Spatial and Temporal Variations of Freezing and Thawing Indices From 1960 to 2020 in Mongolia

Mongolia is one of the most sensitive regions to climate change, located in transition several natural and permafrost zones. Long-term trends air freezing thawing indices can therefore enhance our understanding change. This study focuses on changes spatiotemporal patterns over from 1960 2020, using observations at 30 meteorological stations. Our results shows that index ranges ?945.5 ?4,793.6°C day, while 1,164.4 4,021.3°C day Mongolia, their spatial clearly link latitude altitude. During period, trend (14.4°C-day per year) was larger than (up ?10.1°C-day year), which net increase temperature by 2.4°C across Mongolia. Overall, low latitudes altitudes (e.g., Gobi-desert, steppes, Great lake depression major river valleys) high (mountain regions), it opposite for index. The highest values both (i.e. least negative values) have occurred during last 2 decades. As mean annual confirm intensive warming, increased degradation shallower seasonally frozen ground are expected throughout