Seasonal frost depth of grounds with the bare surface, snow cover and vegetation

Abstract

Dependence of seasonal frost depth of ground on meteorological conditions and ground surface parameters was investigated with one-dimensional models. We used meteorological data of northeastern districts of China where seasonally frozen ground developed. For the case of bare surface, it is shown that the air temperature controls the frost depth and the increase of wind speed gives a slight decrease in the frost depth. The frost depth depends slightly on the soil water content except when the water content is less than 0.1, and it also depends slightly on the dry soil density. For the case of snow cover, the frost depth is seriously influenced by the thermal property of snow as well as the snow depth. For the vegetated surface, the frost depth is almost independent of forest density. A universal method to estimate the frost depth in the snow-covered ground is derived from a semi-theoretical solution of temperature profile in the snow cover. However, this method needs further elaboration.