THE GENERAL CIRCULATION OF THE TROPICAL AND EQUATORIAL ATMOSPHERE

Recent experiences with tropical meteorology around the world have brought to light the frequent existence of a zonal band of west winds in the vicinity of the equator, which appears not to be associated with the westerlies of middle latitudes, but which rather seems to be found between the trades of the two hemispheres. The boundaries of the equatorial westerlies are usually characterized by increased cloudiness and poor weather. In this paper an attempt is made to prove that the westerlies of equatorial regions are not simply transitory phenomena but instead should be considered as an integral part of the normal general circulation of the atmosphere. Seasonal variation of the latitude of maximum insolation is the factor introduced to explain the existence of the west winds. A second explanatory theory is discussed in which radiation from the cloud tops of the “intertropical convergence zone” locally reverses the equatorial solenoidal field to produce two new lines of convergence, one on each si...