Cyclones that develop in between the tropics i.e. between 23°30′ N and 23°30′ S latitude are called tropical cyclones. The phenomenon of tropical cyclone is known by various names in different parts of the world. Some of the popular names are:
| Country | Name |
|---|---|
| Australia | Willy Willy |
| China | Typhoon |
| India | Cyclones |
| Japan | Taifu |
| Phillippines | Baguio |
| USA | Hurricane |
Cyclones are centers of low pressure that are surrounded by closed isobars. The pressure is extremely low at the center and increases outwards. Thus the wind flows from the rim to the central core. Due to the Coriolis Effect, the winds move in anticlockwise in the northern hemisphere and in a clockwise direction in southern hemisphere. From the locational point of view cyclones are classified as:
- Tropical Cyclone (originating between the tropics)
- Extra-Tropical Cyclones (originating beyond the tropics)
The word “cyclone” is derived from the Greek words “kuklos” and “kukloun” meaning “circle” and “to rotate” respectively. Another possibility is that it may have been derived from Egyptian word “Cykline” meaning “to spin”.
The word “hurricane” derived its name from Caribbean Amerindian storm God “Huracan”. Another word for cyclone popular in the Asian countries is typhoon. It is believed that it has originated from Urdu, Persian or Arabic word “tufan” or Greek word “tuphon”.
Hurricane Gustav & Tropical Storm Hanna