1961~2022年松花江流域降雪变化特征研究

Study on the Variation Characteristics of Snowfall over the Songhua River Basin from 1961 to 2022

摘要: 基于ERA5再分析逐日降雪量资料，本文分析了1961~2022年松花江流域降雪量和降雪日数的时空演变特征及其对气候变暖的响应。结果表明，流域多年平均年降雪量为32.56 mm，呈极显著增加趋势，并在2008年发生由少到多的突变，突变后降雪量较突变前增加40%；降雪量对1987年气温突变响应敏感。多年平均年降雪日数为24.49 d，变化趋势不显著，且未检测到明显突变，对气温升高响应不敏感。空间分布上，降雪量和降雪日数均呈东北部和南部多、西部和中部少的格局，高值区位于小兴安岭东侧及长白山南段西侧，低值区位于松嫩平原腹地及大兴安岭南部。空间趋势显示，降雪量在流域东部、北部及西部显著增加，而降雪日数在相同区域显著减少，中部地区变化均不显著。时空耦合特征表明，松花江流域降雪量的增加主要源于单次降雪强度的增强，而非降雪频率的增多。研究结果可为区域水资源管理及气候变化适应提供科学依据。

Abstract: Based on the ERA5 reanalysis daily snowfall data, this study analyzes the spatiotemporal evolution characteristics of snowfall amount and snowfall days over the Songhua River Basin from 1961 to 2022, as well as their responses to climate warming. The results show that the multi-year mean annual snowfall amount in the basin is 32.56 mm, exhibiting an extremely significant increasing trend (2.47 mm/10a, P < 0.01), with an abrupt change from low to high occurring in 2008. After the abrupt change, the snowfall amount increased by 40% compared to that before the change. The snowfall amount shows a sensitive response to the temperature abrupt change in 1987, with a lag of approximately 21 years. The multi-year mean annual snowfall days are 24.49 d, with no significant trend (−0.23 d/10a, P > 0.05) and no detectable abrupt change, indicating an insensitive response to temperature increase. Spatially, both snowfall amount and snowfall days exhibit a pattern of “more in the northeast and south, less in the west and central” regions. High-value areas are located on the eastern side of the Lesser Khingan Mountains and the western side of the southern section of the Changbai Mountains, while low-value areas are distributed in the hinterland of the Songnen Plain and the southern Greater Khingan Mountains. Spatial trend analysis reveals that snowfall amount has increased significantly in the eastern, northern, and western parts of the basin, whereas snowfall days have decreased significantly in the same regions, with no significant changes in the central plain area. This spatiotemporal coupling characteristic of increasing amount but decreasing days indicates that the increase in snowfall amount over the Songhua River Basin is primarily attributed to the enhancement of single snowfall event intensity, rather than an increase in snowfall frequency. The findings can provide scientific basis for regional water resource management and climate change adaptation.