Tauktae : A fallout of warming Arabian Sea region

With climate change triggering extreme weather events in quicker succession than ever before, scientists view the very severe Tauktae (pronounced Tau’ te) cyclonic storm a fallout of ocean warming and also an indication of future calamituous events.

A record eight cyclones - five in the quieter Arabian Sea and three in the usually raging Bay of Bengal - whipped up storms in the sub-continent during 2019. The trend continued in 2020 as five of these devastating wind-driven phenomena ripped through sea and land, driving home the grim reality.

“More and more number of severe cyclonic storms are forming in the Arabian sea due to the unusual warming of the western equatorial Indian Ocean and southern Arabian Sea,” M R Ramesh Kumar, a meteorologist and retired chief scientist of the National Institute of Oceanography said.

A recent study by NIO scientists has clearly indicated that this region will heat up in the near future, as indicated by predictions of several ocean atmospheric-coupled models.

The study published in the journal Climate Dynamics indicated that Coupled Model Intercomparison Project (CMIP5) models project an ‘inhomogeneous anthropogenic’ (meaning, uncharesteristic environmental pollution originating from human activity) surface warming of the Indian Ocean by 2099 with “strongest warming in the Arabian Sea and Western equatorial Indian Ocean”.

Previous studies have warned that this “Indian Ocean Dipole-like” warming pattern could yield more cyclones in the Arabian Sea. The study further showed that the warming of the Arabian Sea warming will be more than the Bay of Bengal in 80% of the model.

Last year, in what was categorised as the very severe cyclonic storm, Nisarga wreaked havoc in Goa and other places and had formed in late May. It reached its peak in June boosting the onset of southwest monsoon. Tauktae this year sprung up even earlier.

During the past 130 years there were 91 cyclones which formed during May - 63 in the Bay of Bengal and 28 in the Arabian Sea, Kumar said. “The last super cyclone in May 2020 was Amphan, but it had formed in Bay of Bengal on May 1 and dissipated on May 21.”

The last two cyclones in the Arabian Sea were in May 2018, one was headed for the Gulf of Aden and Cycone Mekunu made landfall near Oman which was the strongest storm since 1959. The oceanic region nearer to the Indian subcontinent is already the warmer one. “In the global ocean scenario this region will be the warmest in future too, giving rise to more and more cyclonic storms,” Kumar said.

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