中文摘要：

利用1950--2009年Hadley环流中心全球月平均海表温度资料、1960-2009年NCEP／NCAR再分析资料以及中国气象局整编的160站降水资料，研究分析了印度洋偶极子（IOD）和太平洋异常海温（ENSO）对中国冬季降水的协同影响和不同作用，通过对比分析，揭示了IOD独立发生、ENSO独立发生以及IOD与ENSO联合发生时中国冬季降水的差异。研究结果表明：IOD异常海温和ENSO异常海温的出现虽然具有较高的协同性，但二者对我国冬季降水的影响效应不尽相同，IOD与ENSO的同时发生并不是两者单独发生时各自作用的叠加，而是具有协同或抵消作用。仅有IOD发生时，其正位相年使得中国西南（云南西部除外）、华南以及华北、东北地区的冬季降水出现正异常，在江淮流域出现负异常，反之亦然。但是IOD正位相比负位相对中国冬季降水的影响更显著。当IOD与ENSO同时出现时，IOD的作用使得ENSO对我国西南（云南西部除外）、内蒙、东北地区冬季降水的影响作用更为显著。此外还初步分析了IOD与中国冬季降水关系影响的环流成因。

英文摘要：

Based on the 1950--2009 data of Hadley Center monthly global SST, 1960--2009 NCEP/NCAR reanalysis and rainfall over 160 stations in China, investigation is undertaken for the synergistic effect and different roles of Indian Ocean Dipole （IOD） and Pacific SSTA （ENSO） on winter rainfall in China. And the difference of winter precipitation is revealed by comparative analysis between years of Irtdian Ocean Dipole （IOD） only, ENSO only and IOD and ENSO concurrence. It is shown that although the sea surface temperature anomalies of IOD and ENSO often occur simultaneously, their effects on winter precipitation vary; they do not just superimpose their roles when occurring respectively but have synergistic or offsetting effect. The winter rainfall will be more than normal in Southwest China （except western Yunnan）, Inner Mongolia region and Northeast China in the positive phase IOD year, and it will be less in Yangtze River and Huaihe River basins, and vice versa. However, the impact of the IOD positive phase on winter precipitation is more significant than that of the negative phase. When the IOD appears along with ENSO, the ENSO signal, due to the influence of IOD, affects the winter precipitation of Southwest China （except western Yunnan）, Inner Mongolia region and Northeast China more significantly. In addition, the circulation Causation is also examined preliminarily for the influence of IOD on the winter rainfall in China.