A Solar Radiation Model for Sub-Arctic Woodlands

Abstract

A mathematical model is presented which is used to calculate the flux of solar radiation to a melting snowpack in sub-arctic woodlands. Using tree height, branch radius, and distance between trees as input data, the model calculates both hemispherical and angular view factors. The latter are checked by a special photographic technique and good agreement is obtained. The view factors are used in conjunction with measurements of global and diffuse solar radiation at a base station to calculate the corresponding fluxes in nearby woodland. A test of the model at Schefferville, Quebec, showed that calculated and observed values were highly correlated, although the model consistently produced slight underestimates.