东亚夏季风的变化及对松嫩流域旱涝影响

根据近50年来美国NCEP/NCAR再分析资料及松嫩流域39个站1951~2000年的逐日降水资料,用相关分析、合成、对比分析及小波分析等方法分析了东亚夏季风的年际、年代际变化及对松嫩流域旱涝的影响。结果表明,东亚夏季风对位于中高纬度的松嫩流域的旱涝趋势确有影响,但东亚夏季风的年际、年代际变化很大。东亚夏季风与松嫩流域盛夏降水特点相似:都具有3~5年、10~12年的变化周期,在20世纪60年代末、80年代初都有气候突变。松嫩流域的旱涝趋势除与东亚夏季风有关外,还与中高纬度的西风带天气系统及西太平洋副热带高压密切相关。

Variability of East Asian Summer Monsoon and Its Association with Rainfall Trend over Songhuajiang-Nenjiang River Basin

The interannual and interdecadal variability of East Asian summer monsoon and its impacts on summer precipitation over the Songhuajiang-Nenjiang River basin are investigated based on NCAR/NCEP reanalysis data and 39-station rainfall data from 1951 to 2000.The results show that both East Asian summer monsoon and the rainfall over the Songhuajiang-Nenjiang River Basin possesses the variation periods of 3-5 and 10-12 years.Two climatic jumps occurred at the end of the 1960s and the beginning of the 1980s,respectively.East Asian summer monsoon significantly influences the rainfall over the Songhuajiang-Nenjiang River basin.In addition,factors such as the westerly and the Western Pacific subtropical high have also impacts on summer rainfall over the Songhuajiang-Nenjiang River basin.