Frozen days in the Northern Hemisphere have decreased by 0.17 days per year since 1990.
The greatest declines were observed in Belarus, Ukraine, Alaska, and the Yukon region in Canada.
Rising autumn temperatures, spring precipitation and vegetation changes primarily drive this decline.
The reduction in frozen days s is expected to accelerate for the highest and moderate emission scenarios.
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Spatial distribution of accuracy for (A) the original MeASUREs product and (B) the product corrected by the stacking model.
Spatial distribution and change rate of freeze-thaw status
Impact of ST and permafrost type
Variable importance in the environmental response model
Freeze–thaw status change under three different emission scenarios
Variation trends of the frozen durations under three SSPs.