Coastline dynamics and raising landform: A Geo-informatics Based Study on the Bay of Bengal, Bangladesh

Abstract

The southern part of Bangladesh is bounded by the Bay of Bengal. Three major river systems which are: Brahmaputra-Jamuna, Ganges-Padma and Surma-Kusiara have developed the Ganges-Brahmaputra-Meghna (GBM) floodplain, this covers 80% area of Bangladesh. These rivers carry huge sediments from upper Himalayan region during monsoon period. On the contrary, as the costal part of Bangladesh is open to the sea, so high wave actions, strong wind flow, tidal actions are prevailing here. Consequently, coastline of this part is unstable and dynamic. Coastline change dynamics is significant for disaster management, coastal planning and environmental management. Rennell's map (1776), Landsat MSS (1976) and Landsat OLI (2016) images have been used to explore the coastline using tools of Remote Sensing and Geographic Information System (GIS) of Geo-informatics. During 240 years since 1776 to 2016 about 3892 km2 land instead of landform have been raised in coastal area of Bangladesh.