Intertropical Convergence Zone (ITCZ)

The Intertropical Convergence Zone is the equatorial belt of low pressure where the northeast and southeast trade winds converge, forcing warm moist air to rise in deep convection. It is the ascending branch of the Hadley cells and the rainiest zone on Earth, marked by a near-continuous band of cumulonimbus, heavy showers, and thunderstorms with light surface winds, the doldrums. The ITCZ migrates seasonally with the thermal equator, reaching far north over Asia and Africa in boreal summer and dipping south in austral summer, driving the monsoons. Its position and strength govern tropical rainfall and the onset of tropical cyclogenesis.