Climate change impact of land cover changes in the Kharhiraa-Turgen mountain region

Abstract

The study region experiences marked seasonal climatic contrasts, primarily influenced by the Central Asian anticyclone during winter and the South Asian continental depression in summer. The Mongolian Altai Mountains serve as a significant orographic barrier, further shaping local climatic patterns. Although spatial variability in precipitation is relatively limited, the steady increase in temperature-exacerbated in recent decades by global climate change-has intensified climatic differentiation across the region. This warming trend contributes to growing heterogeneity in environmental conditions and landscape processes, underscoring the area’s heightened sensitivity to ongoing climatic shifts. The aim was to illustrate climate and land cover shifts in the Kharkhiraa-Turgen mountain region using Landsat satellite data at a spatial scale. Temporally, changes were assessed between 2002 and 2021 at five-year intervals. By 2021, grassland coverage dominated the landscape, occupying 46.1% of the land cover, an increase of 1.9% from 2015. Conversely, bare land decreased from 37.2% in 2000 to 30.2% in 2021, while wetlands along riverbeds expanded from 14.35% in 2000 to 17.5% in 2021. In January 2000, the average air temperature was-20.5°C, compared to-18°C in January 2021, reflecting a 2.5°C increase. July temperatures rose from 16.2°C in 2000 to 17.4°C in 2021, a 1.19°C change. Summer precipitation in 2021 (151 mm) surpassed that of 2015 (70.1 mm), 2010 (118.3 mm), 2005 (106.9 mm), and 2000 (96.5 mm), indicating a relative increase in precipitation in the area. The prevalence of bare soil in the region is closely associated with the mountainous terrain, steep slopes, and patterns of soil erosion. Harsh climatic conditions further exacerbate rock exposure and hinder soil stabilization. Rainfall predominantly runs off the surface rather than infiltrating, which, in turn, facilitates the development of wetlands and water bodies in certain areas.