[In this section will appear abstracts which are too long to be included as annotations to the list of glaciological works which follows.]

Simpson, C. G. Possible Causes of Change in Climate and their Limitations. Proc. Linnean Society, London, 1940, pp. 190–219.

• (a) The mean temperature and mean rainfall of zones are unaffected by the distribution of land and water, but large differences in local climate may be effected by redistribution of land and water, chiefly in the extremes of temperature and rainfall. The changes of climate during the Pleistocene period could not have been caused by changes in land and water.

• (b) The effect of changes in the elements of the earth’s orbit is so small that the mean annual temperatures cannot be affected by more than a fraction of a degree Centigrade, while the temperatures of the warmest and coldest months can only be affected by as much as 2° C. in extreme cases in high latitude.

  “Generally speaking, the temperature of the wärmest month is above 5° C. in non-glacierized regions and below 5° C. in glacierized regions; the temperature of the coldest month is of little importance.”

• (c) An increase in solar radiation produces an increase in temperature, in the amount of cloud and in precipitation, and a decrease produces the reverse. The large changes in climate during the Pleistocene period are probablv due to changes in solar radiation: but it is not yet clear whether the glacial epochs were caused by an increase or decrease of solar radiation.