ALBEDO MODEL FOR A TROPICAL DRY DECIDUOUS FOREST IN WESTERN MEXICO

A simple albedo model is presented for a tropical dry deciduous forest. The model is based on point observations of the solar radiation, leaf cover of the vegetation. precipitation and air temperature from 1981 to 1988 in western Mexico. Four main periods were noted: leafing, leafed, leaf-fall and leafless. During the leafed period the albedo was almost constant (0.16) but increased slowly in the leaf-fall period, at a rate of 0.0008/day, until its maximal values in the leafless period (0.24). During the leafing and leafed periods, the albedo decrease was a hyperbolic function of precipitation at a rate of 7.9 albedo percentage/mm. Albedo showed a linear regression on leaf cover and decreased at a rate of 0.119 albedo percentage per leaf cover percentage.