the participating states. Any country inside or outside

the Union affected by a major disaster can make an appeal for assistance through the MIC. It acts as a

communication hub at headquarters level between participating states, the affected country and dispatched

field experts. It also provides useful and updated information on the actual status of an on going emergency.

Disaster Management Act 2005

Act provides for the effective management of disaster and - for matters connected there with of

incidental thereto. It provides institutional mechanisms for drawing up and monitoring the implementation

of the disaster management The Act also ensures measures various wings of the Government for prevention

and mitigation of disasters and prompt response to any disaster situation

The Act provides for setting up of a National Disaster Management Authority (NDMA) under the

Chairmanship of the Prime Minister, State Disaster Management Authorities (SDMAs) under the

Chairmanship of the Chief Ministers, District Disaster Management Authorities (DDMAs) under the

Chairmanship of Collectors / District Magistrates / Deputy Commissioners. The Act further provides for the

constitution of different Executive Committee at national and state levels.

Under its aegis, the National Institute of Disaster Management (NIDM) for capacity building and

National Disaster Response Force (NDRF) for response purpose have been set up. It also mandates the

concerned Ministries and Departments to draw up their own plans in accordance with the National Plan. The

Act further contains the provisions for financial mechanisms such as creation of funds for response, National

Disaster Mitigation Fund and similar funds at the state and district levels for the purpose of disaster

management. The Act also provides specific roles to local bodies in disaster management.

Further the enactment of 73rd and 74th Amendments to the constitution and emergence of local self-

government, .both rural and urban, as important tiers of governance, the role of local authorities becomes

very important. The DM Act, 2005 also envisages specific roles to be played by the local bodies in disaster

management.

Role Players : Legal Institutional Framework

Union

Government

StateGover

nment

District

Administratio

Panchaya Municipali

MHA

NID

National Disaster

Management Authority

State

Disaster

Management

District Disaster

Management

Authority

NEC

Secretaries of

all relevant

SEC

Secretaries

of all

relevant

Ministries

DMA

NDR

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National policy on disaster management 2009

This policy aims at: (i) Promoting a culture of prevention, preparedness and resilience at all levels

through knowledge, innovation and education; (ii) Encouraging mitigation measures based. on technology,

traditional wisdom and environmental sustainability; (iii) Mainstreaming disaster management into the

developmental planning process; (iv) Establishing institutional and technological frameworks to create an

enabling regulatory environment and a compliance regime; (v) Ensuring efficient mechanism for

identification, assessment and monitoring of disaster risks; (vi) Developing contemperatureorary forecasting

and early warning systems backed by responsive and fail-safe communication with information technology

support; (vii) Ensuring. efficient response and relief with a caring approach towards the needs of the

vulnerable sections of the society; (viii) Undertaking reconstruction as an opportunity to build disaster

resilient structures and habitat for ensuring safer living; and (ix) Promoting a productive and proactive

partnership with the media for disaster management.

Traditionally, relief in the wake of natural calamities has been treated as the primary responsibility of

the States. Successive Finance Commissions have also reiterated this position:· Even though the States are

primarily responsible for relief activities, the Central Government associates itself with measures aimed at

ameliorating the sufferings of the people on account of natural calamities. Towards this end, the Central

Government, with its resources, physical and financial does provide the needed help and assistance to

buttress relief efforts in the wake of major natural calamities. The dimensions of the response at the level of

National Government are determined in accordance with the existing policy of financing the relief

expenditure and keeping in view the factors like (i) the gravity of a natural calamity, (ii) the scale of the relief

operation necessary and (iii) the requirements of Central assistance for augmenting the financial resources

at the disposal of the State Government.

Types of Response:

The Central response can be:

(i) Policy response, and

(ii) Administrative response.

Policy response:

The policy response to a natural calamity would be provided by the Prime Minister, Cabinet

Committees and the Agriculture Minister. The objectives of policy response would be:

a. To empathise with the sufferings of the people affected by natural calamity, and

b. To sub-serve long term and short term policy objectives of the government.

Administrative response:

The response of the administration to a situation arising out of a natural calamity can be on account of:

i. a follow-up of a policy objective of the Government;

ii. the need or an assessment of the situation and for a central response;

iii. States' requests for central assistance; and

iv. the need for information as a governance objective.

Central response: Central Government's response, at the policy level, to a natural calamity would lead to

Central initiatives in the form of.-

i. visits of the calamity affected areas by President, Prime Minister and other dignitaries;

ii. activating the administrative machinery for assisting in relief measures; and

iii. setting up a machinery for implementing, reviewing and monitoring of relief measures.

The administrative response at the Central Government level would broadly relate to:-

i. operational requirements; and

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ii. provision of Central assistance as per existing policy.

The operational aspects of the administrative response could, further, be classified into

i.Primary relief functions, and

ii. Secondary relief functions.

The primary relief functions of the Central Government would relate to:

i. Forecasting and operation of warning system;

ii Maintenance of uninterrupted communication;

iii. Wide publicity to warnings of impending calamity, disaster preparedness and relief measures

through TV, AIR and Newspapers;

iv. Transport with particular reference to evacuation and movement of essential commodities and

petroleum products;

v. Ensuring availability of essential commodities at reasonable prices particularly the commodities

through the Public Distribution System;

vi. Ensuring availability of medicines, vaccine and drugs;

vii. Preservation and restoration of physical communication links;

viii. Investments in infrastructure; and

ix. Mobilisation of financial resources.

The secondary functions of the Central Government which supplement the States' relief efforts, would

relate to.

i. Flood/inflow forecasts from the Central Water-Commission; .

ii. Relief, rehabilitation and restoration through military aid to civic authorities;

iii. Contingency plans for crops, cattle preservation nutrition and health measures;

iv. Technical and technological inputs for provision of drinking water;

v. Technical assistance in the water budgeting and water management for various uses; and .

vi. Coordination of tile activities of the State agencies and voluntary agencies.

National Disaster Management Authority

Over the centuries, local communities have developed their 'own indigenous survival mechanisms. This

rich storehouse of knowledge is a part of our country's legacy. The Arthashastra, (a treatise on public

administration by Chanakya in the 4th century RC), devoted a section to mitigation measures to combat

famines. Modern methods of crisis management began to be applied from the late 1870s when the first

Famine Commission suggested formulation of Famine Codes and establishment of Agriculture Departments

in the provinces to improve agricultural production as a safeguard against famines as well as preparatory

measure to deal with acute scarcities occasioned by frequent failure of rains.

NDMA Policy

This Policy framework is also in conformity with the International Strategy for Disaster Reduction, the

Rio Declaration, the Millennium Development Goals and the Hyogo Framework 200S-201 S. The themes

underpinning this policy are:- (Five "C" as a memory aid)

Community-based disaster management, including last mile integration of the policy,

plans and execution.

Capacity development in all related areas.

Consolidation of past initiatives and best practices.

Cooperation with agencies at national, regional and international levels.

Compliance and coordination to generate a multi-sectoral synergy.

From the national vision and aforementioned theme, the objectives guiding the policy formulation have

evolved to include:

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Promoting a culture of prevention and preparedness - by centre-staging DM as an overriding priority

at all levels and at all times.

Encouraging mitigation measures based on state-of-the-art technology and environmental

sustainability.

Mainstreaming DM concerns into the development planning process.

Putting in place a streamlined institutional techno-legal framework in order to create and preserve the

integrity of an enabling regulatory environment and a compliance regime.

Developing contemperatureorary forecasting and early warning systems backed by responsive and

fail-safe communications and Information Technologv.

Promoting a productive partnership with the Media, NGOs and the Corporate Sector in the areas of

awareness generation and capacity development.

Ensuring efficient response and relief with a caring humane approach towards the vulnerable sections

of the society.

Making reconstruction an opportunity to build back better an construct disaster-resilient structures

and habitats.

Roles and Responsibilities

NDMA as the apex body is mandated to lay down the policies, plans and guidelines for Disaster

Management to ensure timely and effective response to disasters: Towards this it has the following

responsibilities:- .

Lay down policies on cl Disaster management

Approve the National Plan;

Approve plans prepared by the Ministries or Departments of the Government of India in accordance

with the National Plan;

Lay down guidelines to be followed by the State Authorities in drawing up the State Plan;

Lay down guidelines to be followed by the different Ministries or Department of the Government of

India for the purpose of integrating the measures for prevention of disaster or the mitigation of its

effects in their development plans and projects

Coordinate the enforcement and implementation of the policy and plan for disaster management.

Recommend provision of funds for the purpose of mitigation

Provide such support to other countries affected by major disasters as may be determined by the

Central Government

Take such other measures for the prevention of disaster, or the mitigation or preparedness and

capacity building for dealing with the threatening disaster situation or disaster as it may consider

necessary

Lay down broad policies and guidelines for the functioning of the National Institute of Disaster

Management.

Organisation

National Disaster Management Authority has been constituted with the prime Minister of India a its

Chairman, a Vice Chairman with the status of Cabinet Minister and eight members with the status of

Ministers of State.

The Concept of the organization is based on a disaster divisions – cum secretariat system. Each

member of the Authority heads disaster – specific divisions for specific disaster and functional domains.

Each member has also been given the responsibility of specified states and UTs for close interaction and

coordination

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The NDMA Secretariat headed by a Secretary is responsible to provide secretarial support and

continuity.

National Executive Committee (NEC)

National Executive Committee is constituted under section 8 of DM Act, 2005 to assist the National

Authority in the performance of its functions. NEC consists of Home Secretary as its Chairperson, ex – officio

with other secretaries to the Government of India in the Ministries of Departments having administrative

control of the agriculture, atomic energy, defence drinking water supply, environment and forest, finance

(expenditure), health, power, rural development science and technology, space, telecommunication, urban

development, water resources. The Chief of Integrated Defence Staff of the Chiefs of Staff Committee, ex

officio is also its members.

NEC may as and when it considers necessary constitute one or more sub – committees for the efficient

discharge of its functions. For the conduct of NEC, Disaster Management National Executive Committee

(Procedure and Allowances) Rules, 2006 has been issued NEC has been given the responsibility to act as the

coordinating and monitoring body for disaster management, to prepare a National Plan, monitor the

implementation of National policy etc. Vide section 10 of the DM Act.

State level Institutions

State Disaster Management Authority (SDMA)

The DM Act, 2005 provides for constitution of SDMAs and DDMAs in all the states and UTs. As per the

information received from the states and UTs except Gujarat has constituted its SDMA under its Gujarat

State Disaster Management Act, 2003 Daman & Diu have also established SDMAs prior to enactment of DM

Act 2005.

State Executive Committee (SEC)

The Act envisages establishment of State Executive Committee under Section 20 of the Act to be headed

by Chief Secretary of the state Government with four other Secretaries of such departments as the state

Government may think fit. It has the responsibility for coordinating and monitorinig the implementation of

the National policy, the National Plan and the state Plans as provided under section 22 of the Act.

District level Institutions

District Disaster Management Authority (DDMA)

Section 25 of the DM Act provides for constitution of DDMA for every district of a state. The District

Magistrate / District collector / Deputy commissioner heads the Authority as chairperson besides an elected

representative of the local authority as Co- chairperson except in the tribal areas where the chief Executive.

Further in district , where Zila parishad exist, its Chairperson shall be the Co – Chairperson of DDMA. Other

members of these authority included the CEO of the District Authority, superintendent of police, chief

Medical officer of the District and other two district level officers are designated by the state Government.

The District Authority is responsible for planning, Coordination and implementation of disaster

management and to take such measures for disaster management as provided in the guidelines. The District

Authority also has the power to examine the construction in any area in the district to enforce the safety

standards and also to arrange for relief measures and respond to the disaster at the district level.

Institutional Framework for Metropolitan Cities

In the larger cities (say, with population exceeding 2.5 million) the recommendation of the second

Administrative Reforms Commission has suggested that the Mayor assisted by the Commissioner of the

Municipal Corporation and the police Commissioner to be directly responsible for Crisis Management. It has

now been accepted by the Government.

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National Institute of Disaster Management

The National Institute of Disaster Management (NIDM) was constituted under an Act of Parliament

with a vision to play the role of premier institute for capacity development in India and the region. The efforts

in this direction that began with the formation of the National Centre for Disaster Management (NCDM) in

1995 gained impetus with its re-designation as the National Institute of Disaster Management (NIDM) for

training and capacity development. Under the Disaster Management Act 2005, NIDM has been assigned

nodal responsibilities for human resource development capacity building, training, research. Documentation

and policy advocacy in the field of disaster management.

NIDM provides technical support to the state governments through the Disaster Management Centres

(DMCs)in the Administrative Training Institutes (ATIs) of the States and Union Territories

NIDM hosts the SAARC Disaster Management Centre (SDMC) and works as its national focal point.

It’s a vision is to create a Disaster Resilient India by building the capacity at all levels for disaster prevention and preparedness

Interface among Stakeholders Leading To Development of Society

NDMA guidelines on specific disasters

Focus and objectives of Guidelines

Management of Landslide and snow Avalanches

Management of Cyclones

Management of Earthquake

Management of Floods

Chemical Disasters (Industrial)

Management of Chemical (Terrorism) Disaster

Ministry of Home Affairs (MHA)

National Disaster Management Authority (NDMA) Chair

Prime Minister with other 9 members

National Executive Committee Comprising of representative from the ministries and departments controlling agriculture, atomic enery defence, dirnikning water supply environment & forests, finance, expenditure, health power rural development S&T soace, telecommunication water resources

Advisory Committee National

Institute of

Disaster

Managem

National

Disaster

Respons

e Force

State Disaster Mangement Authority (9 member body chaired by the CM of the state)

Sate Execultive Committee Advisory Committee

District Disaster Management Authority

(7 member body charied by the District Magistrate and comprising of representatives from the civil

Local Authorities Advisory

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Preparation of State Disaster Management Plans

Psycho – Socio support and Mental Health services in Disasters

Medical Preparedness and Mass casualty Management

Management of Nuclear and Radiological Emergencies

Incident Responses System

Strengthening of Safety and Security for Transportation of tankers

Management of Biological Disaster, Management of Tsunami

Role of NGOs in Disaster Management, Urban Flooding

Management of Dead in the Aftermath of Disaster

Plan to counter threats to Municipal water supply and water Reservoirs

Disasters Agencies

Cyclone Indian Meteorological Department Tsunami Indian National Centre for Oceanic information Service Floods Central Water Commission Landslides Geological Survery of India Avalanches Snow and Avalanche Study Establishment Heat & Cold Waves Indian Meteorological Department

TOWARDS A BETTER ENVIRONMENT

The Government of India has given special emphasis on the management and mitigation of disasters in

the country. Accordingly, a number of special attemperaturets have been taken in different sectors.

A Disaster Risk Management Programme has been started with the assistance of United Nations

Development Programme. The programme covers 169 Districts of 17 hazard prone states of India. The

Government has also joined hands with a number of International agencies for co-operations in the field of

Training and Capacity Building for Disaster Management and Mitigation. Asia Disaster Reduction Centre

(ADRC) Japan, Indo-Swiss Agreement for co-operation and Asian Disaster Management Centre are some

names of such organizations.