杨若文,陶云,曹杰. 2009. 初夏东亚—太平洋遥相关波列年际变化的一种物理机制[J]. 气象学报, 67(3):426-432, doi:10.11676/qxxb2009.042
初夏东亚—太平洋遥相关波列年际变化的一种物理机制
A mechanism for the interannual variation of East Asia-Pacificteleconnection wave train in early summer
投稿时间:2007-08-02  修订日期:2007-10-08
DOI:10.11676/qxxb2009.042
中文关键词:  东亚—太平洋遥相关波列, 波-波相互作用, 波-流相互作用, 年际变化
英文关键词:East Asia Pacific teleconnection wave train, Wave-wave interaction, Waveflow interaction, Interannual variation
基金项目:国家自然科学研究基金(40475040和40775039)
作者单位
杨若文 云南大学大气科学系昆明650091 
陶云 云南大学大气科学系昆明650091
云南省气象科学研究所,昆明650034 
曹杰 云南大学大气科学系昆明650091 
摘要点击次数: 2856
全文下载次数: 3255
中文摘要:
      根据1978—2002年北半球500 hPa高度场、地表温度场以及中国夏季雨带类型资料,应用最小二乘法获得了能反映1978—2002年各年北半球大气环流演变大尺度特征的25组空间谱函数。采用改进的低截谱模式方法和多种统计假设检验方法获得了夏季东亚—太平洋遥相关波列年际变化的一个物理机制。结果表明,当大气环流的内部动力过程中大尺度波 波和波 流相互作用明显时,大气环流的演变表现出明显的非线性特征,导致初夏从低纬到高纬东亚—太平洋遥相关波列多为“-、+、-” 分布,相应的EAP指数多为正值,西太平洋副热带高压北跳明显,相应中国夏季多雨区主要位于淮河流域及其以北地区;反之,当大气环流的内部动力过程中大尺度波 波和波 流相互作用较弱时,大气环流的演变表现出较为明显的线性特征,初夏从低纬到高纬东亚—太平洋遥相关波列为“+、-、+” 分布,EAP指数多为负值,夏季西太平洋副热带高压北进不明显,相应中国夏季多雨区主要位于淮河、长江流域及以南地区。
英文摘要:
      Using 500 hPa height, surface air temperature and China summer rain belt type data from 1978 to 2002, 25 spatial spectrum function sets representing the variation of large scale atmospheric circulation were retrieved with the least square method. A mechanism for the interannual variation of the East Asia-Pacific teleconnection wave train in early summer was found through a low-order truncation spectral method and the statistical hypothesis test method. The results indicate that, when the large scale wave-wave and wave flow interactions are significant, there are obvious nonlinear features in the evolution of the atmospheric circulation, and the East Asia-Pacific teleconnection presents a “-,+,-” spatial distribution from low to high- latitudes in early summer. The corresponding index of the EAP is positive the western Pacific subtropical high shifts northward, and anomalous heavy rainfall occurs in the Huaihe Valley and its north in summer. On the contrary, when the large scale wave-wave and wave flow interactions are weak, there appear linear features in the evolution of the atmospheric circulation, the East Asia-Pacific teleconnection shows a “+,-,+” distribution from low-to high- latitudes. The corresponding index of EAP is negative, the western Pacific subtropical high does not move northward significantly, and anomalous heavy rain happens in the Yangtze and Huaihe River valleys and their south.
HTML   查看全文   查看/发表评论  下载PDF阅读器
分享按钮