Two Physical Effects of Eurasian Snow Cover on the Late-Spring and Early-Summer Rainfall in South China of 2010

This study investigated the snow albedo and hydrological effects on the precipitation in South China in 2010, based on the singular value decomposition (SVD) analysis of the Eurasian snow depth dataset and the 160-station rainfall dataset in China. Three ensemble simulations were conducted by using community atmosphere model 3.1 (CAM3.1). The first ensemble simulation includes both the snow albedo and the snow hydrological effect. The second ensemble simulation only considers the snow albedo effect but ignores the hydrological effect. The third ensemble simulation only considers the snow hydrological effect but ignores the albedo effect. The results indicate that both these effects could have impacts on the South China rainfall. However, there are great differences in amplitudes and ranges of abnormities induced by those three simulations. The magnitude of abnormities caused by the snow hydrological effect is larger than that by the albedo effect. When those two effects work together, the result agrees well with observations and the magnitude is the largest. However, the magnitude is not equal to the sum of that caused by the snow albedo and hydrological effects respectively.