青藏高原热力状况对东亚夏季副热带西风急流的影响

利用1961--2004年NCEP／NCAR月平均温度5层和200hPa风场再分析格点资料，以及通过倒算法得到的热源资料，采用SVD方法研究了夏季东亚地区副热带西风急流与青藏高原平均温度场的耦合特征，考察了青藏高原热源及其与西太平洋热源差对夏季东亚副热带西风急流的影响。结果表明，夏季整个青藏高原特别是高原北部平均温度场与急流中心强度变化联系紧密，而高原东南部平均温度场主要体现了夏季西风急流位置纬向一致的南北移动；其次，夏季副热带西风急流的变化还与青藏高原西南部与菲律宾以东的西太平洋热源差变化有密切联系。

THERMAL EFFECT OF TIBETAN PLATEAU ON EAST ASIA SUBTROPICAL WESTERLY JET IN SUMMER

With the use of the 1961--2004 NCEP/NCAR reanalyzed monthly data of temperature and 200 hPa wind field as well as the data of heat resource by inverse method, the coupling feature of the summer East Asia subtropical westerly jet and the mean temperature field over the Tibetan Plateau was studied with the SVD method to investigate the influence of the heat source difference between the Tibetan Plateau and the Western Pacific on East Asian subtropical westerly jet in summer. The results indicated that the intensity of East Asian subtropical westerly jet was related closely to the mean temperature field over the whole Tibetan Plateau, especially the north of Tibetan Plateau, and the latitudinal displacement of westerly jet was related to the mean temperature field over the southeast of Tibetan Plateau. Moreover, the variation of East Asia subtropical westerly jet was also related to the change of the heat source difference between the Tibetan Plateau and the Western Pacific east to Philippine.