UPSC PRELIMS 2019 : Cyclonic storm Vayu

Cyclonic storm Vayu

Topic : Cyclonic storm Vayu

Topic in Syllabus: Indian Geography

 

About Cyclone Vayu:

Cyclonic storm Vayu

‘Vayu’ was the second most intense cyclonic storm to have formed near the Indian coast after Cyclone Fani, which left a trail of destruction in Odisha on the eastern coast in early May. Fani was the longest-lasting cyclone over the Bay of Bengal, hovering for over 11 days.

 

Cyclone:

  • Cyclones are sustained by very strong low-pressure areas at their core. Winds in surrounding areas are forced to rush towards these low-pressure areas.
  • Similar low-pressure areas, when they develop near or over land, are instrumental in pulling the monsoon winds over the country as well.
  • But right now, the low-pressure area at the center of the cyclone is far more powerful than any local system that can pull the monsoon winds moving northeast.
  • 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.

 

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 waterfrom 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.
  • 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.

 

Sample Question:

Match the colours with different Cyclonic Alerts

  1. Yellow: Be Updated
  2. Orange: Be prepared
  3. Red: Take action
  4. Green: No warning

Choose the Correct Answer Below

a). 1 and 3

b). 2 and 3

c). 1 and 4

d). All

Answer: d