Hurricanes
Hurricane is a storm system characterized by a low pressure center and numerous thunderstorms that produce strong winds and heavy rain. This tropical storm strengthens when water from the ocean is released . They are fueled by different heat mechanism then other cyclonic windstorms. The term "tropical" refers to both of the geographic origin. The term "cyclone" refers to storms with counterclockwise rotation. Hurricanes develop over warm bodies of water, and lose their strengthen if they move over land. As a result, tropical cyclones help maintain equilibrium in the earths troposphere. Heat is distributed vertically around the center of the storms.
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Center and eye
If the center is strong enough it will develop an eye. It is normally circular in shape, and can range in size. A "eye wall" is a circle of strong thunderstorms that surround the eye; here is where the highest wind speeds are found. Heave wind damage occurs where a tropical cyclones eye wall passes over land. eye wall replacement cycles occur naturally in intense tropical cyclones. Rain bands can organize into an outer ring of thunderstorms that move inward and robs the inner eye wall of its moisture and angular momentum. At the end of the cyclone the outer eye wall replaces the inner one completely. When the replacement cycle finishes the storm can be this same or it can be stronger. The storm may strengthen as it builds a new outer ring for the next replacement.

Mechanics
A hurricane can be visualized as a giant vertical heat engine support by mechanics driven by physical forces such as the rotation and gravity in earth. Another way tropical cyclones can be viewed is as a special type of mesosphere convective complex, which continues to develop over a vast source of relative warmth and moisture. Condensation leads to higher wind speed as tiny fraction of the released energy is converted into mechanical energy, the faster winds and lower pressure associated with them in turn cause increased surface evaporation and even more condensation. Released energy drives updrafts that increases the height of the storm cloud. When a hurricane passes over land it is cut off from its heat source and the strength goes down. Cooling is primarily caused by wind driven mixing from water deep in the ocean and the surface water.

Deadliest hurricanes
The deadliest hurricane was in Bhola cyclone. 1970 Bhola cyclone struck East Pakistan and West India on November 12, 1970. The Bhola cyclone was the deadliest cyclone in the history of time. Up to 500,000 lost their lives in this hurricane. The third deadliest cyclone was Calcutta cyclone on October 7, 1737. It struck the city of Calcutta in India. For the longest time people said they thought it was a earthquake, but latter came to the conclusion it was a hurricane.Calcutta destroyed nearly every building, and killed 3,000 of the cities inhabitants. This hurricane killed over 300,000 people.

Effects
Tropical cyclones stir up water leaving a cool wind behind them. On land the strong winds damage or destroy many objects, turning loose debris into deadly flying projectiles. Depending on the sea level that is how deadly the hurricane can be. Over the years hurricanes have been responsible for the deaths of about 1.9 million people all over the world. Although hurricanes have killed millions of people they bring much needed precipitation to dry regions. They also maintain the global heat balance.



What is a hurricane?
A hurricane is a violent tropical storm. They usually start in the west Caribbean or west Africa. As they move over warm water they are fueled. When air goes up to the storm it spirals upward. They can only be stopped when hit land or go over cooler water.


Hurricane terms
Tropical depression clouds and thunderstorms with a circulation and maximum winds. Tropical storm strong thunderstorms with circulation and maximum winds. The eye is in the center of the hurricane. eye wall where most rainfall and damaging winds are found. Tornadoes rotating clouds that touch the ground. A tornado watch means tornadoes are possible int the area. Tornado warning when tornadoes a spotted around your area. tropical disturbance a bunch of thunderstorms.


Other info on hurricanes
At first hurricanes are called a tropical disturbance. When the wind reaches 20 to 35 miles per hour it is called a tropical depression. It becomes a tropical storm when the wind speed reaches 35 to 60 miles per hour. When wind speed is 75 miles per hour of greater it becomes a hurricane. Around 90 percent of deaths occur when hurricanes land.


Pictures and videos


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http://en.wikipedia.org/wiki/Hurricanes

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