Abstract
To statistically examine the large-scale atmospheric circulation that relates to anomalous snow over Mongolia, monthly-based snow depth and temperature data at Mongolian 23 stations were analyzed. A principal component analysis (PCA) was applied to interannual anomalies of January snow depth during 1961-1990. The first mode (PC1) shows a pattern having widespread loadings of the same sign over the entire Mongolian region, while the second mode (PC2) exhibits a northeast-southwest dipole pattern. Lag correlation analyses of interannual anomalies revealed that the PC1 time coefficient for January is highly correlated (r=0.43) with the large-scale circulation mode of the North Atlantic Oscillation (NAO) for November. The PC2 highly correlated (r=−0.47) with the mode of the Eurasian Pattern 1 (EU1) for December. The circulation modes are derived from the R-PCA of 500 hPa heights.
