Mechanism for the Correlation of Winter Fresh Snow Extent over Northern Eurasia and Summer Climate Anomalies in China: The Important Role of Eurasian Winter Fresh Snow Extent

Based on previous studies (Mu and Zhou, 2012), the linkage mechanism between winter northern Eurasian total fresh snow extent (T_FSE) and subsequent summer climate anomalies in China is investigated in depth using empirical orthogonal function (EOF) and correlation analysis, with the primary purpose of finding the key region of fresh snow extent over northern Eurasia. The results show that the correlation between mid-latitude fresh snow extent in Europe (T_FSE-1) and subsequent summer climate anomalies in China is unremarkable. However, T_FSE-1 variability supports the physical mechanism for T_FSE summer climate correlation. Thus, T_FSE-1 provides a crucial influence on the climatic effects of T_FSE. The role of mid-latitude fresh snow extent in Asia (T_FSE-2) is unknown. However, winter fresh snow extent in Eurasian middle-latitude regions (T_FSE-1-2), which significantly affects the summer climate in China, dominates climatic effects of T_FSE because the correlation between T_FSE-1-2 and the summer climate in China has a clearer physical mechanism than the correlation between T_FSE and the summer climate, which suggests that T_FSE-1-2 could replace T_FSE in climate forecasts.