Winter snow cover influences growing-season vegetation productivity non-uniformly in the Northern Hemisphere

Abstract

Ongoing changes in snow cover significantly affect vegetation productivity, but the actual effect of snow cover remains unclear due to a poor understanding of its lagged effect. Here, we used multisource datasets to investigate the lagged effect of snow cover on vegetation productivity in Northern Hemisphere ( > 40°N) ecosystems from 2000 to 2018. We found a widespread lagged effect of snow cover ( > 40%, P < 0.05) on growing season vegetation productivity (mean ~73-day lag). The effect of snow cover on vegetation productivity was underestimated by over 10% of the areas without considering regional lagged time differences. A longer lagged effect generally occurred in warm and humid areas, and areas with increased lagged time (66%) were greater than those with decreased trends. Moreover, changes in lagged effect were strongly driven by climate factors, followed by soil and topography factors. These findings emphasize the need to consider lagged time differences of snow cover when investigating snow-vegetation productivity interactions.