Asymmetry of the Intertropical Convergence Zone Asymmetry of the Intertropical Convergence Zone There are a number of explanations of the asymmetry of the Intertropical Convergence Zone (ITCZ), known by sailors as The Doldrums. The ITCZ would be expected to overlie the geographic equator according to symmetric solar radiation. However, the ITCZ is mostly perennial in the northern hemisphere and in the eastern Pacific and Atlantic Oceans. It was originally explained by the asymmetrical distribution of continents. However, the distribution of land and ocean is severely asymmetric in the Indian Ocean, yet the ITCZ moves back and forth there between the southern and northern hemispheres. Continents surround
Thermal equator of maximum temperatures surrounding the globe which migrates roughly between the Tropic of Cancer and the Tropic of Capricorn. This region is known as the Intertropical Convergence Zone where the Earth orbits the Sun. This zone is the result of trade winds from the northern and southern part of the hemisphere eventually joining together. Still another definition states that the thermal equator is the latitude at which insolation is identical throughout the year. This is not the same as the astronomical equator because the Earth reaches perihelion (the minimum distance from the Sun in its orbit) in early January and