EFFECTS OF CHANGING THE SOLAR CONSTANT ON THE CLIMATE OF A GENERAL CIRCULATION MODEL.

A study is conducted to evaluate the response of a simplified three-dimensional model climate to changes of the solar constant. The model explicitly computes the heat transport by large-scale atmospheric disturbances. It contains the following simplifications: a limited computational domain, an idealized topography, no heat transport by ocean currents, no seasonal variation, and fixed cloudiness. It is found that the temperature of the model troposphere increases with increasing solar radiation. One of the most interesting features of this investigation is the extreme sensitivity of the intensity of the computed hydrologic cycle to small changes of the solar constant. Finally, it is shown that the latitude of maximum snowfall retreats poleward as the solar constant is increased. Furthermore, the total amounts of snowfall and snow accumulation decrease markedly with increasing insolation.