Tuesday, February 19, 2008

Cyclone

A tropical cyclone is a meteorological term for a storm system characterized by a low pressure system center and thunderstorms that produces tough wind and flooding rain. A tropical cyclone feeds on the heat released when tacky air rises and the water spray it contains condenses. They are fueled by a different heat machinery than other cyclonic windstorms such as nor'easters, European windstorms, and polar lows, leading to their classification as "warm core" storm systems.

The term "tropical" refers to both the geographic derivation of these systems, which form almost exclusively in humid regions of the globe, and their formation in Maritime Tropical air masses. The term "cyclone" refers to such storms' cyclonic nature, with counterclockwise rotation in the Northern Hemisphere and clockwise rotation in the Southern Hemisphere. Depending on their location and strength, tropical cyclones are referred to by various other names, such as hurricane, typhoon, tropical storm, cyclonic storm, and tropical misery.

While tropical cyclones can produce extremely powerful winds and heavy rain, they are also able to produce high waves and damaging storm surge. They develop over large bodies of warm water, and lose their strength if they move over land. This is the reason coastal regions can receive significant damage from a tropical cyclone, while inland regions are relatively safe from receiving strong winds. Heavy rains, however, can produce significant flooding inland, and storm surges can produce broad coastal flooding up to 25 mi (40 km) from the coastline. Although their effects on human populations can be devastating, tropical cyclones can also relieve drought conditions. They also carry heat and energy away from the tropics and transport it towards temperate latitudes, which makes them an important part of the global atmospheric circulation method. As a result, tropical cyclones help to maintain symmetry in the Earth's troposphere, and to maintain a relatively stable and warm temperature worldwide.

Many tropical cyclones develop when the distinctive conditions around a weak disturbance in the atmosphere are favorable. Others form when other types of cyclones acquire tropical characteristics. Tropical systems are then moved by steering winds in the troposphere; if the conditions remain favorable, the tropical disturbance intensifies, and can even develop an eye. On the other end of the variety, if the conditions around the system depreciate or the tropical cyclone makes landfall, the system weakens and eventually dissipates.