ANTITRADE WIND

steady wind that blows poleward and eastward between latitudes 30 N and 30 S, at altitudes of 2 to 12 kilometres (about 1 to 7 miles). Such winds overlie the westward-blowing trade winds and descend poleward, where they merge with the mid-latitude westerly winds. The subtropical high-pressure belts at 3035 N and 3035 S result partially from the descent of the antitrades to the surface. See also atmospheric circulation.