Asymmetry of the Intertropical Convergence Zone it is the equatorial upwelling that prevents the ITCZ being created at the equator. To explain this simply, upwelling brings cold water to the surface, which will cool the above atmosphere and make it stable because of relative high air density due to low temperature. Thus, this area of the equator is different compared to the strong vertical convection and abundant precipitation of the ITCZ. As a result, the SST is latitudinally asymmetric. 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.
Winds in the Age of Sail He took the southeast trade winds directly northwest across the South Atlantic to the Cape Verde Islands, the Azores, and home. Not only did Da Gama find a sea route to India, he discovered the most efficient sailing route there and back. In 1500 Pedro Álvares Cabral sailed somewhat west of Da Gama's route and bumped onto the coast of Brazil. Portuguese and Dutch in the Indian Ocean: After a few more voyages the Portuguese learned two things: that there was little market for European goods in the east, and the large Portuguese ships could outfight nearly any local craft.