Interactions and relations between mountain permafrost, glaciers, snow and water

Abstract

AbstractThere are problems in determining the amount of precipitation at a given site in mountain permafrost areas, because snow can be redistributed by wind or avalanches. Both snow and rain greatly affect permafrost distribution. Surface soil conditions also affect permafrost distribution. Dry blocky surfaces, peaty soils and soils with a thick organic mat tend to favour permafrost development. Active layers are deepest on dry mineral soils at low latitudes. Moist soils have thin active layers which exhibit the zero curtain effect during freezing and thawing. Meteoric H2O enters permafrost in response to thermal gradients. The H2O content may reach 80% by volume in its upper layers in some rock glaciers. In Kazakhstan a perched water table occurs above the thawing front in the active layer and provides a reliable supply of water to plants, so that the permafrost lands have a lush meadow tundra in summer. The physical and chemical properties of the discharge from mountain permafrost areas can be used to differentiate it from glacial discharge and groundwater. There is an antipathetic relationship between the lower limit of permafrost and the equilibrium line on glaciers. Gorbunov's Continentality Index is the only system for classifying the climate of mountain permafrost areas that indicates their great climatic variability.