Context: As per the India Meteorological Department (IMD) Cyclone Asna has formed over the Kutch coast in Gujarat and adjoining areas of Pakistan.

About Cyclone Asna

• This is the first cyclonic storm in the Arabian Sea in August since 1976. 

• The name Asna, which means “the one to be acknowledged or praised”, has been given by Pakistan. 

• It is an extraordinary meteorological event that has drawn significant attention due to its unusual origin and development. Unlike typical cyclones, which form over warm ocean waters, Asna’s journey began over the landmass of Rajasthan. 

• This cyclone transitioned from a land-based depression into a powerful system over the Arabian Sea, where it intensified rapidly. 

• Such an occurrence is not only geographically rare but also scientifically fascinating, as it defies the conventional patterns associated with cyclone formation and movement. 

• Between 1891 and 2023, only three cyclonic storms formed in the Arabian Sea in August (in 1976, 1964, and 1944).

• Origin of Cyclone Asna

• Cyclone Asna is considered geographically rare because it originated over land in Rajasthan, an area far from the typical oceanic origins of cyclones. The system then moved into the Arabian Sea, which generally sees fewer cyclones compared to the Bay of Bengal, particularly during the month of August.

• Formation of Cyclone Asna

• The formation of Cyclone Asna is scientifically intriguing due to its rare combination of factors. Initially, it was a deep depression triggered by a low-pressure system over Gujarat, which intensified over the Arabian Sea. 

• This event challenges the usual understanding of cyclone formation, which typically requires consistent warm sea surface temperatures and a stable oceanic environment.

• Role of Monsoon in the development of Cyclone Asna

• The monsoon played a crucial role in the development of Cyclone Asna. The low-pressure system associated with the monsoon over Gujarat contributed to the initial formation of the depression that eventually became Cyclone Asna. 

• This interaction between monsoon dynamics and cyclone formation is unusual, especially given the cyclone’s land-based origin.

• Conditions in the Arabian Sea that allowed Cyclone Asna to intensify

• The Arabian Sea provided the necessary conditions for Cyclone Asna to intensify, with sea surface temperatures above 27-28°C, which is critical for cyclone development. 

• These warm waters, combined with the existing low-pressure system, allowed Asna to evolve from a depression into a full-fledged cyclone.

• Impact

• Cyclone Asna had a significant impact on the regions along the Arabian Sea, particularly in Gujarat. The cyclone brought heavy rainfall, strong winds, and caused disruptions to coastal activities. Rescue operations were launched to save stranded fishermen, and multiple evacuations were carried out to protect residents in vulnerable areas.

Worldwide terminology

• Cyclones are given many names in different regions of the world – They are known as:

1. Typhoons in the China Sea and Pacific Ocean

2. Hurricanes in the West Indian islands in the Caribbean Sea and Atlantic Ocean

3. Tornados in the Guinea lands of West Africa and southern USA

4. Willy-willies in north-western Australia

5. Tropical cyclones in the Indian Ocean

High Pressure Area and Low Pressure Area

• In high-pressure systems, air descends toward the ground, resulting in stable atmospheric conditions.

• In low-pressure systems, air rises, leading to more unstable atmospheric conditions.

India Meteorological Department (IMD)

• It was established in 1875. 

• It is the principal government agency in all matters relating to meteorology and allied subjects.

• It is under the Ministry of Earth Sciences (MoES).