Abstract:The different influences of moderate El Niño and 2015/2016 extreme El Niño on winter and spring precipitation over southeast China,Yangtze-Huaihe Rivers Basins and southwest China are invested,based on monthly precipitation of 160 stations in China,OISST and NCEP/NCAR circulation datasets.The results are as follows:in the winter of moderate El Niño,anomalous warmer sea surface temperature(SST) over equatorial central-eastern Pacific triggers a pair of anomalous anticyclone over northwest Pacific and around Japan.The anomalous southwesterly enhances water vapor from South China Sea-northwest Pacific(SCS-WNP) to eastern China and causes positive anomalies of precipitation over southeast China and Yangtze-Huaihe Rivers Basins.On contrast,the equatorial central-eastern Pacific SST gets much warmer in the winter of 2015/2016 extreme El Niño.Meanwhile,anomalous cooler surface and lower troposphere temperature over eastern China intensify continental cold high,which results in northerly anomalies over north of Yangtze River.It is responsible for the increase of precipitation over southeast China and the decrease of precipitation over Yangtze-Huaihe Rivers Basins.Compare to the decaying phase of moderate El Niño in the spring,the increase of precipitations over southeast China and southwest China is attributed to anomalous warmer SST over northwest Indian Ocean and southeast Indian Ocean.The numerical experiments of CAM5 model demonstrate that the anomalous warmer SST over northwest Indian Ocean leads to southwesterly anomaly and triggers anomalous anticyclonic circulations over the Bay of Bengal and northwest Pacific,which is responsible for an increase in water vapor from the Indian Ocean and SCS-WNP to southwest China and southeast China.The anomalous warmer SST over southeast Indian Ocean arouses local ascending motion,and then it strengthens anomalies of descent over SCS-WNP and ascent over southeast China,resulting in positive anomalies of southeast China rainfall.