Tropical cyclones occur when a complex set of atmospheric conditions combine and advance to produce violent weather.
The generic term "tropical cyclone" encompasses hurricanes, typhoons, tropical storms, depressions and disturbances. These disruptive low-pressure weather systems that occur in moist tropical air have a measurable wind circulation and develop over subtropical and tropical bodies of water. They are prone to form in the Pacific Ocean, the Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico.
Every few days strong thunderstorms gather strength, and boom through the atmosphere above the water as tropical waves of low pressure travel with winds from the west. The low pressure draws moist air off of the surface of the sea, which cause winds to begin spiraling at the core of the low pressure.
When warm air gets close to the core it quickly rises, forming condensation that results in rain. At this point, large forces of heat are released, causing winds to gain strength, and the storm to become self-propelled. If a tropical cyclone progresses to hurricane strength, an eye will usually be created.
What's the Difference?
Cyclones can develop in various parts of the world, but there is one key characteristic which separates them from tropical cyclones. The tropical cyclone is a "warm core" system, which means it is warmer in the center than the winds raging around it. This he characteristic that separates tropical cyclones from other cyclonic systems is that any height in the atmosphere, the center of a tropical cyclone will be warmer than its surrounds; a phenomenon called "warm core" storm systems.
Tropical Cyclone Umbrella
The term "tropical cyclone" covers any of the four stages of a hurricane's life span: Tropical disturbance, tropical depression, tropical storm, hurricane.
* A tropical disturbance is defined as an isolated tropical cloud, shower or thunderstorm system which lasts for at least 24 hours. Another type of tropical disturbance is the phenomenon of tropical waves, which are low pressure forces that typically flow east to west.
* A tropical depression occurs when a disturbance prompts winds to rotate around a low pressure center.
* A tropical storm is a powerful force, with winds raging between 39 to 73 miles-per-hour. When a tropical cyclone reaches this level, it is given a name by the National Hurricane Center.
* A hurricane is the most powerful form of tropical cyclone. Its destructive winds can range anywhere between 74 m.p.h. to well over 100 m.p.h. The severity of these storms is numerically categorized on a 1-to-5 scale based on damage potential, wind speed and barometric pressure.
You have just read the logical explanation as to why tropical cyclones occur. Another, non-scientific way to justify the constant existence of these storms is to speculate that even Mother Earth needs to blow off some steam every now and then.