Hadley cell

In the atmosphere, a vertical circulation of air caused by convection. The typical Hadley cell occurs in the tropics, where hot air over the Equator in the intertropical convergence zone rises, giving the heavy rain associated with tropical rainforests. In the upper atmosphere this now dry air then spreads north and south and, cooling, descends in the latitudes of the tropics, producing the north and south tropical desert belts. After that, the air is drawn back towards the Equator, forming the northeast and southeast trade winds.