Extreme Weather

Differences in air temperature cause air movement. The sun's energy is not absorbed evenly by different areas of the earth; large bodies of water tend to take longer to heat up than bare earth or smaller bodies of water. Air which has become warmer tends to rise until the surrounding air has the same temperature. Conversely, bodies of water tend to lose heat more slowly than land areas.

High pressure areas, where cooled air is descending, tend to have clear skies and calm weather. Cloud formation is inhibited because there is more evaporation than condensation. Low pressure areas, where air is rising, tend to have cloudy skies and more dynamic weather.

Due to the rotation of the earth, air tends to spiral in towards areas of low pressure from areas of higher pressure. Severe storms which originate over the warm oceans of the tropics are known as hurricanes in the Atlantic and typhoons in the Pacific. A tornado is much smaller in area but can be very destructive.

Hurricanes

Tornadoes

General

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