冬季太平洋三种海温异常型及其对欧亚大气环流的影响

通过对冬季太平洋海温场及滞后0—6月的欧亚500hPa高度场的联合REOF相关分析发现,与500hPa环流异常相联系的冬季海温异常分布可分为三种类型:EC型、KC型和WD型,其异常中心区域分别对应于赤道中东太平洋——加利福利亚海流区、黑潮区和北太平洋西风漂流区。各型海温异常对欧亚500hPa环流具有不同的滞后影响特征,滞后0—3月的影响区主要是低纬度地区,4个月以后可达中纬度地区,尤其是对我国东部上空环流的影响。无论是中纬度海洋还是低纬度海洋均可对滞后4个月以后的东亚中纬度环流产生明显影响。

THREE PATTERNS OF THE PACIFIC SST ANOMALY IN WINTER AND ITS INFLUENCES ON THE EURASIAN GENERAL CIRCULATION

Based on the Combined REOF analysis of the Pacific SST anomaly fields in wintertime and Eurasina 500hPa height fields lagging 0 to 6 months, it was found that the winter SST anomaly distribution which is correlated with 500hPa circulation can be sorted into three patterns, that is EC pattern, KC pattern and WD pattern. The anomaly centers of these patterns are located in eastern/central equatorial Pacific-Canifornia ocean current regions, kuroshio current region and west wind current region respectively. It was influences of the SST patterns on Eurasian 500hPa circulation. The influenced region is mainly located in low-latitude when lagging is 0 to 3 months and the region can extend to the mid-latitude when lagging is more than 3 months. Therefore, either low-latitude ocean or mid-latitude ocean have significant effects on mid-latitude eastAsian circulation.