trade winds

trade winds movement of air toward the equator, from the NE in the Northern Hemisphere and from the SE in the Southern Hemisphere. The trade winds originate on the equatorial sides of the horse latitudes , which are two belts of high air pressure, one lying between 25° and 30° north of the equator and the other lying between 25° and 30° south of it. The high air pressure in these belts forces air to move toward a belt of low air pressure along the equator called the doldrums . The air converging at the doldrums rises high over the earth, recirculates poleward, and sinks back toward the earth's surface in the region of the horse latitudes, thus completing a cycle. The air does not move directly north or south because it is deflected by the rotation of the earth. See wind ; Coriolis effect .

trade winds Steady wind that blows westwards towards the Equator from subtropical high pressure zones between latitudes 30° and 40° n and s.

trade winds are prevailing winds that blow steadily from the high-pressure zones. These occur in the horse latitudes that lie close to the Tropics of Cancer and Capricorn, between 25° and 30° both to the north and to the south of the equator, towards the doldrums now known as the Intertropical Convergence Zone or ITCZ. Intense solar heating at the equator causes the air to rise and this draws in the winds from the high-pressure regions. These winds are deflected by Coriolis forces so, instead of blowing directly from north or south, they blow from the north-east in the northern hemisphere and from the south-west in the southern hemisphere. During the age of sail, ships voyaging across the North Atlantic from east to west exploited the trade winds, with the return voyage following a more northerly route where the prevailing winds are south-westerly.

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M. V. Angel