1. Mohammad Khaled Akhtar Bangladesh
23/11/2018
A Step Towards Narrowing the Gaps in the field of Water Resources Management by Satellite Estimated Rainfall Data
Mohammad Khaled Akhtar
Bangladesh

2. Outline: Introduction & background Objective Methodology
23/11/2018
Introduction & background
Objective
Methodology
Data collection & processing
Model development
Result analysis
Summary

3. Introduction & Background:
Flooding is an annual recurrent event in Bangladesh
Total protection against flood is neither possible nor feasible
A basin model with reasonable accuracy could alleviate the problem to some extent by flood forecasting and disaster preparation application

4. Introduction & Background:
Flood Damage:
Area affected by flood – 38 districts
Crop Damage:
fully-793,140 hectares
partly- 656,187 hectares
Affected People –10 million;
People taking refuge – 373,939 in 1601 shelters;
Housing units destroyed – 89,048
Deaths – 192.
(Year: August 2007)
November 23, 2018

5. Introduction & Background
Study Area:
Area: 583x103 km2
Length: 2,900km
Area: 65 x 103 km2
Length: 930km
Area: 907x103 km2
Length: 2,500km
Bangladesh (145,000 km2)
November 23, 2018

6. Introduction & Background
Causes of flood:
Low topography of the country with excessive runoff from the drainage basins (92% of its located outside Bangladesh)
Coast line is conical in shape
Backwater effect and poor drainage facilities
November 23, 2018

7. Objectives: Specific objectives:
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To develop the GBM basin model using remotely sensed data, which can provide enough flood information few days ahead
Specific objectives:
To develop a simulation model of the GBM basin with remotely sensed data
To compare the measured discharge with the total amount of rainfall
To simulate basin discharge under climate change scenarios
Climate change and how it affects the sustainability of the current socio-economic system
Providing an analysis tool for decision makers to view outcomes of policies and programs
Approaches to system modelling that are based on feedbacks between different components of social-economic-climatic system
The Overall Point:
Through modelling global change, we gain a better understanding of the entire system
 We hope, of course, that better understanding translates to better policies

8. Field observation (BWDB)
Methodology:
Result comparison
TRMM
Internet
Catchment parameter
Rainfall
Temperature
Evaporation
Field observation (BWDB)
Discharge
RR model
Model output
November 23, 2018

9. Data Collection & Processing:
Data sources:
Rainfall (TRMM- 3B42RT)
Discharge (BWDB, IWM)
DEM (IWM, USGS)
Evaporation (NASA)
Soil Type (FAO, ISRIC)
Land-use (USGS)
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10. Data Collection & Processing:
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11. Model Development:
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12. Model Development:
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13. Model Result: Area: 583x103 km2 Length: 2,900km Area: 907x103 km2
Bahadurabad
Hardinge bridge
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14. Result analysis:
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15. Result analysis:
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16. Result analysis:
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17. Model Result: Area: 583x103 km2 Length: 2,900km Area: 907x103 km2
Bahadurabad
Hardinge bridge
November 23, 2018

18. Result analysis:
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19. Result analysis:
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20. Result analysis:
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21. Result analysis: Sensitivity test:
In this study sensitivity analysis is carried out to have some idea, how model will perform if present time data is used as future data when rainfall forecast data is not available.
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22. Result analysis:
Sensitivity test:
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23. Performance of 3 to4-day forecast is quit acceptable for this case
Result analysis:
Sensitivity test:
Performance of 3 to4-day forecast is quit acceptable for this case
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24. Result analysis: Impact of climate change:
Few simple model simulations were carried out to see the impact of climate change on the basis of changing rainfall volume even though the model is not well calibrated. A very crude estimation is applied by increasing rainfall by 20% and 40% and a decrease of rainfall by 20% for Ganges basin.
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25. Result analysis:
Impact of climate change:
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26. Summary: The satellite derived rainfall data is very promising
Yearly accumulated volume of rainfall over the Ganges basin and generated runoff at the outlet varies within acceptable range.
On the other hand, the accuracy of satellite measured rainfall over Brahmaputra basin is beyond the acceptable range
Sensitivity analysis gives some indication about the forecasting condition, if no rainfall forecast is available, which is very encouraging in the field of flood forecasting
Further efforts are needed to improve the model performance to make it operational
November 23, 2018

27. Summary:
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Consistency and accuracy of the satellite data needed to be checked before further calibration especially for the Brahmaputra basin area
More detailed analysis should be carried out to say anything concrete on the generated runoff of GBM basin considering the climate change scenario
It is hoped that there will be significant improvement in the model performance if validated rainfall data can be used

28. 23/11/2018
Thank You