1. Analyzing changes of temperature over Bangladesh due to global warming using historic data
Dr. A.K.M. Saiful Islam
Associate Professor
Bangladesh university of engineering and technology

2. Introduction
Intergovernmental Panel on Climate Change (IPCC) has reported in their fourth assessment report that global surface temperature increased 0.74 ± 0.18 °C during the 100 years ending in 2005.
In this context, long term changes of near surface air temperature over Bangladesh have been studied using the available historic data collected by the Bangladesh Meteorological Department (BMD).

3. Data
Maximum and minimum daily temperature data of last sixty years ( ) collected from 34 stations of BMD located all over the Bangladesh have been used in this study.
Trend analysis has been conducted on monthly data for all the stations

4. Study Area

5. Trend Analysis
Increase C on 100 years scale

6. Trends of Minimum Temp
Increase C on 100 years scale

7. Trends of Temperature For 34 ground measuring Stations of BMD ID
Latitude
Longitude
Altitude
Max. Temp. (0C per yr.)
Min. Temp. (0C per yr.)
11704
Barisal
22.72
90.37
2.1 m
0.0077
11706
Bhola
22.68
90.65
4.3 m
0.0170
0.0206
10408
Bogra
24.85
89.37
17.9 m
0.0117
0.0404
11316
Chandpur
23.23
90.7
4.9 m
0.0163
0.0161
11921
Chittagong
22.35
91.82
33.2 m
0.0224
0.009
41926
Chuadanga
23.65
88.82
11.6 m
0.0217
11313
Comilla
23.43
91.18
9 m
0.0049
11927
Cox's Bazar
21.45
91.97
0.0295
0.022
11111
Dhaka
23.78
90.38
6.5 m
0.0119
0.0225
10120
Dinajpur
25.65
88.68
37.6 m
0.0151
11505
Faridpur
23.93
89.85
8.1 m
0.0275  
11805
Feni
23.03
91.42
6.4 m
0.0174
0.0331
11814
Hatiya
22.45
91.1
2.4 m
0.0261
10910
Ishardi
24.15
89.03
12.9 m
0.0032
0.0037
11407
Jessore
23.2
89.33
6 m
0.0147
0.0113
12110
Khepupara
21.98
90.23
1.8 m
0.0266
11604
Khulna
22.78
89.53
11925
Kutubdia
21.82
91.85
2.7 m
0.0416
0.0248
11513
Madaripur
23.17
90.18
7 m
0.0047   
11809
Maijdicourt
22.87
0.0193
0.0204
41958
Mongla
22.47
89.6
0.0430
0.0104
10609
Mymensing
24.73
90.42
18 m
0.0086
12103
Patuakhali
22.33
90.33
1.5 m
0.0328
0.026
10320
Rajshahi
24.37
88.7
19.5 m
0.0110
0.0027
12007
Rangamati
22.63
92.15
68.9 m
10208
Rangpur
25.73
89.27
32.6 m
0.0281
11916
Sandwip
22.48
91.43
2 m
0.0074
11610
Satkhira
89.08
4 m
0.0065
0.0107
41858
Sayedpur
25.75
88.92
39.6 m
11912
Sitakunda
91.7
7.3 m
0.0581
10724
Srimangal
24.3
91.73
22 m
0.0030
0.0237
10705
Sylhet
24.9
91.88
33.5 m
0.0057
41909
Tangail
24.25
89.93
10.2 m
11929
Teknaf
20.87
92.3
5 m
0.0242
0.0236
Trends of Temperature
For 34 ground measuring
Stations of BMD

8. Trends of Maximum Temp.

9. Trends of Minimum Temp.

10. Maximum Temperature
Maximum increase: at Shitakunda
Minimum increase: at Rangpur
Minimum Temperature
Maximum increase: at Bogra
Minimum increase: at Tangail

11. Monthly temperature over Bangladesh (1948-2007)

12. Month-wise Trends Month Max. Temp. (0C per yr.) Min. Temp. January
0.0104
February
0.0000
0.0340
March
0.0220
April
0.0121
May
0.0010
0.0052
June
0.0139
0.0103
July
0.0116
0.0075
August
0.0183
0.0081
September
0.0070
0.0031
October
0.0178
0.0078
November
0.0270
0.0289
December
0.0147

13. Trends of minimum temp. in January
Increase C in 100 years

14. Trends of minimum temp. in February
Increase 3.5 0C in 100 years

15. Average Temperature in January (1948-2007)
Daily Minimum
Daily Maximum

16. Effect of Temperature rise on Agriculture
In winter season (Nov-Feb), the main crops of Bangladesh are:
Boro (rice), Wheat, Potato, vegetables.
Increase of winter temperature can reduce the environmental suitability for wheat, potato and other temperate crops grown in Rabi season.
It might benefit Boro paddy and kharif crops.

17. Wheat growing areas and minimum temperature trend map in January
Trends of minimum temp
Wheat coverage area

18. Effect on Potato: Temperature derived from MODIS data during January, 2006
Temperature map in January
Plantation starts on December
Potato Field in Munshigonj

19. Presently working
We are presently working on the future prediction of temperature trends using PRECIS regional climate change model.
Climate Change Study Cell has been formed in our university with vision of “to establish itself as the premier knowledge center on climate change risk and adaptation for Bangladesh”.

20. Conclusion
Both daily minimum and maximum temperature shows positive trends over Bangladesh. Increase of daily maximum temp. is C and daily minimum temp is C in 100 years.
Maximum increase of daily maximum temp. has occurred in November at 2.7 0C and daily minimum temp. has occurred in February at 3.4 0C in 100 years.
Maximum increase of daily maximum temp. has occurred as 5.810C at Shitakunda and daily minimum temp. has occurred as C at Bogra in 100 years.
Increase of winter temperature can reduce the environmental suitability for wheat, potato and other temperate crops grown in Rabi season.

21. Thank you