THE NATURAL DISASTERS IN BANGLADESH

1. INTRODUCTION:Natural calamity is a natural event which has an adverse

sociological and economic impact on the whole environment. In

recent years, they have become more frequent because of the

climate change over the world. That is way; they are now being

addressed as a global problem. Bangladesh, a South Asian

Country  located next to India is prone to natural disasters

i.e. flood, cyclone, tornado etc. due to being situated on

the Ganges Delta and the many tributaries flowing into the Bay

of Bengal.1 Bangladesh, a nation is very much at risk of such

natural hazards despite its development. Such natural

disasters cause heavy damage to the lives, goods and

properties. Effective measures can play a vital role in the

mitigation of the sufferings of lives, loss of goods and

properties etc.

2. NATURAL DISASTER: CONCEPT AND MEANING:Natural disaster is a major adverse even resulting from

natural processes which could be related to weather, geology,

biology or even more factors outside the Earth. For example:

Floods 

Volcanic Eruptions

Earthquakes1 http://en.wikipedia.org/wiki/Natural_disaster. Date of access- 12/02/2014.

Tsunamis

Landslides

and for other Geological Processes

These are natural disasters which are caused by environmental

factors that injure people, damage property and leave some of

economic damage in its wake.

3. NATURAL DISASTERS IN BANGLADESH:Bangladesh, a country in Southern Asia is a home of 140

million people, is widely known as a land of natural

disasters. Every year, Bangladesh is affected by natural

disasters like, cyclones, drought, earthquake, tornado, river

bank erosion, landslide etc. Recently, tsunami also little bit

has affected our country. Natural disaster causes heavy tolls

in our country. Many people are killed and many other become

homeless. After disaster, many diseases break out and

communication system is suspended causing untold sufferings to

people.

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Figure 1: Natural

Map 1: Hazard groups in Bangladesh

3.1 FLOODS: Floods are the overflow of a

large amount of water beyond

its normal limits, especially

over what is normally dry

land. Floods are the most

significant natural hazard in

Bangladesh causing extensive damage to human life and

property. The major floods that occurred in 1954, 1955, 1974,

1984, 1987, 1988, 1993, 1998, 1999, 2000 and 2007 have been

very destructive and caused serious threat to lives and

economy. Floods hit our country during the rainy season when

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Figure 2: Floods in Bangladesh

there is excessive rainfall. The 1988 flood set a new record

for flooded area, while 1998 flood was unprecedented with its

long duration. The flood damage potential in Bangladesh is

increasing due to the possible causes of climate change, urban

concentration in the three river basins, encroaching of

settlements into flood prone areas, and over reliance on the

safety provided by flood control works such as levees,

reservoirs.2

2 http://www.saarc-sadkn.org/countries/bangladesh/hazard_profile.aspx#top. Date of access - 15/02/2014.

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Map 2: Flood Prone Areas in Bangladesh

There are two types of floods which occur in Bangladesh:

annual floods (barsha) that inundate up to 20% of the land

area; and low frequency floods of high magnitude that inundate

more than 35% of the area (bonna). In the context of human

exposure in flood hazard zones, nearly 19,279,960 people are

present in these zones and Bangladesh ranks 1st among 162

nations. Similarly, the modeled amount of GDP in seismically

hazardous zones puts Bangladesh 3rd among 162 countries. 

Year Death

1988 1708

1998 918

2004 747

2007 800

Table 1: Major Floods in Bangladesh

3.2 CYCLONE:

Cyclone is the system of winds rotating inwards to an area of

low barometric pressure, with an anticlockwise (northern

hemisphere) or clockwise (southern hemisphere) circulation.

Cyclones, sometimes associated with storm surge have been a

cause of concern for Bangladesh. From 1891–98, approximately

178 severe cyclones with wind speeds of more than 87

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kilometers per hour (km/h) formed in the Bay of Bengal,

causing extensive loss of life and destruction of property.3

From 1970–98, there was devastation due to 38 severe cyclones.

The April 1991 cyclone inflicted a material damage was about

USD 2.4 billion and human casualties numbered around 140,000.

In 1970, a similar catastrophe claimed some 500,000 lives. In

addition, storm surge, an unusual rise in seawater associated

with a tropical cyclone originating in the Bay of Bengal, has

also caused major devastation in the coastal region. 

3 http://www.saarc-sadkn.org/countries/bangladesh/hazard_profile.aspx#top. Date of access- 15.02.2014.

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Figure 3:Mahasen

In November 2007, cyclone side struck the coastal region, the

worst of its type since 1991, with winds of 250 km/h—155 miles

per hour (mph)—and a five meter sea surge, killing more than

3,300 people. Millions of people were affected, approximately

one million tonnes of rice crop was lost, and by January 2008

nearly 500,000 people were estimated still to be living in

temporary accommodation. In Bangladesh nearly 4,641,060 people

are exposed in areas under the threat of cyclones; ranking it

6th among the 89 countries analysed. 

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Map 3: Cyclone Affected Areas in Bangladesh

Date Maximum Wind

speed

(km/hr)

Storm Surge

height

(metres)

Death Toll

11 May 1965 161 3.7-7.6 19,27915

December1965 217 2.4-3.6 873

01

October1966 139 6.0-6.7 850

12

November1970 224 6.0-10.0 300,000

25 May 1985 154 3.0-4.6 11,06929 April 1991 225 6.0-7.6 138,88219 May 1997 232 3.1-4.6 15515

November2007 223 -- 3363

25 May

(AILA)2009 92 -- 190

TABLE 2: Major cyclones that hit the Bangladesh coast4

3.3 RIVER BANK EROSION:River Bank Erosion refers to the wearing off; of the top soil

that encloses a river or a stream. This is an ongoing disaster

and there is no specific indicator to measure the extent of

damage. So the extent of damage caused by river erosion in

most cases is based on various reports/information. Needless

to say whatever the difference in ascertaining the extent of

damage river erosion causes huge loss of property throughout

4 Source: Bangladesh Meteorological Department 2007.

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Figure 4: River Bank

the year. According to “World

Disaster Report 2001”

published by IFRCS every year

about 10, 00,000 people are

affected by river erosion and

9,000 hectare cultivable

lands are banished in river.

Among these only a few affected people are able to find new

shelters while others become homeless for uncertain period.5

River bank erosion in Bangladesh is no less dangerous than

other sudden and devastating calamities. Losses due to river

erosion occur slowly and gradually. Though losses are slow and

gradual, they are more destructive and far-reaching than other

sudden and devastating calamities. The effects of river

erosion are long-term. It takes a few decades to make up the

losses, which a family has incurred by river erosion. There

has been little progress, however, for improving the lives of

erosion-affected people due to resource constraint.

5 http://www.saarc-sadkn.org/countries/bangladesh/hazard_profile.aspx#top. Date Access: 15.02.2014.

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3.4 LANDSLIDE:Landslide is the collapse of a mass of earth or rock from a

mountain or cliff. Large and small landslides occur almost

every year in nearly all regions of the world. In the past,

landslide was not considered a major hazard in Bangladesh.

However, recently landslide has emerged as a major hazard,

particularly after the Chittagong Landslide 2007. Due to heavy

rainfall during 10-11 June 2007, landslides collapsed walls

which caused widespread damages in six areas of Chittagong

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Map 4: Bangladesh River Bank Prone Areas

city and in different Upazilas of the District. 50mm of

rainfall was recorded from 12:00 AM on 10 June 2007 to 6:00 AM

on 11 June 2007, and 315mm of rainfall was recorded from

6:00am to 2:00 PM on 11 June 2007. More than 120 people have

been reported dead due to Chittagong landslide.

Year Death Location

2012 122Chittagong, Cox’s Bazar,

Bandarban2010 96 Cox Bazar2008 11 Chittagong2007 127 Chittagong

TABLE 3: Recent Major Landslide in Bangladesh

3.5 EARTHQUAKE:

Earthquake is the sudden

violent shaking of the ground,

typically causing great

destruction, as a result of

movements within the earth's

crust or volcanic action. In 1993, 26 percent

of Bangladesh falls in high risk, 38 percent moderate and 36

percent in low risk zone in terms of earthquake vulnerability.

The distribution of recorded earthquakes indicate a major

clustering of seism city around the Dauki Fault and scattering

of other events along other major fault systems of Bangladesh.

The magnitude of the earthquakes are moderate (4-6) and

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Figure 5: Earthquake in Bangladesh

majority of them are shallow depth. The historical records

show that the there have been some major earthquakes

in Bangladesh. 6

The 1548 earthquake had affected Sylhet and Chittagong with

reports of ground rupture and hydrological changes. The 1762

earthquake had raised the Foul Island by 2.74 meters and the

northwest coast of Chedua by 6.71 meters above the MSL and had

caused permanent submergence of part of Chittagong. The 1897

Great India earthquake had caused extensive damage to parts of

Mymensingh, Dhaka and Rajshahi. Among the recent major

earthquakes, the 1997 Chittagong earthquake caused extensive

damage to the adjacent areas. In the context of human exposure

in seismically hazardous zones, nearly 1,330,958 people are

present in these zones and Bangladesh ranks 17th among 153

nations. Similarly, the modeled amount of GDP in seismically

hazardous zones puts Bangladesh 42nd among 153 countries.

6 http://www.saarc-sadkn.org/countries/bangladesh/hazard_profile.aspx#top.

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Figure 4: Earthquake Affected Areas in Bangladesh

In the context of human exposure in seismically hazardous

zones, nearly 1,330,958 people are present in these zones and

Bangladesh ranks 17th among 153 nations. Similarly, the

modeled amount of GDP in seismically hazardous zones puts

Bangladesh 42nd among 153 countries.

Date Name Magnitude(Richter)10 January, 1869 Cachar Earthquake 7.514 July, 1885 Bengal Earthquake 7.0

12 June, 1897Great Indian

Earthquake8.7

8 July, 1918 Srimongal 7.6

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Map 4: Earthquake Zoning Areas in Bangladesh

Earthquake2 July, 1930 Dhubri Earthquake 7.1

15 January, 1934Bihar-Nepal

Earthquake8.3

15 August, 1950 Assam Earthquake 8.5

3.6 DROUGHT:Drought is the prolonged periodof abnormally low rainfall,leading to a shortage of water.Every year parts of Bangladeshexperience drought when rainfallis normally low. In the countryabout 2.7 million hectares is severely drought prone causinghardship to poor agricultural laborers and others. UsuallySevere drought occurs in the north-western and south westernregion of the country. Droughts occurred in Bangladesh 24times between 1949 and 1991. Very Severe droughts hit thecountry in 1951, 1957, 1958, 1961, 1972, 1975, 1979, 1981,1982, 1984, 1989 and 1995. Bangladesh experiences two majorspells of drought: Kharif (June/July to October) especially inthe highlands of the Barind tract and Rabi and Pre Kharif(January to May) due to dry days and low soil moisture. InBangladesh nearly 642,277 people are exposed in areas underthe threat of drought; ranking it 63rd among the 184 countriesanalysed.7

7 http://www.saarc-sadkn.org/countries/bangladesh/hazard_profile.aspx#top.

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Figure 6:Drought

TABLE 4: List of Major Earthquakes Affecting Bangladesh

3.7 TORNADO:The two transitional periods between southwest and northeast

monsoons over the Indian sub-continent are characterized by

local severe storms. The transitional periods are usually

referred to as pre-monsoon (March-May), and post-monsoon

(October- November). It is the pre-monsoon period when most of

the abnormal rainfall or drought conditions frequently occur

in different parts of Bangladesh. Also there are severe local

seasonal storms, popularly known as nor’westers

(kalbaishakhi). Severe nor’westers are generally associated

with tornadoes. Tornadoes are embedded within a mother

thundercloud, and moves along the direction of the squall of

the mother storm.

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Figure 7: A scene of tornado in Bangladesh

Map 5: Drought Affected Areas in Bangladesh

The frequency of devastating

nor’westers usually reaches

the maximum in April, while a

few occur in May, and the

minimum in March. Nor’westers and tornadoes are more frequent

in the afternoon. Table 3 shows some of the devastating

nor’westers and tornadoes that hit Bangladesh. Nor’westers may

occur in late February due to early withdrawal of winter

from Bangladesh, Bihar, West Bengal, Assam, and adjoining

areas. The occasional occurrence of nor’westers in early June

is due to the delay in the onset of the southwest monsoon over

the region (Karmakar, 1989).8

Date Location14 April 1969 Demra (Dhaka)17 April 1973 Manikganj (Dhaka)10 April 1974 Faridpur11 April 1974 Bogra09 May 1976 Narayanganj01 April 1977 Faridpur26 April 1989 Saturia (Manikganj)14 May 1993 Southern Bangladesh13 May 1996 Tangail04 May 2003 Brahmanbaria21 March 2005 GaibandhaTABLE 5: Some of the devastating nor westers and tornadoes

4. STATISTICS OF NATURAL DISASTERS IN BANGLADESH: Bangladesh has a long history of natural disasters. Between

1980 and 2008, it experienced 219 natural disasters, causing

8 http://www.saarc-sadkn.org/countries/bangladesh/hazard_profile.aspx#top

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over US$16 billion in total damage. The predicted effects of

climate change will only compound these impacts.

Disaster Date Killed Disaster Date AffectedFamine 1943 1,900,000 Flood 22-Jul-

1987

73,000,00

0Epidemic 1918 393,000 Flood Aug-1988 73,000,00

0Wind

Storm

12-Nov-

1970

300,000 Flood Jul-1974 38,000,00

0Wind

Storm

30-Apr-

1991

138,866 Flood May-1984 30,000,00

0Wind

Storm

Oct-1942 61,000 Drought 5-Jul-

1983

20,000,00

0Wind

Storm

11-May-

1965

36,000 Flood Jul-1968 15,889,61

6Flood Jul-1974 28,700 Wind

Storm

11-May-

1965

15,600,00

0Wind

Storm

Jun-1965 12,047 Wind

Storm

30-Apr-

1991

15,438,84

9Wind

Storm

28-May-

1963

11,500 Flood 8-Jul-

1998

15,000,05

0Wind

Storm

9-May-

1961

11,000 Flood 15-Jun-

1995

12,656,00

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TABLE 6: Incidence of Natural Disasters in Bangladesh

5. CAUSES BEHIND NATURAL CALAMITIES: Natural disasters are very common in Bangladesh due to her

peculiar geograph. The funnel shaped coast helps cyclones

which are formed in the Bay of Bengal to land in Bangladesh.

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Again, heavy rainfall, tidal, bores, melting of snow of the

Himalayas cause floods here. Global warming is another factor

in causing natural calamities. Natural calamities cause

maximum damage in Bangladesh. This is because of the low flat

land, high density of population, poorly built houses and also

lack of drastic plans.9

6. EFFECTS OF NATURAL DISASTERS:Natural disasters have become so commonplace that they hardly

receive passing notice on the news unless there have been a

large number of casualties. Volcanoes, mudslides, tsunamis and

floods are just a few of the ways nature strikes on a daily

basis, leaving behind destruction and heartache. Humans have

learned to prepare for the possibility of tornadoes,

earthquakes, hurricanes and wildfires, but no amount of

preparation can lessen the impact that natural disasters have

on every aspect of society.10

6.1 Physical Destruction:

The biggest visible effect of natural disasters is the

physical ruin they leave behind. Homes, vehicles and personal

possessions are often destroyed within a short period of time,

leaving families homeless and shutting some businesses down

permanently. Tornadoes destroy structures at whim, earthquakes

can cause structural damage that might not be apparent at

9 http://www.ghior.com/2013/02/natural-calamities-or-disasters-in.html.10 http://www.slideshare.net/SayefAmin1/natural-disaster-its-causes-effects.

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first glance, and tsunamis and floods sweep homes off their

foundations.

6.2 Emotional Toll:

Possessions are not hard to replace, as many people keep

insurance on their property and tangible goods. The emotional

toll of natural disasters is much more devastating. The death

of a loved one may be the worst-case scenario but its not the

only lasting emotional effect victims experience. Whole

communities may be displaced, separating friends and

neighbors; victims face anxiety and depression as they wonder

if it could happen again. In extreme cases, they may

experience post traumatic stress disorder (PTSD).

6.3 Economic Concerns:

According to the National Hurricane Center, Hurricane Katrina

cost the U.S. $75billion when it slammed into New Orleans in

August 2005. That doesn’t include the damage caused in the

Florida counties of Miami-Dade and Broward by the same storm.

While destruction of this magnitude is not commonplace, even a

minor storm can cause considerable damage. At the very least,

the local economy must be able to absorb the cost of cleanup

and repairs.

6.4 Indirect Effects:

While the visible effects of natural disasters are immediate

and strongly felt, communities that surround ground zero can

be indirectly affected by them as well. Natural disasters

almost always lead to a disruption in utility services around

the area impacted. This can mean life or death for those who

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rely on dialysis or oxygen to live. Medical assistance is also

often slowed, as emergency crews must focus on the victims of

the disaster. Banks and other businesses might be closed,

affecting a family’s ability to withdraw money to pay bills

and buy groceries.

6.5 Disruption of Utilities:

Communities that surround areas affected by natural disasters

are seriously affected by the disruption caused to utility

services. Generally, power is the first thing to go when there

is a natural disaster. This can literally mean life or death

to the people who are on life support systems such as oxygen

and dialysis. Medical assistance becomes hard to get since the

crews are busy helping the victims of the disaster. Banks can

be shut down; causing a shortage of cash circulation that

prevents people from accessing funds for much needed

provisions for babies and small children.

6.6 Emotional Damage:

When a natural disaster strikes, the emotional toll on the

people affected is quite devastating. While possessions can be

replaced eventually through insurance, the emotional damage

can take a long while to heal. People lose loved ones in

natural disasters; deaths of people and precious pets, serious

injury and people missing all add up to severe emotional

trauma. Communities get displaced meaning separation from

family and friends. Victims face stress, trauma, anxiety and

depression as a result of natural disasters.

6.7 Social Consequences:

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The social consequences of natural disasters in the short and

long term are wide ranging. The disasters affect housing;

people are left homeless and rebuilding a home takes a long

time and a lot of money. Health care infrastructure is

affected; the impacts are worse in developing countries that

already have poor facilities to begin with. Disease starts

spreading and, without proper medical attention, makes a bad

situation worse. Education is a big loser when a natural

disaster happens, schools are often closed, teachers are

unable to come in to work and children are displaced and

unable to attend school. Transportation capacity is reduced

hindering relief efforts and disrupting normal life.

7. PROTECTIVE MEASURES FOR NATURAL DISASTERS IN BANGLADESHNatural disaster, being a natural phenomenon, it is not

possible to prevent. We can take some protective measures to

lessen the sufferings of the victims. Both long and short term

plans can be taken. Government must take projects for

forestation. In addition, warning and preparatory measures

have to be improved. Finally we should rise awareness in

people to protect our lives and properties from the tremendous

attack of natural calamities. Concerted efforts for the

lessening of the sufferings of the victims can play a vital

role in mitigating natural disasters in Bangladesh.

8. CONCLUSION:Natural calamities cause huge loss to our country every year.

However, the effect of those may be mitigated with the

combined efforts of both the government and the mass people.

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