Spatial distribution of surface hoar crystals in sparse forests

摘要: Abstract. Surface hoar size and location relate directly to avalanche initiation trigger points, they do so in small-scale spatial distributions. Physically, surface will grow where the snow is cold relative air water vapour plentiful. Vapour aside, cools at night primarily by longwave radiation emittance. Emittance can be restricted clouds, trees, terrain features. With 96 independent point samples of size, we show extreme variation that trees create, ranging from 0 14 mm an area 402 m2. We this effects using satellite photography estimate amount impinge on sky view for each point. Though physically related escape, balance as difficult itself. Thus, expected maximum areal crystal dry greyscale value only. confirm relation it a different formation cycle. There, its overall average error was 1.5 with sizes 7 mm.