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Wind - The Coriolis Effect And Wind Direction, Friction And Wind Movement, Local Winds

pressure earth surface gradient

The term wind refers to any flow of air relative to the Earth's surface in a roughly horizontal direction. Breezes that blow back and forth from a body of water to adjacent land areas—on-shore and off-shore breezes—are examples of wind.

The ultimate cause of Earth's winds is solar energy. When sunlight strikes Earth's surface, it heats that surface differently. Newly turned soil, for example, absorbs more heat than does snow.

Uneven heating of Earth's surface, in turn, causes differences in air pressure at various locations. On a weather map, these pressure differences can be found by locating isobars, lines that connect points of equal pressure. The pressure at two points on two different isobars will be different. A pressure gradient is said to exist between these two points. It is this pressure gradient that provides the force that drives air from one point to the other, causing wind to blow from one point to the other. The magnitude of the winds blowing between any two points is determined by the pressure gradient between those two points.

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almost 7 years ago

I liked it very much. You can go into detail of how the Coriolis effect and th pressure gradient influences wind speed and direction.

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almost 7 years ago

I liked it very much. You can go into detail of how the Coriolis effect and th pressure gradient influences wind speed and direction.

Vote down Vote up

over 10 years ago

Good info - could be improved with illustrations perhaps, to make it clearer?