夏季东亚高空西风急流气候特征分析

摘要

利用NCEP／NCAR全球再分析风场资料定义了西风急流强度指数和位置指数，然后利用EOF方法分析了高空西风急流的空间分布特征，从强度和位置两方面分析了西风急流与东亚环流及其与海温的关系。表明：EOF第一模态反映了东亚高空急流的位置指数，第二模态反映了高空急流的强度指数。东亚高空急流与对流层大气环流包括南亚高压，西太平洋副热带高压，东亚夏季风存在着密切关系，其气候变化与热带副热带东太平洋、印度洋海温密切相关。%By Use of the NCEP / NCAR re-analysis data of the global wind field, the westerly jet intensity index and location index was definited, and then the spatial distribution of the highaltitude westerly jet characteristics was analyzed by the method of EOF. From the two aspects of intensity and location, the relationship between East Asian westerly jet and atmospheric circulation in east Asian and the relationship between East Asian westerly jet and sea surface temperature. Analysis showed the first EOF mode in East Asia reflected the location of high-altitude jet index, the second mode reflected the strength of high-altitude jet index. East Asian high-altitude jet was closely related to the tropospheric circulation including the South Asian high-pressure, the West Pacific subtropical high-pressure, the East Asian summer monsoon. There was a close relation between the climate change and the sea surface temperature of tropical and sub-tropical eastern Pacific Ocean, Indian Ocean.