Global Distribution of Cryosols with Mountain Permafrost: An Overview

About 30 per cent of the mountain soils with permafrost have an active layer depth (ALD) of less than 1 or 2 m and, therefore, can be classified as Cryosols. Mountain Cryosols have a total area of approximately 1.26 million km2 and account for approximately 12 per cent of the Cryosols worldwide. An ALD of less than 2 m appears to occur only where the mean annual air temperature is < -6 °C. There is a negative correlation (R = 0.86; p <0.001) between latitude (°N) and elevation (m) at which the ALD occurs at less than 2 m. Mountain Cryosols are most abundant in the western Cordillera of the USA and Canada (360 000 km2), the Qinghai-Tibet Plateau of China (280 000 km2), Greenland (185 000 km2), the Yablonoi-Sayan-Stanovoi Mountains of Russia (153 000 km2) and the Ural Mountains of Russia (90 000 km2). Despite that the Qinghai-Tibet Plateau contains 70 per cent of the world's mountain permafrost, only about 20 per cent of the soils are Cryosols, because they are limited to areas above 5100 m asl. Cryosols occur in the central Andes above 4900 m asl and in the southern Andes above 1000 m asl. Potential impacts of recent climate warming on mountain permafrost and Cryosols are discussed.