Field observation and numerical simulation of past and future storm surges in the Bay of Bengal: case study of cyclone Nargis

Storm surges are one of the most important risks to coastal communities around the Bay of Bengal, and it is feared that the threat they pose will increase with climate change in the future. To understand the threats that these events pose, a summary of the field surveys performed in Yangon River Basin after cyclone Nargis in Myanmar in 2008 is presented. Though due to government restrictions survey activities were limited to the area near Yangon city, it was found out that the tide due to the storm surge was probably between 3 and 4 m high and travelled around 50 km upstream of the river mouth of Yangon River. Cyclone Nargis could be accurately reproduced using a numerical model that integrated weather, wave, coastal ocean models, and tide prediction system. The application of such an integrated model is relatively new for storm surge simulation and has never been used for the Bay of Bengal storms. The model was then used to also simulate future cyclones over the Bay of Bengal considering a future climate change scenario.