On the Reflection of Snow Surface

[摘要] Using the theoretical results of the present author's preceding papers which appeared in the former numbers of this magazine, he has calculated the intensity of reflected light from the snow surface which is supposed to be consisted of numerous facets of ice.The chief results are as follows. Whether the normals of the facets are directed uniformly into space or the majority of them are directed vertically upwards, we have the theoretical result that the reflection is strongest in the horizontal direction of the side opposite to the incident light, not in the direction expected from the regular reflection of a plane surface.As a next problem, the author has discussed the unevenness of the surface. If we separate the total reflection into two parts, one the surface reflection, the other the multiple reflection inside the medium, it will be the projections of the uneven surface that take part in the surface reflection, the hollows having little effect on it. Therefore, the amount of surface reflection will be reduced in some proportion, say 30%, than the value expected from the above theory.These facts have been confirmed also in the photometric experiment taken by H. Oura.In conclusion, the author has suggested the possibility to classify the surface conditions of snow from the intensity distribution of the reflected light.

[学科分类] 大气科学