Cyclone Dana to hit Odisha, West Bengal: What is a cyclone and what are its types?

The cyclone is expected to bring airy rainfall successful astir places, and highly dense rainfall (≥ 21 cm) astatine isolated places implicit Baleswar, Mayurbhanj, Bhadrak, Kendrapara, Jagatsingpur Kendujhar, Jajpur, Cuttack and Dhenkanal, Khorda and Puri districts of Odisha connected 24th & 25th October. Isolated places implicit South & North 24 Parganas, East & West Medinipur, Jhargram, Howrah, Hooghly, Kolkata and Bankura districts of Gangetic West Bengal volition besides apt witnesser dense rainfall during the aforesaid period.

Cyclone Dana, expected to make upwind speeds of 100-110 kmph and gusts astatine 120 kmph, is simply a tropical cyclone. The National Disaster Management Authority (NDMA) classifies cyclones broadly into 2 categories: extratropical cyclones and tropical cyclones.

Here is simply a look astatine what a cyclone is and its types.

What is simply a cyclone?

A cyclone is simply a large-scale strategy of aerial that rotates astir the centre of a low-pressure area. It is usually accompanied by convulsive storms and atrocious weather. A cyclone is characterised by inward spiralling winds that rotate anticlockwise successful the Northern Hemisphere and clockwise successful the Southern Hemisphere, according to the NDMA.

What are extratropical cyclones?

Also known arsenic mid-latitude cyclones, extratropical cyclones hap extracurricular of the tropics. They person “cold aerial astatine their core, and deduce their vigor from the merchandise of imaginable vigor erstwhile acold and lukewarm aerial masses interact”, according to the US National Oceanic and Atmospheric Administration (NOAA). It added that specified cyclones ever person 1 oregon much fronts — a upwind strategy that is the bound betwixt 2 antithetic types of aerial masses. One is represented by lukewarm aerial and the different by acold aerial — connected to them, and tin hap implicit onshore oregon ocean.

What are tropical cyclones?

Tropical cyclones are those which make successful the regions betwixt the Tropics of Capricorn and Cancer. They are the astir devastating storms connected Earth. Such cyclones make erstwhile “thunderstorm enactment starts gathering adjacent to the centre of circulation, and the strongest winds and rainfall are nary longer successful a set acold from the centre,” NOAA noted. The halfway of the tempest turns warm, and the cyclone gets astir of its vigor from the “latent heat” released erstwhile h2o vapour that has evaporated from lukewarm water waters condenses into liquid water, the bureau added. Moreover, lukewarm fronts oregon acold fronts aren’t associated with tropical cyclones.

Tropical cyclones person antithetic names depending connected their determination and strength. They are known arsenic hurricanes successful the Caribbean Sea, the Gulf of Mexico, the North Atlantic Ocean, and the eastbound and cardinal North Pacific Ocean. In the occidental North Pacific, they are called typhoons.