RADIATION THEORY OF LOCAL TEMPERATURE DIFFERENCES

Abstract

It is shown that the lowest temperature to which a radiating surface may fall depends upon the thickness of the ground surface layer which undergoes temperature change, the conductivity of the layer, and the presence of obstructions above the plane of the horizon. Integration of the heat conduction equation results in a solution which differs markedly from that given by Brunt (1932, 1941) for constant radiation. Groen's (1947) solution is shown to represent the special case of a layer of great thickness. Computations for a valley containing a frozen river, light and compact snow, and bare granite indicate that local temperature differences of 1OC or more may occur when radiation is of primary importance.