Context: The first cyclone of 2021 may be here, and quite a storm it can be. Cyclone Tauktae is likely to form May 16, 2021 in Arabian Sea. The system must be watched closely for rapid intensification, which can make predictions tough.
Background

• The frequency and intensity of cyclones in the Arabian Sea have increased in recent years. This is due to the rapid warming of the Arabian Sea because of climate change. 
• Cyclones like Fani and Amphan have intensified from a weak to severe status in less than 24 hours due to ocean warming.
• But this scenario is changing in a quick and uncertain way due to unusual warming of the Arabian Sea which itself could be a consequence of global warming resulting from the emissions of greenhouse gases from human activities.

About Cyclone Tauktae

• Tauktae is a name given by Myanmar and it means a highly vocal gecko. 
• The storm may intensify into a depression by May 15 and into a cyclone on May 16. 
• The cyclone may intensify and move towards the coasts of Gujarat and adjoining Pakistan.

Impact

• It may make landfall in Gujarat by the evening of May 18. 
• Coastal Kerala, Karnataka, Goa and Maharashtra will experience heavy rainfall from May 14.

Arabian Sea Cyclones

• Cyclonic activity is comparatively less intense in the Arabian sea, as compared to the Bay of Bengal, where high-intensity severe cyclones originate frequently.
• In the last 120 years, just about 14% of all cyclonic storms, and 23% of severe cyclones, around India have occurred in the Arabian Sea.
• Arabian Sea cyclones are also relatively weak compared to those emerging in the Bay of Bengal.
• Gujarat coastline, where most of the cyclones emerging in the Arabian Sea are headed, is not very densely populated, ensures that the damage potential of the cyclones on the western coast is comparatively low.

Why is the Bay of Bengal More Prone to Cyclones?

• Temperature difference: The low-pressure system of cyclone need a continuous supply of heat energy and as the Bay of Bengal is warmer than the Arabian sea, it is able to provide the heat energy needed to sustain the low-pressure system.

Sea surface temperatures and humidity: both directly correlate with chances of cyclone formation.

• The Bay of Bengal receives higher rainfall and constant inflow of fresh water from the Ganga and Brahmaputra rivers.
• This means that the Bay’s surface water keeps getting refreshed, making it impossible for the warm water to mix with the cooler water below, making it ideal for depression.

On the other hand, the Arabian Sea receives stronger winds that help dissipate the heat, and the lack of constant fresh water supply helps the warm water mix with the cool water, reducing the temperature.

• Absence of large landmass between the Pacific and the Bay, allows cyclonic winds to easily move into the Bay of Bengal.
• Cyclones from Pacific ocean: low-pressure system originating from the Pacific ocean also travel towards the left to the Bay of Bengal.

By: Shubham Tiwari