Warming-independent shortened snow cover duration enhances vegetation greening across northern permafrost region

Reduced snow cover is becoming increasingly common in the Arctic-Boreal region under amplified warming, complicating efforts to isolate its specific impacts on plant productivity during the subsequent snow-free seasons. Here, we compiled a multi-source remote sensing dataset to disentangle the effects of warming-independent reduced snow cover across the northern permafrost region over the past 30 years. In years with shortened snow cover duration but normal climate conditions, gross primary productivity increased by a rate of 1.48 g C m−2 for every 10-day shortened snow cover duration and normalized difference vegetation index of 0.0024 in regions with increased soil temperature compared to the long-term mean. This productivity boost was primarily driven by shortened snow cover duration and early snowmelt, which enhanced soil heat uptake, accelerated permafrost thaw, and improved plant water and nutrient availability, thereby advancing spring greening. This study offers valuable insights into Arctic-Boreal climate feedback under a warming climate. Reduced snow cover duration and earlier snowmelt in permafrost regions can enhance soil heat uptake, accelerate permafrost thawing, and improve water and nutrient availability for plants, thereby promoting spring green-up, according to an analysis of remotely sensed data.