ENSO与青藏高原春季感热对中国夏季降水的影响

Combined Effects of ENSO and Spring Surface Sensible Heat of the Tibetan Plateau on Summer Precipitation in China

ENSO事件发生时,可对全球范围内天气造成影响,中国是受ENSO影响的第一区域。青藏高原(以下简称高原)热源变化,导致北半球大气环流变化,改变中国夏季降水分布。故研究ENSO与高原春季感热共同配置下,两个因素对中国夏季降水的影响。结果表明,ENSO与高原感热呈不显著负相关。ENSO与高原感热共同作用下合成分析可分成四类。1) 强El Niño与强高原正感热,合成降水信号不明显。2) 强El Niño与强高原负感热,江淮–江汉地区显著偏多,长江流域、东北地区降水偏多;东南–华南沿海、湖南降水偏少。3) 强La Nina与强高原正感热,华南地区降水偏多,在沿海地区降水显著偏多;四川盆地东南、江淮部分区域降水偏少。4) 强La Nina与强高原负感热,江淮、华南、华北地区降水偏多;四川盆地、东北地区、黄淮地区降水偏少。

China summer precipitation is remarkably affected by ENSO and spring surface sensible heat. Based on the sea surface temperature (SST) in Nino3 region and spring surface sensible heat of the Tibetan Plateau (SHTP) from 1979 to 2011, correlationship between ENSO and surface sensible heat of the TP and their influences on summer rainfall in China were investigated. The main results indicate that ENSO is negatively correlated with SHTP. The composite analysis can be divided into four types. 1) Under conditions of strong El Nino and strong positive SHTP, the precipitation in China has no significant signals. 2) Background of strong El Nino and strong negative SHTP, the precipita-tion is more than usual in the district of Jianghuai-Jianghan, Yangtze Basin, Northeast China, and less in zone of Southeast coastal area, South China, and hunan province. 3) Combining strong La Nina and strong positive SHTP, abundance precipitation occurs in South China, especially in coastal area, and deficiency precipitation in the region of Jianghuai and Sichuan Basin. 4) Under condition of La Nina and negative SHTP, the precipitation is more in South China, Jianghuai and North China. While, the precipitation is less in the district of northeast China and the area of Huanghuai, Sichuan Basin.