Influence of Super Cyclone “Amphan” in the Indian Subcontinent amid COVID-19 Pandemic

Abstract

Tropical cyclone “Amphan” developed as a super cyclone on 19 May 2020 and caused severe impact on the landmass with very high torrential precipitation (>250 mm day ⁻¹), and extremely high wind speed (>150 km h ⁻¹) after landfall on 20 May 2020. The tropical cyclone Amphan largely affected agricultural land (78.2%) and forest, including mangroves (10.8%) in eastern India and Bangladesh. The built-up area over the trajectory of the cyclone and its proximity, including eastern parts of the Kolkata metropolitan area, was considerably affected by the cyclone due to the high population density and poor structural and community planning. Although the regions with close proximities to cyclones’ trajectory (2033 km ² area under <2 km proximity) were affected severely, the presence of mangrove forest in Sundarban substantially reduced the magnitude of the tropical cyclone. A considerable decrease (~30%) in aerosol optical depth (AOD) in April–May 2020 as compared to that in 2019 is considered one of the major causes of the development of the warm pool and cyclogenesis in the Bay of Bengal. The number of COVID-19 cases increased by ~70% in the post-cyclonic period (29 May 2020) compared to that in the pre-cyclonic period (19 May 2020) illustrating the impact of the cyclonic hazard.