At the end of this lesson students should be able to:
• Define the term “hurricane”
• List three categories of a hurricane.
• Tell how a hurricane is formed
• State how a hurricane is measured and name a scale which is used.
• Define the structure of a hurricane
• Explain the effects and impacts on the environment and the society.
Definition
A Hurricane is a severe storm with a violent wind. A hurricane is a type of tropical cyclone, the general term for all circulating weather systems counter clockwise in the Northern Hemisphere over tropical waters. When a hurricane is formed over the western Pacific, these hurricanes are called “typhoons,” and similar storms in the Indian Ocean are called “cyclones”.
There are three classifications of Tropical cyclones:
Tropical Depression – is an organized system of thunderstorms with sustained winds of 38 mph.
Tropical Storm – is an organized system of strong thunderstorms with sustained winds of 39 to 73 mph (34-63 knots).
Hurricane – is an intense tropical weather system with sustained winds of 74 mph (64 knots) or higher.
Formation Hurricanes are products of the Tropical Ocean and atmosphere. Hurricanes are powered by heat from the sea; they are steered by easterly winds and the westerly temperate as well as their own ferocious energy. Hurricanes are formed in the tropical regions. They form there because they need warm water of at least 80º Fahrenheit. They also need high humidity with moist air, light winds, and very warm surface temperatures to succeed. Around their core, winds grow with great velocity, generating violent seas. While moving ashore, they sweep the ocean inward while generating tornadoes and producing torrential rains and floods. The first sign of a hurricane is a cluster
References: Cunningham, W.P. Saigo, B.W. (1997) Environmental Science McGraw- Hill companies Eglinton, C. (2009) about .com guides. Retrieved October 29, 2010 from www.chuckegg.com Oblack, R. (2010) weather. About.com guides. Retrieved November 01, 2010 from www.about.com