A tropical cyclone is a storm system that is characterized by a low-pressure center that produces strong winds and heavy rain. A tropical cyclone feeds on heat released by the condensation of moist air. The latent heat gets converted into kinetic energy and feeds the strong winds emerging out of it. Because of its warm center, it’s often called a warm core storm system. Cyclonic storms have a counterclockwise rotation in the Northern Hemisphere and clockwise rotation in the Southern Hemisphere. Developed over warm water bodies, like oceans and seas, they lose their strength once they move over land. Apart from ( their devastating nature, they help in the global atmospheric circulation mechanism by carrying heat and energy away from the tropics towards temperate latitudes.
Why are cyclones named?
Tropical cyclones are named to provide ease of communication between forecasters and the general public. Apart from this, they can often last a week or longer and the same basin can have more than one cyclone. Hence, assigning names reduces confusion about what storm is being described. The naming of cyclones started in the early 20th century when an Australian forecaster started naming cyclones after politicians he disliked. During World War II, American meteorologists started naming cyclones after their wives and girlfriends and all cyclones were christened with female names. In the early 50s, they were identified by the phonetic alphabet — Able, Baker, Charlie and so on. In 1953, the US Weather Bureau again switched to women’s names. Now, cyclones are given names that are contributed by member nations of the World Meteorological Organisation. The new names include those identified with men, women, flowers and so on. In the North Atlantic and Northeastern Pacific regions, feminine and masculine names are alternated in alphabetical order during a given season.
What is the process of naming cyclones?
The regional body responsible for monitoring tropical cyclones in a particular basin makes a list of cyclone names for that particular basin. There are five such bodies that keep 10 pre-designated lists of cyclone names. The names are proposed by the member countries. For instance, the names of cyclones in the northern Indian Ocean are contributed by Bangladesh, India, the Maldives, Myanmar, Oman, Pakistan, Sri Lanka, and Thailand. Different basins use different methods for naming cyclones. In the Caribbean Sea, the Gulf of Mexico and the North Atlantic there are six lists, each having 21 names. These lists are annually rotated. The names of exceptionally destructive storms are retired from the list and hence Katrina can never reappear. In the northern Indian Ocean, there is no yearly list.
What is the difference between hurricane, typhoon, and cyclone?
They are all tropical cyclones, but different basins use different nomenclature. Tropical cyclones are formed in eight basins — Northern Atlantic, Northeastern Pacific, North Central Pacific, Northwestern Pacific, Northern Indian Ocean, Southwestern Indian Ocean, South and Southwestern Pacific and Southeastern Indian Ocean. In the North Atlantic Ocean, Northwest Pacific Ocean east of the International Date Line and South Pacific Ocean, they are called hurricanes. Typhoon is the name given to a tropical cyclone formed in the Northwest Pacific Ocean west of the dateline. In the southwest Pacific Ocean and the southeast Indian Ocean, it’s called a severe tropical cyclone. Similarly, tropical cyclones in the north Indian Ocean and southwest Indian Ocean are called severe cyclonic storm and tropical cyclone, respectively.