Diminishing snowpack intensifies crop yields sensitivity to soil moisture in the northern hemisphere

Abstract. Crops face increasing threats from drought due to global warming, causing declines in yield. Snowpack, as a distinct seasonal water resource, contributes to soil moisture that can supply additional water during the growing season, thereby reducing exposure to soil moisture deficit and stabilizing yield. However, the response of crop yield to snowpack, and the degree to which snowpack influence crop yield sensitivity to soil moisture, remain insufficiently understood. In this study, we combined snowpack, climate, soil, and crop yield datasets in the Northern Hemisphere from 2000 to 2022 to assess how snowpack affects the relation between soil moisture and yield of maize, spring wheat, and soybean. Our analysis reveals that crop yields respond positively to variations in snowpack, with the area showing significant positive correlation accounting for 52.99 % for maize, 72.75 % for spring wheat, and 82.66 % for soybean. Snowpack plays a predominantly negative regulatory role, with greater snowpack exerting a stronger buffering effect against drought impacts. In particular, late-spring snowmelt is the most influential contributor to this buffering effect. Moreover, an earlier shift of snowmelt peaks from April to March intensifies the temporal mismatch between water availability and water demand of crops, aggravating yield reductions. Among different crops, maize and soybean exhibit the strongest sensitivity to snowpack changes. These findings highlight the crucial role of snowpack in regulating soil moisture-yield relation, informing strategies to safeguard food production under climate change.