What is the source of energy of a developing typhoon?

All tropical cyclones form as a result of heat energy from the sun, which warms the surface waters in the tropical zone near Earth's equator.

Normally, warm ocean water evaporates, rises into the atmosphere, cools off to form clouds, and eventually falls back in the form of rain. However, if the atmosphere has just the right degree of instability, the rising warm water vapor will start rotating due to a geophysical phenomenon called the Coreolis Effect., and a cyclone will begin to form. Eventually the rotation can reach speeds of over 100 mph, although there is no wind at all in the very center of the cyclone called the Eye of the storm.

Every minute, a tropical cyclone can absorb and release as much energy as that from a large atomic fission bomb. A cyclone will continue to grow in strength as long as it has a supply of warm water to provide it with energy, but it will quickly dissipate when the energy source disappears (such as when the cyclone moves over land or enters a region of cooler water).

Cyclones are given several different names depending on their strength and locaction. Tropical depressions, tropical storms, typhoons and hurricanes are all cyclones.