Trade winds

Equatorial east-to-west prevailing winds

The trade winds, or easterlies, are east-to-west prevailing winds that flow in Earth's equatorial region. The trade winds blow mainly from the northeast in the Northern Hemisphere and from the southeast in the Southern Hemisphere, strengthening during the winter and when the Arctic oscillation is in its warm phase. Trade winds have been used by captains of sailing ships to cross the world's oceans for centuries.

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