关于ENSO事件及其对中国气候影响研究的综述

A REVIEW OF STUDYS ON THE INFLUENCE OF ENSO EVENTS ON THE CLIMATE IN CHINA

Nio指数和SOI是表征ENSO事件的两个主要特征值。根据Nio3.4区指数变化,1950年以来共发生15次ElNio事件和11次LaNia事件。ElNio年,热带中、东太平洋上的岛屿及沿岸国家多暴雨洪涝,印度、印度尼西亚、澳大利亚等国家发生持续干旱,中国东北地区夏、秋季降水及年降水都偏少,江南地区降水偏多;太平洋和大西洋地区发生的热带风暴以及登陆中国的台风数都比常年偏少;加拿大西南部和美国北部暖冬,东亚夏季低温,中国常出现暖冬凉夏。LaNia年则基本上相反,赤道太平洋中、东部地区干旱少雨,西太平洋上的台风和大西洋飓风及登陆中国的台风明显增多,中国汛期主要雨带偏北,易出现热夏寒冬。

Nio Index (Sea-Surface Temperature Indices) and SOI(the Southern Oscillation Index)are two main indices used in monitoring and definingand predicting ENSO events. Based on Nio3.4 Index since 1950, 15 El Nio events and 11 La Nia events have been identified. An El Nio events results in heavy rainfall, even floods in the equatorialcentral and eastern Pacific, South America and south China, but scarce rainfall even severe droughts in India, Indonesia, Malaysia, eastern Australia. At the same time, rainfallis reduced over northern area of east China in summer,autumn and all year, tropical cyclone frequencies in the Pacific and Atlantic and landing China typhoon frequencies are decreased. It is warm over southeast Canada and northern U.S.A in winter, low temperature over eastern Asia, warm in winter and cool in summer over China. But during La Nia events, this results in droughts in central and eastern tropical Pacific, tropical cyclone or typhoon frequencies in the Pacific and Atlantic and landingChina typhoon frequencies are increased . The rain band in China during the high-water season is to the north . It is hotter in summerand colder in winter over China.