From UPSC perspective, the following things are important :
Prelims level : Arabian Sea Cyclones
Mains level : Tropical Cyclones in India and thier aftermath
- Just over a month after the powerful cyclone Fani devastated large areas of Odisha, another cyclone is headed towards India, this time towards the Gujarat coast.
Arabian Sea cyclones
- Though cyclones are common in the June, very few of them originate in the Arabian Sea. Most of them are found in the Bay of Bengal.
- In the last 120 years for which records are available, 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.
- This, along with the fact that the Gujarat coastline, which is where most of the cyclones emerging in the Arabian Sea are headed, is not very densely populated.
- This ensures that the damage potential of the cyclones on the western coast is comparatively low.
About Cyclone Vayu
- Cyclone Vayu is a deep depression positioned around 250 km northwest of Aminidivi island in Lakshadweep and about 750 km southwest of Mumbai.
- It is likely to generate winds of speed 110-120 km per hour. In contrast, winds associated with Fani had speeds of about 220 km per hour.
- Vayu at its most powerful stage would only be categorised as a “severe cyclonic storm”, while Fani was an “extremely severe cyclonic storm”
- It has almost satisfied the conditions for classification as a “super cyclone”.
Major Impact: It halts Monsoon
- 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.
- Vayu is likely to halt the northward progression of the monsoon for a few days.
- The cyclone is expected to interfere with normal progression, by sucking all the moisture from the monsoon winds towards itself.
- 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 centre of the cyclone is far more powerful than any local system that can pull the monsoon winds moving northeast.
- What this means is that the places where the monsoon has already reached would continue to get rain, mainly along the western coastline, but other areas would have to wait a little longer.