Further studies in world climate

The effects of changes in solar radiation on the climate of the earth are discussed with special reference to glacial phases in high latitudes and to pluvial periods which are common to the Earth as a whole. The relationship between the radiation and the glacial and pluvial phases is expressed in tabular form. Adopting the chronology of the glacial and pluvial phases during the Pleistocene Period, as published by K. P. Oakley, a curve of solar radiation is constructed using only the glacial phases; this proves to be a periodic curve with three complete oscillations between the begining of the Pleistocene Period and the present day. Using this radiation curve the periods of heavy and light precipitation are determined and compared with the pluvial periods. Three periods of heavy precipitation during the Pleistocene are indicated and a correlation of these with the observed pluvial periods in Africa is suggested.