Based on data from the 1979 TIPMEX with the aid of an empiricalformula. detailed study is done on the role of the plateau as a surface heatsource and the distribution of the various components of heat balanceover the plateau and its adjacent areas. Emphasis is placed on theeffect of the march of seasons on surface heating including both sensibleand latent. The principal way through which the surface heats theatmosphere and the variation of intensity of heating are revealed. Itis shown that sensible heat predominates in the dry season withmaximum intensity appearing in the west and latent heat plays amore important role during the wet months, especially in the east. Inaddition, a discussion of the magnitude and distribution of drag coeffi-cient C_D is presented and the mean value is found to range from 4·10^-3to 5·10^-3. The values are higher in the east than in the west andgreater in the valleys than on the plains.