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
Tropical Atlantic Variability Tropical Atlantic Variability The Tropical Atlantic Variability (TAV) is influenced by internal interaction and external effects. TAV can be discussed in different time scales: seasonal (annual cycle) and interannual. Seasonal variability is the dominant time scale of TAV, which is due to the seasonal march of the sun. This seasonal variability is related to the movement of intertropical convergence zone (ITCZ),which is the convergent zone of trade winds from south and north near the equator. It has strong vertical convection resulting to a redundant participation band and weak winds. The mean location of the ITCZ over the Atlantic Ocean is