Chapter 4 - Storm Surge Due to 2008 Cyclone Nargis in Myanmar and Post-cyclone Preparedness Activities

Abstract

Countries around the Bay of Bengal are often threatened by the devastation of storm surges associated with tropical cyclones. Especially, the low-lying deltaic regions of Bangladesh and Myanmar are particularly vulnerable to storm surges. Cyclone Nargis hit the southern part of Myanmar on May 2nd and 3rd 2008 and caused an enormous number of human casualties, as well as widespread damage to infrastructure and housing in the downstream areas of the Ayeyarwady Delta and Yangon Rivers. In this chapter, field surveys performed by the authors along the Yangon River Basin and Ayeyarwady Delta after Cyclone Nargis in Myanmar are presented. At the same time, a numerical simulation of the storm surge due to cyclone Nargis was also carried out by using a WRF-SWAN-Coastal ocean-Tide coupled model. The model simulated storm surge level shows good agreement with the field survey observations in all locations. The model was then used to also simulate future cyclones over the Bay of Bengal considering a climate change scenario by the year 2100 to attempt to understand the kind of threat posed by an event with a similar return period by the turn of the twenty-second century.