World Environment Day observed with plantation of saplings at University of Kalyani
The eastern Indian sub-continent exposed to an extremely severe cyclonic storm (as per IMD Scale) or Category 2 tropical cyclonic storm (as per SSWS) called "Amphan" formed at North Indian Basin during May 16 (formed) to 21st May (dissipated), 2020.
Amphan made landfall with a sustained wind speed of 165 km per hour at the ashore near the border of West Bengal and Bangladesh on May 20, at 4 p.m. The winds pushed up a 5-meter storm surge that flooded the entire coastal areas including the Sunderbans, a zone of precious mangrove forests and critical habitat for tiger and gharial crocodile, in the delta spanning the India - Bangladesh coastal border.
After the landfall, Amphan moved north-northeastwards over the land, and battered the entire southern regions of West Bengal. It destroyed lakhs of mud houses and buildings., uprooted trees and crops ., downed power lines ., and severely damaged roads and coastal sea dikes. Amphan also slammed the Odisha and Andaman Islands of India., and Sri Lanka, Bangladesh and Bhutan. It killed 86 people in West Bengal., and crippled the lives and livelihoods of about 8 crore people of West Bengal including the marginal farmers and indigenous fishing communities.
Unprecedented sea surface warming at Bay of Bengal was the main climatic reason for the formation of Amphan. It was found that just before the formation of Amphan, the surface temperature at the region in Bay of Bengal where Amphan was formed was increased steeply to 36 degrees Celsius from the average critical temperature of 26 degrees Celsius, the minimum temperature required for the formation of tropical cyclone over the sea surface.
The cyclonic storm "Nisarga" that slammed the northern Maharashtra and southern Gujarat on June 3, 2020 with a wind speed of 105 km per hour has also been formed unprecedented over the surface of East- Central Arabian Sea due to sea surface warming.
Seasonal increase in the atmospheric concentration of greenhouse gases (GHGs) over the North Indian Basin is the main reason for sea surface warming. Human activities like severe deforestation and fossil fuel burning at the region of Indian Subcontinent are the key reasons for increase in concentration of GHGs in the atmosphere. Tropical climate change could be prevented by adopting some mitigation measures like promotion of afforestation and reforestation. and prevention of deforestation and fossil fuel burning in the Indian sub-continent.
Professor Dr. Goutam Paul: Pro-Vice- Chancellor, Kalyani University