which surface winds blow between the subtropical high and the equator
Trade winds The surface air that flows from these subtropical high-pressure belts toward the Equator is deflected toward the west in both hemispheres by the Coriolis effect.[12] These winds blow predominantly from the northeast in the Northern Hemisphere and from the southeast in the Southern Hemisphere.[13] Because winds are named for the direction from which the wind is blowing,[14] these winds are called the northeasterly trade winds in the Northern Hemisphere and the southeasterly trade winds in the Southern Hemisphere. The trade winds of both hemispheres meet at the doldrums.[7]
Tropical cyclone “Tropical” refers to the geographical origin of these systems, which form almost exclusively over tropical seas. “Cyclone” refers to their winds moving in a circle,[5] whirling round their central clear eye, with their winds blowing counterclockwise in the Northern Hemisphere and blowing clockwise in the Southern Hemisphere. The opposite direction of circulation is due to the Coriolis effect. Tropical cyclones typically form over large bodies of relatively warm water. They derive their energy through the evaporation of water from the ocean surface, which ultimately recondenses into clouds and rain when moist air rises and cools to saturation. This energy source differs from that of mid-latitude cyclonic storms, such as nor'easters and European windstorms, which are fueled primarily by horizontal temperature contrasts. Tropical cyclones are typically between 100 and 2,000 km (62 and 1,243 mi) in diameter.