东北地区汛期降水与全球大洋海温异常关系的SVD分析

ANOMALIES OF THE NORTHEAST CHINA FLOODS SEASON PRECIPITATION AND SVD ANALYSIS WITH SSTA IN WORLD OCEANS

利用中国160站月平均降水量资料和英国气象局整编的1950.1～1998.12全球逐月海温格点资料(格点分辨率2°×2°),采用相关分析和SVD方法研究了东北地区汛期(7～8月)降水异常与印度洋和大西洋海温异常的关系。结果表明:不同的海区对东北汛期降水异常有不同的影响。东北汛期降水与前一年6～7月西南印度洋海温有较好的负相关关系,东北西南部、东北部和西南印度洋KeyⅠ海区(23～13°S,57～77°E)为SVD耦合相关的显著区域。东北汛期降水与当年3～5月北大西洋KeyⅡ海区(21～27°N,61～75°W)有较好的正相关关系,对应了海温分布型是南北“翘翘板”型。两海区的海温异常共同对东北地区汛期降水异常有较好的预示作用。两海区海温异常对应的全国降水异常的空间分布在东北和华北地区是一致的。

Using monthly precipitation data from 160 Stations in China and global SST gridpoint data reorganized by British Meteorological Department from January 1950 to December 1998（with grid length at 2°×2°）, and with methods such as correlative analysis and SVD analysis, relations between anomalies of the Northeast China floods season （July-August） precipitation and SSTA in Indian Ocean and Atlantic Ocean are analyzed. The results indicate that different sea areas have different effect on the anomalies of Northeast China floods season precipitation. Anomalies of Northeast China floods season precipitation have a clear negative correlation with the SST in southwest Indian Ocean from July to August in previous years, the southwest and the northeast of Northeast China and the key Ⅰ marine region （23°- 13°S, 57-77 °E） are the most significant regions in SVD. Anomalies of the Northeast China floods season precipitation have a clear positive correlation with the SST in Key Ⅱ marine region （21- 27°N,61- 75 °W）in north Atlantic from present March to May. Corresponding SSTA pattern is of the ＂seesaw＂ type. Two key regions together can forecast the anomalies of the Northeast China floods season precipitation. The distribution of precipitation anomalies of China corresponding with SSTA in two marine regions is coherent in Northeast China and North China.