Weakening of Tej in Arabian Sea might have strengthened Hamoon in Bay of Bengal: IMD Expert

Subject :Geography

Section: Physical geography

Context:

Two cyclonic storms ‘Tej’ and ‘Hamoon’ have developed over Arabian Sea and Bay of Bengal simultaneously.

Details:

The weakening of Cyclone Tej in the Arabian Sea might have strengthened its counterpart Cyclone Hamoon across Peninsular India in the Bay of Bengal.
Previously in 2018, Cyclones Luban and Titli formed over the Arabian Sea and Bay of Bengal respectively.
In a twin cyclonic system often one gets stronger. In this case, Tej was the stronger one. But as it has already made landfall, shifted and is gradually weakening. Now Hamoon is set to become a ‘very severe cyclonic storm’, maybe due to the sea surface temperature of the region where it is now located is more than the earlier position.
As a system moves away from the coast; the influx of warm air gets reduced. Consequently, the system gets stronger.

The FUJIWHARA effect:

Identified by SakuheiFujiwhara, a Japanese meteorologist.
The FUJIWHARA effect is any interaction between tropical storms formed around the same time in the same ocean region with their centres or eyes at a distance of less than 1,400 km, with intensity that could vary between a depression (wind speed under 63 km per hour) and a super typhoon (wind speed over 209 km per hour).
The interaction could lead to changes in the track and intensity of either or both storm systems.
In rare cases, the two systems could merge, especially when they are of similar size and intensity, to form a bigger storm.
There are five different ways in which the Fujiwhara effect can take place:

The first is elastic interaction in which only the direction of motion of the storms changes and is the most common case.
- These are also the cases that are difficult to assess and need closer examination.
The second is partial straining out in which a part of the smaller storm is lost to the atmosphere.
The third is complete straining out in which the smaller storm is completely lost to the atmosphere.
- The straining out does not happen for storms of equal strength.
The fourth type is a partial merger in which the smaller storm merges into the bigger one.
The fifth is a complete merger which takes place between two storms of similar strength.

Source: DownToEarth