New Delhi: The maiden cyclonic storm of the season, Cyclone Mocha, has formed over the southeast Bay of Bengal. Atmospheric conditions are very conducive for Cyclone Mocha to intensify further.
The reason, say, experts, is a warmer ocean that is fuel for ever more powerful storms, threatening the region with violent winds, flooding, and landslides that could potentially affect hundreds of thousands of people.
The Indian Ocean region, including the Arabian Sea and the Bay of Bengal, is of particular concern because of the high population density along its coastlines.
According to the India Meteorology Department, Mocha is likely to cross southeast Bangladesh and north Myanmar coasts between Cox’s Bazar in Bangladesh and Kyaukpyu in Myanmar by noon of May 14 as a very severe cyclonic storm.
UN agencies say nearly one million Rohingya refugees in Cox’s Bazar camps are preparing for the worst. In 2022, they escaped devastation from the Bay of Bengal cyclone Sitrang, which nonetheless killed 35 people, displaced over 20,000, and caused over $35 million in damages in other parts of the country.
Extreme weather hazards will occur more frequently due to climate change in the years ahead, the International Organization for Migration (IOM) warned.
“The linkages between climate change, migration, and displacement are increasingly pressing worldwide,” it said, calling on governments to implement sustainable climate adaptation, preparedness, and disaster risk reduction measures to avert, mitigate, and address displacement linked to climate disasters and strengthen people’s resilience.
Researchers and scientists have been blaming increasing global mean temperature behind the changes in the cyclogenesis, particularly over the Indian Ocean.
Citing the Intergovernmental Panel on Climate Change’s (IPCC) Special Report on Ocean and Cryosphere in a Changing Climate, climate change is taking place due to long-lived greenhouse gases in the atmosphere that have increased the radiative forcing of the climate system.
Radiative forcing is what happens when the amount of energy that enters the earth’s atmosphere is different from the amount of energy that leaves it.
Energy travels in the form of solar radiation entering the atmosphere from the sun, and infrared radiation exiting as heat. If more radiation is entering Earth than leaving, as is happening today, then the atmosphere will warm up because the difference in energy can force changes in the Earth’s climate.
A consequence of this energy imbalance at the top of the atmosphere, of which about 92 per cent goes into the ocean, is the increasing Ocean Heat Content.
Primary indicators of a changing climate include an increase in the global mean surface temperature, sea level, and Ocean Heat Content.
As long as oceans are warm and winds are favourable, cyclones will retain their intensity for a longer period, explains Roxy Mathew Koll, Climate Scientist with the Indian Institute of Tropical Meteorology and Lead IPCC Author.
“The Bay of Bengal has been riding on the wave of global warming during the past few decades. Temperatures have been between 30-32 degrees Celsius in the Bay of Bengal. These high temperatures play a very important role in the intensification of cyclonic storms as they infuse more convection. This kind of rapid intensification has become frequent recently both in the Arabian Sea as well as in the Bay of Bengal.”
Sounding a warning note, MM Ali, Meteorologist and Oceanologist with Andhra Pradesh State Disaster Management Authority said the sea surface temperatures are increasing.
“The mechanism behind the formation of cyclones does not change but weather conditions are changing. Cyclones have been intensifying at a faster pace in the recent past. The reason is not just an increase in the sea surface temperatures but also rising ocean heat content.
“Earlier the system used to take two-three days before forming into a tropical storm but nowadays it changes from a depression into a cyclonic storm in just a day.”
According to the IPCC, at the ocean’s surface the temperature has, on average, increased by 0.88°C (0.68°C to 1.01°C) degree Celsius between 1850-1900 and 2011-2020 with 0.60 (0.44 to 0.74) degree Celsius of this warming has occurred since 1980.
(IANS)
