BHUBANESWAR: As Odisha braces for yet another cyclone, the spotlight is back on the factors that make the Bay of Bengal a breeding ground for intense tropical systems.
The state has recorded around 400 cyclonic events, including depression, cyclonic storms and severe cyclonic storms between 1890 and 2024, of which 293 were depressions and 107 cyclones impacting the economy and ecology.
The Bay of Bengal region is notorious for being one of the most cyclone-prone areas in the world. The frequent occurrence of cyclones can be attributed to the geographical location of the sea, tropical climate and warmer sea surface temperatures, experts said.
Associate professor in the School of Earth, Ocean and Climate Sciences at IIT-Bhubaneswar Sandeep Pattnaik said the initial disturbances are more in the Bay of Bengal region because it is adjacent to the North West Pacific.
“The cyclonic circulations (remnants of typhoons) formed in the North West Pacific cross over to Bay of Bengal where the conducive conditions help the systems amplify further. Cyclones in the region are more common during the pre and post-monsoon seasons due to the changing weather systems and pressure zones that create favourable conditions for intensification,” he said.
Besides the tropical climate, Pattnaik said, relatively warmer sea surface temperatures in the Bay of Bengal, particularly from April to November, fuel the intensity of cyclones, making them more frequent and stronger in this region.
Odisha has a long and challenging history with cyclones, dating back decades. Its location along the eastern coast makes the state one of the world’s six most cyclone-prone places with the highest risk in terms of cyclone landfall.
According to a study by researchers from four universities of the state, though the frequency of depression and cyclonic storm is declining steadily in last four decades, the number of severe storms is rising.
The frequency of severe storms that averaged about seven per cent between 1890 and 1929 though dropped to an average of five per cent during 1930-1969, the period from 2010 to 2020 had the highest contribution of 20 per cent severe storms in coastal Odisha.
One of the researchers and professor of Geography at FM University Manoranjan Mishra said Odisha’s vulnerability to cyclones is an unfortunate reality of its geography. “Though the state’s coastline constitutes only 17 per cent of the Indian east coast, it has seen around 35 per cent cyclonic and severe cyclonic storms that have traversed the east coast. The frequency of depression may have reduced, but the intensification has increased,” he added.