贵州夏季降水异常的环流特征分析

利用美国NCEP/NCAR月平均高度及风场再分析资料和中国月平均降水资料,分析了贵州多、少雨年夏季环流的平均距平场特征.结果表明:贵州多、少雨年夏季环流具有明显的不同特征.多雨年南亚高压偏弱,西太平洋副热带高压较常年偏强,脊线明显偏南偏西,且影响贵州的印度西南季风、西太平洋副热带季风较常年也偏强,影响贵州的中、东路冷空气强.少雨年西太平洋副热带高压明显偏强,脊线较常年明显偏北,其它环流特征与多雨年相反.

Analysis on Circulation Characteristic of Precipitation Anomalies in Guizhou Summer

Using the NCEP/NCAR monthly mean meteorological reanalysis data and the monthly precipitation data in China,the anomalous characteristic of summer circulation in more and less rainfall years in Guizhou are studied in this paper.It is found that there are obvious differences of summer circulation between more and less rainfall years.In more rainfall years of Guizhou,South Asian High is weak,West Pacific Subtropic High is stronger than normal year and the ridge axis of it is far southward and westward;Indian summer monsoon and subtropical summer monsoon that affect Guizhou precipitation is more stronger than normal years;the cold air of middle and east routes are strong.In less rainfall years of Guizhou,West Pacific Subtropical High is more stronger than normal years and the ridge axis of it is far northward.In addition,the anomalies of circulation in more rainfall years of Guizhou are usually in opposite.