Author(s): Tansir Zaman Asik; A.S.M. Alauddin Al Azad; Rabeya Akter; Mohiuddin Sakib; Anisul Haque; Md. Munsur Rahman
Linked Author(s):
Keywords: Salinity; Tropical cyclone; Estuary; Sea level rise
Abstract: In a changing climate, saltwater intrusion is expected to worsen in low-lying coastal areas of Bangladesh. Both tropical cyclone (TC) in a sea level rise (SLR) are expected to exacerbate the current condition. In recent days, moderate intensity cyclones (like the recent cyclone MORA which made landfall in Cox’s Bazar coast on May 2017) are more frequent than high-intensity cyclone (like SIDR which made landfall in the east of Sundarbans coast on November 2007). In some recent studies, the landfall location of cyclone SIDR is found to be a hotspot when cyclone-induced salinity intrusion is considered. Accounting all these, this study considers a MORA-like cyclone to make its landfall at the SIDR landfall location (keeping the strength of MORA similar to its original strength). A plausible future is generated by assuming that MORA-like cyclone will be more frequent in future in a coastal setting which is experiencing sea level rise. In this study, a sea level rise of 0.5m is considered which is a likely scenario by the mid-century. To study this plausible future, scenarios are generated by applying the coupled Delft3D cyclone, flow and salinity models. The results show that when the cyclone landfall location at the eastern border of Sundarbans is considered in future, a MORA-like cyclone will cause salinity intrusion to increase in the eastern region also and will spread towards eastern direction but will be confined at the estuaries having low upstream freshwater discharge.
Year: 2018