Rapid assessment of flood inundation due to tropical cyclones in part of Sundarbans in Google Earth Engine environment

Abstract

Abstract Coastal West Bengal (especially Sundarbans) has been facing frequent tropical cyclones in recent years, causing enormous losses in agriculture and other resources. Amphan (20 May 2020) and Yaas (26 May 2021) are the two most significant cyclonic events in recent years. In the present study, we analyzed flooding conditions due to Amphan and Yaas in South 24 Parganas - a significant part of Indian Sundarbans. Sentinel-1 (S1) data along with other earth observation datasets and products, were integrated into the Google Earth Engine (GEE) environment to monitor the flooding conditions of the two cyclonic events. Cloud penetration capability and high spatial resolution of S1 data provide ample opportunity to detect flooding during cloudy conditions. The most inundation occurred in agricultural lands (92.7% for Amphan and 96.04% for Yaas), followed by other Land Use Land Cover (LULC) types in both cases. Block-level (smallest administrative unit) flood statistics have been generated for both events. Gosaba, Pathar Pratima, and Namkhana were most affected by these two cyclones.