地理学报 ›› 2008, Vol. 63 ›› Issue (5): 482-490.doi: 10.11821/xb200805004

• 气候 • 上一篇    下一篇

中国地区水汽输送异常特征及其 与长江流域旱涝的关系

蒋兴文1, 李跃清1, 王鑫1,2   

  1. 1. 中国气象局成都高原气象研究所, 成都610071;
    2. 中国气象科学研究院, 北京100081
  • 收稿日期:2007-09-20 修回日期:2008-01-22 出版日期:2008-05-26 发布日期:2010-08-03
  • 作者简介:蒋兴文(1983-), 男, 研究方向: 气候变化和气候诊断。E-mail: xingwen_jiang@yahoo.com.cn
  • 基金资助:

    中国气象局气候变化专项项目(CCSF2007-23); 国家重点基础研究发展规划项目(2003CB415201); 中国气象 局成都高原所基本科研业务费专项项目(BROP200702)

Water Vapor Transportation over China and Its Relationship with Draught and Flood in the Yangtze River Basin

JIANG Xingwen1, LI Yueqing1, WANG Xin1,2   

  1. 1. Institute of Plateau Meteorology, China Meteorological Administration, Chengdu 610071, China;
    2. Chinese Academy of Meteorological Sciences, Beijing 100081, China
  • Received:2007-09-20 Revised:2008-01-22 Online:2008-05-26 Published:2010-08-03
  • Supported by:

    Climate Change Foundation of China Meteorological Administration (CMA), No.CCSF2007-23; National Basic Research Program of China, No. 2003CB415201; Basic Research Foundation of Chengdu Institute of Plateau, CMA, No. BROP200702

摘要:

利用中国地区1981-2002 年的常规观测资料和ECMWF 再分析资料, 研究了中国地区水汽输送的异常特征、水汽输送异常与长江流域降水的关系及其环流特征。研究表明: 中国地区水汽输送异常存在一些主要的模态, 其中第一模态最为显著, 其空间分布表现为在长江流域的水汽辐合或辐散, 其变化与长江流域的降水存在很好的关系。当西太平洋副热带高压偏南偏西偏强, 印度季风低压偏弱, 我国北方地区处于中高纬度槽后时, 大量来自孟加拉湾、南海、西太平洋的水汽在长江以南形成强大的西南风水汽, 与我国北方的冷空气在长江流域辐合, 容易导致长江流域降水偏多。当西太平洋副热带高压偏北偏东偏弱, 印度季风低压偏 强, 中高纬为平直西风气流时, 不利于引导低纬海洋水汽进入我国, 长江流域以南没有稳定的西南风水汽输送, 我国北方冷空气偏弱, 不易南下到长江流域, 导致在长江流域没有明显的水汽辐合, 降水容易偏少。

关键词: 水汽输送, 长江流域, 旱涝, 复数EOF

Abstract:

The characteristics of water vapor transportation over China and its relationship with precipitation anomalies in the Yangtze River Basin are analyzed by using the observed data in China and ECMWF reanalysis data from 1981 to 2002 in summer. The results indicate that the first mode of the integrated water vapor transportation is significant whose spatial distribution presents water vapor convergence or divergence in the Yangtze River Basin, and whose variation has a close relationship with the precipitation in the Yangtze River Basin. When the Western Pacific Subtropical High (WPSH) is strong and shifts southward and westward, the Indian Monsoon Low Pressure (IMLP) is weak, and the northern part of China stands behind of the middle and high latitude trough, a large amount of water vapor from Bay of Bengal (BOB), South China Sea (SCS) and Western Pacific forms a strong and steady southwest water vapor band and meets the strong cold water vapor from northern China in the Yangtze River Basin, thus it is likely to cause flood in the Yangtze River Basin. When WPSH is weak and shifts northward and eastward, IMLP is strong, and there is nearly straight west wind over the middle and high latitude, it is unfavorable for oceanic vapor extending to China and no steady and strong southwest water vapor transportation exists in the region south of the Yangtze River. Meanwhile the cold air from northern China is weak and can hardly be transported to the Yangtze River Basin. This brings on no obvious water vapor convergence and less precipitation in the Yangtze River Basin.

Key words: water vapor transportation, Yangtze River, drought and flood, complex EOF