Critical Role of Spring Snowmelt on Soil Moisture Retention during Meteorological Droughts in the Mid- and High Latitudes of Eurasia

Abstract Despite the increased frequency and intensity of meteorological droughts, Eurasian vegetation has demonstrated resilience during droughts or dry spells, possibly due to soil moisture retention from seasonal snowmelt. In this study, we present the first continental-scale investigation of quantifying this critical relationship through a comprehensive analysis of drought indices, snowmelt patterns, and soil moisture retention dynamics from 1960 to 2024. The results show that drought severity varies spatially, with southwestern Eurasia experiencing extreme short-term droughts [standardized precipitation index (SPI) < −2.5] and broader regions facing prolonged drought (SPI −1.5 to −1.0). Spring snowmelt exceeds 45 mm in eastern China, central/southern Russia, and northern Europe, while other regions receive less. This directly influences summer soil moisture, with high-snowmelt areas retaining more than 50 mm, compared to deficits of less than −25 mm in low-snowmelt zones such as southwestern Eurasia. Notably, summer precipitation shows weak correlations ( r < −0.25) with soil moisture retention in drought-prone areas, highlighting snowmelt’s disproportionate importance. Furthermore, the empirical orthogonal function (EOF) analysis confirms a strong snowmelt–soil moisture coupling in northern Eurasia (48.1% variance), but concerning trends emerge: snowmelt declines in Siberia and Scandinavia correspond with drying in central Asia and southern Europe. While central Russia shows increasing snowmelt, overall trends indicate reduced snowpack persistence and earlier melt timing. These changes threaten the historical balance between water availability and ecological needs. Our findings emphasize the need for adaptive water management strategies to offset the loss of spring snowmelt buffers, which serve as a natural drought defense in the mid- and high latitudes of Eurasia. Significance Statement This study explores the interplay between spring snowmelt and soil moisture retention during meteorological droughts from 1960 to 2024, specifically in the mid- and high latitudes of Eurasia. Our findings offer new insights into the hydrological processes that govern soil moisture dynamics in these regions, particularly under drought conditions. By utilizing a combination of statistical analyses, we highlight the critical role of snowmelt in influencing soil moisture behavior under the drought intensification conditions, providing implications for both climate research and drought mitigation strategies.