徐寒列,李建平,冯娟,毛江玉. 2012. 冬季北大西洋涛动与中国西南地区降水的不对称关系[J]. 气象学报, 70(6):1276-1291, doi:10.11676/qxxb2012.107
冬季北大西洋涛动与中国西南地区降水的不对称关系
The asymmetric relationship between the winter NAO and the precipitation in Southwest China
投稿时间:2011-11-28  最后修改时间:2012-06-06
DOI:10.11676/qxxb2012.107
中文关键词:  北大西洋涛动(NAO), 西南冬季降水, 里海和中东—阿拉伯海—青藏高原及其下游(CAT)遥相关型, 不对称性
英文关键词:North Atlantic Oscillation (NAO), Southwest China winter rainfall, Caspian Sea and Middle East Arabian Sea-Tibetan Plateau (CAT) teleconnection, Asymmetry
基金项目:国家重点基础研究发展规划项目(2010CB950400)、国家自然科学重点基金项目(41030961)、国家自然科学基金项目(41205046)
作者单位
徐寒列 中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室北京100029; 中国科学院大学北京100049 
李建平 中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室北京100029 
冯娟 中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室北京100029 
毛江玉 中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室北京100029 
摘要点击次数: 3249
全文下载次数: 26352
中文摘要:
      利用1951—2010年NCEP/NCAR再分析资料和中国160个站逐月降水资料,探讨了冬季北大西洋涛动(NAO)与同期中国西南地区降水的关系。结果表明,冬季北大西洋涛动与西南地区降水存在显著的正相关关系,并且,正相关具有不对称性,即当冬季北大西洋涛动处于负位相时,东亚地区环流形势不利于中国西南地区降水的形成,对应着中国西南地区冬季降水的显著减少。而当冬季北大西洋涛动处于正位相时,北大西洋涛动与中国西南地区降水的正相关关系并不显著。进一步的分析表明,与中国西南冬季降水变化密切相关的主要环流结构是里海和中东—阿拉伯海—青藏高原及其下游的遥相关型(CAT遥相关型)。北大西洋涛动与里海和中东—阿拉伯海—青藏高原及其下游的遥相关结构存在不对称关系,两者的关系仅在北大西洋涛动负位相时显著。冬季北大西洋涛动高、低指数年分别合成的波射线和波作用通量的结果表明,当冬季北大西洋涛动为负位相时,冬季地中海地区的扰动源会形成与里海和中东—阿拉伯海—青藏高原及其下游的遥相关路径一致的波射线,同时波作用通量的结果表明,定常波由里海和中东、阿拉伯海一直传播到青藏高原及下游地区,而冬季北大西洋涛动高指数年,地中海地区的扰动源所形成的波射线偏北,波动传播到达印度半岛地区之后不再向下游传播。冬季北大西洋涛动对里海和中东—阿拉伯海—青藏高原及其下游的遥相关波列的不对称影响决定了北大西洋涛动与西南冬季降水的不对称关系。
英文摘要:
      The simultaneous relationship between the North Atlantic Oscillations (NAO) and the precipitation over Southwest China in boreal winter is investigated using the NCEP/NCAR reanalysis data and 160 Chinese stations monthly rainfall datasets during 1951-2010. The results show that there is a significant positive correlation between the boreal winter NAO index (INAO) and the winter precipitation in Southwest China. Moreover, the positive correlation is asymmetric. During the winter of weak NAO years, the circulation pattern in East Asia is not favorable for precipitation in Southwest China. Contrastingly, during the winter of strong NAO years, the relationship between them is not significant. Further analysis shows that the main circulation pattern which influences the precipitation in Southwest China is a teleconnection pattern existed in the Caspian Sea and Middle East-Arabian Sea-Tibetan Plateau and the downstream area (CAT teleconnection). It is found that the CAT teleconnection pattern has an asymmetric relationship with the winter NAO, and the relationship is significant only in the winter when the NAO is in its negative phase. The results from the composite of the wave ray and the wave activity flux during strong and weak winter NAO years show that in weak winter NAO years the wave rays which were aroused by the wave sources in the Mediterranean could be consistent with the route of the CAT teleconnection pattern, and the wave-activity flux shows that the stationary wave could spread to the downstream along the Caspian Sea and Middle East Arabian Sea-Tibetan Plateau. On the other hand, in strong winter NAO years, the wave rays are to the north of the CAT teleconnection and the stationary wave could spread only to Indian Peninsular. These results indicate that the asymmetric relationship between the winter NAO and the winter rainfall over Southwest China is determined by the asymmetric influence of NAO on the CAT teleconnection.
HTML   查看全文   查看/发表评论  下载PDF阅读器
分享按钮