Super Cyclone Amphan Is Set to Hit India and Bangladesh

News:Cyclone Amphan has intensified into a super cyclonic storm and is expected to make landfall between West Bengal and Bangladesh close to Sundarbans.

Facts:

Cyclone Amphan:

  • Cyclone Amphan is a tropical cyclone formed over Bay of Bengal that has turned into a super cyclonic storm.
  • The Cyclone Amphan is also the strongest storm to have formed in the Bay of Bengal since the super cyclone of 1999 that ravaged Paradip in Odisha.

Why does the Bay of Bengal receive higher Cyclones compared to Arabian Sea?

  • Higher Rainfall: Bay of Bengal receives higher rainfall which provides required humidity for cyclone formation.
  • Temperature: Bay of Bengal is hotter than Arabian sea.Hot water temperature is the basic criteria for the development & intensification of cyclones.
  • Location:The typhoons originating in the Pacific Ocean too influence the cyclones in BOB not the case in Arabian Sea.
  • Constant Inflow of Fresh Water: The inflow from the Ganga and Brahmaputra rivers makes it impossible for the warm water to mix with the cooler water making it ideal for a cyclonic depression.
  • Sluggish Winds:It keeps temperatures relatively high of about 28 degrees around the year.

Reasons responsible for intensification of Cyclones in Bay of Bengal:

  • In 2020, the Bay of Bengal has observed record summer temperatures due to global warming from fossil fuel emissions that have been heating up oceans.
  • However,such unusual warming around India is no longer restricted to just the BoB but also the Arabian Sea and the Indian Ocean.It makes storm prediction less reliable as well as disrupting monsoon patterns.
  • Further, reduced particulate matter emissions during the lockdown resulted in fewer aerosols such as black carbon that are known to reflect sunlight and heat away from the surface.

Classification of Cyclones:The criteria followed by Indian meteorological Department(IMD) to classify Cyclones in the Bay of Bengal and in the Arabian Sea are as under: