© The Indian Express Pvt Ltd
Tags:
Journalism of Courage
CYCLONE DANA IMD UPDATES: The Indian Meteorological Department said Wednesday (October 23) that Cyclone Dana will likely intensify into a severe cyclonic storm and make landfall in West Bengal and Odisha between Thursday night and Friday morning.
“Cyclone Dana moved at a speed of 18km/hr during the last six hours and lay over east-central Bay of Bengal. It is very likely to move northwestwards and intensify into a severe cyclonic storm over northwest Bay of Bengal by early morning of 24th and cross north Odisha and West Bengal coasts between Puri and Sagar Island close to Bhitarkanika-Dhamra (Odisha) during night of 24th to morning of 25th October, 2024 as a severe Cyclonic Storm with a wind speed of 100-110 kmph gusting 120 kmph,” the IMD wrote in a post on X.
The cyclone is expected to bring light rainfall in most places, and extremely heavy rainfall (≥ 21 cm) at isolated places over Baleswar, Mayurbhanj, Bhadrak, Kendrapara, Jagatsingpur Kendujhar, Jajpur, Cuttack and Dhenkanal, Khorda and Puri districts of Odisha on 24th & 25th October. Isolated places over South & North 24 Parganas, East & West Medinipur, Jhargram, Howrah, Hooghly, Kolkata and Bankura districts of Gangetic West Bengal will also likely witness heavy rainfall during the same period.
Cyclone Dana, expected to generate wind speeds of 100-110 kmph and gusts at 120 kmph, is a tropical cyclone. The National Disaster Management Authority (NDMA) classifies cyclones broadly into two categories: extratropical cyclones and tropical cyclones.
Here is a look at what a cyclone is and its types.
A cyclone is a large-scale system of air that rotates around the centre of a low-pressure area. It is usually accompanied by violent storms and bad weather. A cyclone is characterised by inward spiralling winds that rotate anticlockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere, according to the NDMA.
Also known as mid-latitude cyclones, extratropical cyclones occur outside of the tropics. They have “cold air at their core, and derive their energy from the release of potential energy when cold and warm air masses interact”, according to the US National Oceanic and Atmospheric Administration (NOAA). It added that such cyclones always have one or more fronts — a weather system that is the boundary between two different types of air masses. One is represented by warm air and the other by cold air — connected to them, and can occur over land or ocean.
Tropical cyclones are those which develop in the regions between the Tropics of Capricorn and Cancer. They are the most devastating storms on Earth. Such cyclones develop when “thunderstorm activity starts building close to the centre of circulation, and the strongest winds and rain are no longer in a band far from the centre,” NOAA noted. The core of the storm turns warm, and the cyclone gets most of its energy from the “latent heat” released when water vapour that has evaporated from warm ocean waters condenses into liquid water, the agency added. Moreover, warm fronts or cold fronts aren’t associated with tropical cyclones.
Tropical cyclones have different names depending on their location and strength. They are known as hurricanes in the Caribbean Sea, the Gulf of Mexico, the North Atlantic Ocean, and the eastern and central North Pacific Ocean. In the western North Pacific, they are called typhoons.
