As a crucial component of the climate system, snow cover plays an important role on surface energy budgets, hydrological cycles and socioeconomic development. This paper investigated the spatiotemporal patterns of snow depth across the Qinghai Plateau (QP) during 1980–2018 based on passive microwave (PMW) satellite observation and reanalysis products. The study identified the relationships between the changes in PMW snow depth and topographic features and revealed the impact of climatic variables (air temperature, precipitation and wind speed) and large-scale atmospheric circulations on observed snow depth variability. The results show that the spatial pattern of snow depth climatology is similar in all datasets, except in terms of magnitude, with high values in the southern and southeastern parts of the QP and low values in the eastern and northwestern parts. Average snow depth correlates positively with precipitation, elevation and slope, and negatively with air temperature and wind speed. The long-term trends in snow depth vary with the season and the datasets. The PMW snow depth across the QP shows a significant annual (−0.125 cm·decades⁻¹, p < .10) and spring (−0.184 cm·decades⁻¹, p < .05) negative trend, while snow depth for ERA5 and MERRA2 does not present significant trends. Air temperature dominates total snow depth variation over the QP, explaining 43.85, 24.88 and 47.28% of annual, winter and spring PMW snow depth variations, which significantly affects snow depth variations in most parts of the QP, yet the effects of precipitation and wind speed on snow depth variation exhibit significant regional differences, and atmospheric circulations (e.g., AMO) also have a remarkable controlling effect on some localized areas.

中文翻译：

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1980—2018年青海高原积雪深度变化及其影响因素

作为气候系统的重要组成部分，积雪在地表能量收支、水文循环和社会经济发展方面发挥着重要作用。本文基于被动微波 (PMW) 卫星观测和再分析产品，研究了 1980-2018 年青海高原 (QP) 积雪深度的时空格局。该研究确定了 PMW 雪深变化与地形特征之间的关系，并揭示了气候变量（气温、降水和风速）和大尺度大气环流对观测到的雪深变化的影响。结果表明，雪深气候学的空间格局在所有数据集中都是相似的，除了在幅度方面，QP 南部和东南部具有高值，东部和西北部具有低值。平均积雪深度与降水量、海拔和坡度呈正相关，与气温和风速呈负相关。积雪深度的长期趋势随季节和数据集而变化。QP 的 PMW 雪深显示出显着的年（−0.125 cm·decades⁻¹ , p  < .10) 和春季 (−0.184 cm·decades ⁻¹ , p  < .05) 负趋势，而 ERA5 和 MERRA2 的积雪深度没有显着趋势。气温主导了 QP 的总雪深变化，解释了 43.85%、24.88% 和 47.28% 的年度、冬季和春季 PMW 雪深变化，这显着影响了 QP 大部分地区的雪深变化，但降水和风速的影响对积雪深度变化的影响表现出显着的区域差异，大气环流（如AMO）对局部地区也有显着的控制作用。