About Cyclone: Classification of cyclones

Cyclone

Mumbai hasn’t seen a cyclone for 129 years. Cyclone Nisarga is going to raise hell in the city. It will bring down to its knees the system that has made the island city what it is today, and inundate it with destruction and death. After a gap of 129 years, another super cyclone is likely to form over the Bay of Bengal creating havoc in south India and extreme weather conditions in Mumbai.

Classification of cyclones

Cyclones are classified as extra tropical cyclones (also called temperate cyclones); and tropical cyclones.

1. Tropical cyclones: Tropical cyclones develop in the region between the Tropics of Capricorn and Cancer. They are large-scale weather systems developing over tropical or subtropical waters, where they get organized into surface wind circulation.
2. Extra Tropical cyclones: Extra tropical cyclones occur in temperate zones and high latitude regions, though they are known to originate in the Polar Regions.

Formation and Development of Cyclones

Tropical cyclones are formed only over warm ocean waters near the equator. When warm, moist air over the ocean rises upward from near the surface, a cyclone is formed.

When the air rises up and away from the ocean surface, it creates an area of lower air pressure below. It causes the air from surrounding areas with higher pressure to move towards the low-pressure area which further leads to warming up of the air and causes it to rise above.

As the warm, moist air rises and cools the water in the air forms clouds. The complete system of clouds and wind spins and grows, along with the ocean's heat and water evaporating from the ocean surface.

As the wind system rotates with increasing speed, an eye gets formed in the middle. The centre of a cyclone is very calm and clear with very low air pressure. The difference of temperature between the warm, rising and the cooler environment causes the air to rise and become buoyant.

Various Categories of Cyclone

Cyclones are categorized on the basis of the strength of the winds.

Some Major Cyclones that hit Indian coasts

Cyclone Nivar: Cyclone Nivar got built over the Bay of Bengal and heading towards the southern states and Union territory (UT) of Andhra Pradesh, Tamil Nadu and Puducherry. It is expected to make landfall on Wednesday causing heavy rainfalls.

Cyclone Amphan: It had hit Indian coasts in 2020, leading to major damage in West Bengal, along with the bordering areas.

Cyclone Nisarga: It was a severe cyclone which had hit the Indian subcontinent in less than 14 days of Amphan. It led to huge destruction in Maharashtra, causing a large number of fatalities. Cyclone Nisarga formed on June 1 and dissipated on June 4, becoming the strongest tropical cyclone to strike Maharashtra since 1891.

Cyclone Fani: It was a huge cyclone which caused major damage in Odisha, being the strongest tropical cyclone to hit the state since 1999. Odisha faced maximum vandalization among the states hit by the cyclone.

Cyclone Bulbul: It was another severe cyclone which impacted both West Bengal and Bangladesh. Bulbul was a tropical cyclone which began forming on November 5, 2019, and dissipated on November 11 and claimed 41 lives. Neighbouring countries like Myanmar and Thailand were also affected.

Cyclone Vayu: It was the strongest cyclone to hit the Saurashtra region of Gujarat since 1998. It was formed on June 10, 2019, dissipated on June 17 and claimed 8 lives in June 2019. Vayu is taken from the Sanskrit and Hindi word 'Vayu' meaning wind. It had affected more than 6.6 million lives in the northwestern parts of the country.

Cyclone Maha: It had impacted the states of Maharashtra, Gujarat and Kerala. It was formed on October 30, 2019, dissipated on November 7 as a severe cyclonic storm.