RAL SEMINAR: Climate Change Impacts on Extremes in Bangladesh: Floods and Cyclonic Storm Surges

People in South Asia, where people’s livelihoods are highly dependent on water resources, can be affected disproportionally under the warming world. The Ganges-Brahmaputra-Meghna (GBM) river system plays a key role in the survival and development of more than 670 million people in South Asia. This talk discusses how freshwater availability and climate extremes such as floods and droughts of the GBM river basins in Bangladesh will likely be affected by global warming at different warming levels, using a hydrologic modeling analysis of the flows in the GBM river system utilizing multi-model regional climate projections. How the results of this study were used by the Bangladesh government to develop guidelines for climate-resilient infrastructures in the northwestern flood-vulnerable areas, along with adaptation options for agricultural and water management of these three river systems will also be discussed.
This talk also discusses two climate change mitigation and disaster risk management strategies that have been developed for current-day Bangladesh vulnerabilities. A real-time flash flood forecasting system based on WRF, hydrologic (HEC-HMS), and hydrodynamic (HEC-RAS) models has been developed to protect the northeast region of Bangladesh, which is highly vulnerable to flash floods that damage the Boro rice crop of that region. As well, coastal communities of Bangladesh are highly vulnerable to storm surge and their impacts from increasing frequency and the intensity of tropical cyclones. We have developed an increased accuracy storm surge inundation model using historic Bay of Bengal cyclone tracks and inundation records that could be used for operational storm surge inundation forecasting and early warnings.