Temperature regime of mountain permafrost in the Russian Altai Mountains

This study presents the long-term temperature monitoring in the Russian Altai Mountains. In contrast to the Mongolian and Chinese parts, the modern temperature regime of the Russian Altai remains unclear. The complexity of a comprehensive understanding of permafrost conditions in the Russian Altai is related to the high dissection of the terrain, the paucity of the latest observational data, and the sparse population of permafrost areas. The general objective of this study is to determine the temperature regime on the surface, in the active layer, and in the zero annual amplitude (ZAA) layer, based on the known patterns of permafrost distribution in the region. Using automatic measuring equipment (loggers), we obtained information on the temperature of frozen and thawed ground within the altitudes from 1484 to 2879 m a. s. l. during the period from 2014 to 2020. An array of 15 loggers determined the temperature regime of bare and vegetated areas within watersheds, slopes, and valleys. N-factor parameters and surface temperature are similar to those in the Mongolian Altai, but the mean annual ground temperature at the depth of 1 m has a wide range of fluctuations (more than 32°C) based on research results, and we allocated it into three groups based on altitudinal zonality. Snow cover has a strong influence on the temperature regime, but the determination of the fine-scale variability requires additional study. Ground temperature regime during the observation period remained stable, but continued monitoring allows a more detailed assessment of the response to climatic changes.