Snow accumulation on boards of different sizes and shapes

Abstract

Snow accumulation on trees plays a major role for the snow cover structure in snow hydrology, and in avalanche protection of boreal and subalpine forests. In order to better understand the processes associated with this, we investigated snow accumulation on boards of different sizes, shapes, and inclination. For this purpose we exposed different boards to natural and man-made snowfalls. After each snowfall, we measured the accumulated snow mass on the boards as well as different snow characteristics and meteorological conditions. The observed snow interception efficiency increased with board width for snowfalls at mean air temperatures below −3 °C. This is explained by the decreasing rebound of the snow crystals near the edges. At temperatures above −3 °C the snow interception efficiency was independent from board width because of strong wet-snow cohesion. For wet snowfalls bridging occurred even at distances of 10 cm between boards. The inclination and the shapes of the boards had a significant influence on the amount of accumulated snow. Based on the measured accumulation and meteorological data, we derived statistical models for the accumulation of snow on boards. Copyright © 1999 John Wiley & Sons, Ltd.