Wind speed and snow evaporation in a stand of juvenile lodgepole pine in Alberta

Abstract

Wind speed and snow evaporation were measured in a small artificial stand of 2.5-m lodgepole pines and in an adjacent field during the winter of 1987. Stand densities of 2500, 1650, and 800 stems/ha were obtained through periodic removal of trees. The reduction of wind speed brought about by the trees is a linear function of [Formula: see text], the angle of view from the anemometer to the tops of the surrounding trees. When the stand was at full density, snow evaporation was about one-third of that measured in the open field, and when stand density was reduced to 1650 stems/ha, snow evaporation was equal to that of the open field. Because of high melt rates, no data were obtained from the lowest stand density. The results are summarized in a predictive relation between the angle of view [Formula: see text] and the reduction in snow evaporation caused by the trees.