The Coriolis effect helps determine the direction of planetary, or global, winds by causing them to curve, or deflect, as the Earth rotates. In the Northern Hemisphere, winds curve to the right in the direction of motion. Air moving toward the equator curves to the west, while air moving away from the equator curves to the east. This pattern is reversed in the Southern Hemisphere, where winds curve to the left in the direction of motion: winds moving toward the equator curve to the west, and winds moving away from the equator curve to the east. The difference in temperature between land and sea also influences global winds.
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