A NUMERICAL MODEL TO CALCULATE THE RADIATION REFLECTED FROM THE SURROUNDING MOUNTAINOUS AREAS
山区短波反射辐射的计算模式

In this paper, a unmerical model is presented to calculate the reflected radiation from the surrounding terrains in mountainous areas, on the basis of our developing models for calculating the terrain parameters and global radiation over rugged sites.The major input parameters of the model are altitude and albedo data at each grid,time interval, grid-space and the long-term average of thecloud amount and the sunshine percentage at the nearest adjacent weather station to the sudied area. The output one of it is in the formof the map of its distribution.The tests, made in Dabie Mountain, in the south of China, manifest that the reflected radiation from the surrounding terrains is in general much smaller than other components of radiat ion ballance.However, it becomes so important that it must not be neglected ifthe mountainous areas in question are entirely covered with snow, which is of some representation in the north of China in winter.The comparison of the results given by the present model and the single-slope one makes it clear that they are noticeably different in magnitude and distribution, the variation of the former being more intense from place to place than that of the latter, especially if snow-melting degree is not the same in the whole studied mountainous areas.