The Study of Correlations between Air-Sea Temperature Difference and Precipitation and between Wind and Precipitation in the Yeongdong Coastal Region in Relation to the Siberian High

In this study, the correlations between AST850 and precipitation, and those between WDT and precipitation in the Yeongdong coastal region under the direct/indirect influence of the expansion of cP (continental polar air mass) high were quantitatively analyzed based on the winter season data for the last 20 years, according to surface pressure patterns such as Type 1 (cP high expansion type), Type 2 (cP high expansion + trough type), Type 4 (South trough type), and Type 5 (East Sea trough type). Here, AST850 represents ‘sea surface temperature minus temperature on 850 hPa level’ and WDT represents ‘a speed of 1000 hPa wind projected onto a certain wind direction times precipitation duration in hour’. First, the correlation coefficients between AST850 and precipitation in Type 1, Type 2, and Type 5 cases were 0.253, 0.384, and 0.398 respectively, indicating that a tendency of increasing precipitation linearly with the value of AST850 is slightly presented. In the case of Type 4, however, the coefficient was −0.15, representing almost no linear correlation between AST850 and precipitation. In the correlation between WDT and precipitation, there was the largest correlation coefficient (0.464) between WDT along a direction of 90 and at EN1 in Type 1 cases. In the case of Type 2, there was the largest correlation coefficient (0.767) between WDT along a direction of 67.5 and at ES1. In the case of Type 4, there was the largest correlation coefficient (0.559) between WDT along a direction of 22.5 and at EN2. Finally, in the case of Type 5, there was the largest correlation coefficient (0.945) between WDT along a direction of 315 and at SE1, representing the largest coefficient among the types. It was found that surface wind directions with the highest correlations to precipitation in the Yeongdong coastal area on winter season were varied according to surface pressure patterns, and that the correlations between WDT and precipitation were higher than those between AST850 and precipitation.