The Monsoon in Bangladesh

This book presents comprehensive aspects of climatological characteristics of the monsoon seasonal transitions associated with the atmospheric circulation in Bangladesh, focusing on the pre-monsoon, monsoon and post monsoon seasons. In addition, the onset and withdrawal phases were examined using pentad and 20-day mean wind, moisture flux, precipitable water and rainfall distributions. These were obtained from Japanese 25-year re-analysis (JRA-25) data and rainfall data from the Bangladesh Meteorological Department (BMD).

Analysis of the pentad and 20-day mean the horizontal wind at 850 hPa, the total column water vapor flux, the precipitable water and rainfall distribution around Bangladesh showed that, the onset and withdrawal of the summer monsoon seasons in Bangladesh occurred between Panted 31 (May 31–June 4: P31) and P32 (June 5–9) and between P56 (October 3–7) and P57 (October 8–12), respectively.

The dramatic changes have occurred during the monsoon onset period, between P31 and P32. At this time southerly wind, water vapor flux, and precipitable water are shown drastically stronger over the BoB and Bangladesh. Drastic changes also have shown in rainfall distribution maps in P31-32, when abrupt increases in precipitation.

Remarkable changes also have shown between P56 and P57, which is regarded as withdrawal of summer monsoon. At this time southwesterly flow vanished not only in and around Bangladesh, but also in almost the whole Indian Ocean and Indian subcontinent. Eventually the rainfall distribution maps have showed decrease in rainfall in P56-57.

The disastrous floods in Bangladesh captured world-wide attention. An understanding of the dynamics of the monsoon floods in Bangladesh, this study conducted real time flood monitoring mapping and assessing for the floods of 2000 to 2004 around northeast region in Bangladesh, using LANDSAT, RADARSAT, GIS and ground data. A supervised classification technique was used for this processing. The results imply that maximum extent of the inundation area as estimated using RADARSAT satellite imaging in 2004, which is corresponded well with the heavy rainfall and the highest water level of the Ganges–Brahmaputra–Meghna (GBM) Rivers. It has demonstrated that RADARSAT data acquired over Bangladesh have the ability to precisely assess and clarify inundation areas allowing for successful flood monitoring and mapping and disaster management. This study also presents unique flood hazard and flood damage maps, which are expected to be useful for future planning and flood disaster management.

It is believed that the contribution made by this book will be valuable for that student who wants to learn the climate, monsoon and flood and an introduction to the field of Geography.

This book features in: Academic and Reference Books for the Monsoon in Bangladesh and Flood monitoring mapping and assessing studies in Geography.

Write a review

Do you have any questions about The Monsoon in Bangladesh?