Natural Hazard is a common phenomena of Bangladesh which makes visit here every year. It contains a detail study about the natural hazards of Bangladesh with its seasonal distribution, causes, effects and necessary maps. An extended Hazard Calendar has been added here.

1. A presentation on
Natural Hazard in BD
Prepared By:
Minhaz Hasan Sujan
First Semester (Masters)
Dept. of GEE,SUST
Contact: minhaz.hasan46@gmail.com
DEPARTMENT OF GEOGRAPHY AND ENVIRONMENT
SHAHJALAL UNIVERSITY OF SCIENCE AND TECHNOLOGY,
Sylhet, 3114

2. Natural Hazards in Bangladesh
(location, impact & Seasonal
Distribution)

4. Major Natural Hazard
Major Natural Hazard in BD

5. Hazard Calendar of Bangladesh
©minhaz.hasan46@gmail.com

6. Seasons Period Disaster Rainfall Picture
Pre-
monsoon
Mar-May • Thunder Storm, Hail,
• Tornado, Cyclone,
• Heat wave, Drought,
• Nor’ easter
19%
Monsoon Jun- Sep • Monsoon Depression,
• Flood,
• River Bank Erosion,
• Land Slides
71%
Post-
monsoon
Oct-Nov • Cyclone,
• Tornado
08%
Winter Dec-Feb • Abnormal Dryness,
• Cold Wave
02%
Seasonal Distribution of Hazard in BD

7. Flood

8. Natural Hazard: Flood
Types of Flood in BD:
Three types:
1. Rainfall Flood
2. River Flood
3. Flash Flood
4. Tidal flood
Areas Affected:
 Floodplains of the Brahmaputra-
Jamuna,
 The Ganges-Padma and
 The Meghna river system
 Haor Basins of the North-east region
and
 South-eastern hilly areas

10. Year
Flooded
Area (Km2)
Percentage of
Total Area
Number of
Deaths
Crop
Damaged
(MT)
Financial
Loss (mil
taka)
1954 36920 25 112 0.7 1,500
1955 50700 34 129 ------- -----
1956 35620 24 --------- 0.5 1,580
1962 37404 25 117 1.2 1,500
1963 43180 29 --------- ------- ------
1968 37300 25 126 1.1 1,200
1970 42640 28 87 1.2 1,000
1971 36475 24 120 ------- ------
1974 52720 35 1987 1.4 20,000
1984 28314 19 513 0.7 45,00
1987 57491 38 1657 1.5 35,000
1988 77700 52 2379 3.2 40,000
1998 100000 68 1050 4.5 1,42,160
Data Source: Journal of the Faculty of Environmental Science and Technology,
Okayama University Vol 8, No. 1, Page: 56 & 59, March 2003
Effects of Flood

11. Effects of Flood

12. Effects of Flood

13. Is flooding in Bangladesh always a bad thing?
Replenish
groundwater
reserves
Provide
nutrient
rich
sediment
for farming
Reduce the
need for
artificial
fertilisers
Provide fish

14. Cyclone and Storm Surge

15. Cyclone and Storm Surge
Cyclone a tropical STORM or atmospheric turbulence involving circular motion
of winds, occurs in Bangladesh as a NATURAL HAZARD

16. Classification
Cyclones in Bangladesh are presently
classified according to their intensity
and the following nomenclature is in
use:
1. depression (winds upto 62 km/hr)
2. cyclonic storm (winds from 63 to
87 km/hr),
3. severe cyclonic storm (winds from
88 to 118 km/hr) and
4. severe cyclonic storm of hurricane
intensity (winds above 118 km/hr).

17. 1. Cyclone wind come from
South- West side.
2. 70% Cyclone occurs in
Spring and Summer
season.
3. Bangladesh is severely a
ffected by Cyclone
4. Main cause for cyclone is
geographical location
 710 km long coast line.
 19 districts, 147 upazillas
of the country.
 Out of these 19 districts,
only 12 districts meet the
sea or lower estuary
directly.
 48 in 12 districts.
Cause of Cyclone in BD

18. Cyclone in BD: Sidar- Nov, 2007

19. Kutubdia Island,
Bangladesh.
40,000 of population
of 110,000 reported
dead. Bangladesh.
May 1991
Sidar Impacted
people after having
the aid

20. Flooding by storm surge in Bangladesh can be classified as
follows:
a) Normal coastal flooding - no damage on crops,
b) Moderate coastal flooding - very limited damage on
crops,
c) Moderately high coastal flooding - high damage on
crops but relatively low damage on properties
and lives,
d) High coastal flooding - large scale damage on crops,
properties and lives,
e) Severe coastal flooding - severe damage on crops,
properties and lives.
Approximate percentage of storm surge impact:
Region Percentage
Bangladesh 40
Asia (excluding Bangladesh) 20
North America 20
Europe 10
Africa and South America 5
Australia and New Zealand 5
(Source: Murty and El-Sabh, 1992)

21. Drought

22. Drought Is
A lack or of for an unusually
period of , involving less than the usual
over 3 months
Meteorologi
cal drought
Hydrological
drought
Agricultural
drought
Socio-economic
drought

23. Impact of Drought

24. Impact of Drought

25. Drought Impacted Areas

26. April 30, 1989, in Saturia
Tornado

27. Tornado Impacted Areas

28. 1. April 11, 1964: Narail-Magura,
500 Fatalities
2. April 14, 1969: East Pakistan,
660 Fatalities + injuring 4,000
people.
3. April 17, 1973: Manikganj, Singair and
Nawabganj,
681 Fatalities + 1 village and 9
towns
4. April 1, 1977: Madaripur-Shibchar,
500 Fatalities + 400 (another)
5. April 26, 1989: Daulatpur-Salturia,
1,300 Fatalities, 12,000 (inj),
destroyed 80,000 homes
6. May 13, 1996: Mirzapur-Madarganj,
700 Fatalities + 30,000 homes
Impact of Tornado (past)

29. • Loss of lives and biodiversity.
• Destruction of property
• Damage of cash crops
• Damage to essential services
• National economic loss and loss
of livelihood
Impact of Tornado (past)

30. Impact of Tornado (past)

31. EARTHQUAKE

32.  Zone 1:High Risk
Mymensing,Sylhet,Rang
pur,Lalmonirhat,
Kurigram etc.
 Zone 2:Moderate Risk
Bogra, Dinajpur, Dhaka,
Comilla, panchgar etc.
 Zone 3:Low Risk
Khulna, jessor, Barisal,
Patuakhali etc.
Earthquake Zone of BD

33. Year Name Magn
itude
Distance
Capital(k
m)
Affected Area
1869 Cachar Earthquake 7.5 250 Assam, Monipur, Sylhet
1985 Bengle Earthquake 7.0 170 Jamalpur, Mymensing, Bogra
1897 Great Indian
Earthquake
8.7 230 Assam, Sylhet, Rangpur
1918 Srimangal Earthquake 7.6 150 Whole Sylhet to Dhaka
1930 Dubri Earthquake 7.1 250 Rangpur
1934 Bihar-Nepal Earthquake 8.3 510 Nepal, India, Bangladesh
1950 Assam Earthquake 8.5 780 Assam, Whole Bangladesh
1987 Sylhet Earthquake 5.6 200 Northern Bangladesh
1997 Bandarban Earthquake 6.0 325 South-eastern part
1999 Maheskhali Earthquake 5.1 350 Maheskhali
2003 Barkal Earthquake 5.1 350 Barkal
2015 Nepal Earthquake 7.9 745 Nepal, India, Bangladesh
Earthquake History

34. • Ground shaking: Shaking of the ground caused by
the passage of seismic waves, especially surface
waves near the epicenter of the earthquake are
responsible for the most damage during an
earthquake.
Impact of Earthquake

35. • Damage to man-made structures: Damage to man-made
structures, such as roads, bridges, dams and buildings from
ground motion.
Impact of Earthquake

36. • Fires: Fires, often associated with broken electrical
and gas lines, is one of the common side effects of
earthquakes..
Impact of Earthquake

37. • Flooding: Flooding can come from many sources such as
broken water main pipes, dams that fail due to the
earthquake and earthquake-generated tsunamis.
Impact of Earthquake

38. • Give knowledge insight in Geology
• Push Minerals and Metals to the Surface
• Make Fossil Fuels Easier to Access
Positive Impact of Earthquake

39. LANDSLIDE

40. • Chittagong & Chittagong hill
tracts*
• Hill Ranges of Northeastern
Ranges of Northeastern Sylhet
• Hill along the narrow northern
strip of Mymensingh.
Landslide Vulnerability in
Chittagong City High Risk
Areas
Lebubagan Area
Baizid Bostami Area
Kushumbag Residential
Area
Batali Hill Area
M tijh o arna Area
Landslide: Impacted Areas

41. Effects and losses due to landslides
A) Direct Effects:
• Physical Damage-Debris may block roads, supply
lines (telecommunication, electricity, water, etc.) and
waterways.
Causalities- deaths and injuries to people and
animals.
B) Indirect Effects:
• Influence of landslides in dam safety- failure of the
slopes bordering the reservoir, Flooding caused by
movements of large masses of soil into the reservoir.

42. • Landslides and flooding- Debris flow can cause flooding
by blocking valleys and stream channels, forcing large
amounts of water to backup causing backup/ flash flood.
C) Direct losses:
• Loss of life, property, infrastructure and lifeline facilities,
Resources, farmland and places of cultural importance.
D) Indirect losses:
• Loss in productivity of agricultural or forest lands,
Reduced property values, Loss of revenue, Increased cost,
Adverse effect on water quality and Loss of human
productivity,
Effects and losses due to landslides (Cont…)

43. Environmental impact on landslides
The topography of the earth’s surface
The character and the quality of rivers and
The character and the quality of rivers and
streams and the groundwater flow
The forest that cover much of the earth’s
surface
The habitats of natural wildlife that exist on
the earth’s surface
Effects and losses due to landslides (Cont…)

44. River Bank Erosion

45. RBE: Impacted Areas
The Padma bank
erosion
The Meghna bank
erosion
Brahmaputra-jamuna
bank erosion

46. RBE: Impacted Areas
Padma river bank erosion, at Kustia

47. Over 25,000
families were
rendered
homeless in June
1993 by
riverbank erosion
in 16 districts
The widening of
Jamuna in a 28-
year period
resulted in a loss
of floodplain of
70,000 ha
Impact of RBE

48. Cold Wave

49. Cold Wave: Impacted Areas

50. Cold Wave:
Impacted
Areas

51. producing crops is hampered (boro, vegetable, mustard,
wheat, potato)
All most in every year some people die due to blow of
chilly wind in winter season (cholera, diarrhea and
pneumonia)
There has been a negative impact of the cold wave
situation on poultry and cattle,
Year Impacted District Died People
2011 21 39
2012 22 72
2013 24 80
2014 22 69
2015 13 75
Cold Wave: Impacts

52. Thunderstorm

53. Bangladesh declares THUNDERSTORM a
DISASTER as death surge- June, 2016.
BMD data says: 1476 died in 2010.
261 died in 2016 (South Asia=> 265)
On may 12-13, 2013: died about 82 people
Thunderstorm: Impact

54. Faridpur:+8.598
Sylhet:-4.704
Rangpur:+5.207
Sylhet:-4.626
Fig. Spatial distribution of the trends of
TS Frequency (/10 year) over
Bangladesh in March during 1980-2008
Fig. Spatial distribution of the trends of
TS Frequency (/10 year) over
Bangladesh in April during 1980 -2008
Thunderstorm: Impacted Areas

55. Disaster Prone
Areas of
Bangladesh