地理学报 ›› 2002, Vol. 57 ›› Issue (2): 185-193.doi: 10.11821/xb200202008

• 环境演变 • 上一篇    下一篇

西太平洋副热带高压的年代际变化 及其气候影响

龚道溢1,2, 何学兆1   

  1. 1. 北京师范大学 资源科学研究所 环境演变与自然灾害教育部重点实验室, 北京100875;
    2. 汉城国立大学 地球与环境科学学院, 汉城151-742
  • 收稿日期:2001-07-10 修回日期:2001-10-10 出版日期:2002-03-25 发布日期:2002-03-25
  • 作者简介:龚道溢 (1969- ), 男, 湖南石门人, 博士, 副教授。E-mail: gdy@pku.edu.cn
  • 基金资助:

    国家重点基础研究发展规划项目(G1998040900)和国家自然科学基金项目(40105007)

Interdecadal Change in Western Pacific Subtropical High and Climatic Effects

GONG Dao-yi1,2, HE Xue-zhao1   

  1. 1. Laboratory for Environmental Change and Natural Disaster Research,Institute of Resources Science, Beijing Normal University, Beijing 100875, China;
    2. School of Earth and Environmental Sciences, Seoul National University, Seoul 151-742, Korea
  • Received:2001-07-10 Revised:2001-10-10 Online:2002-03-25 Published:2002-03-25
  • Supported by:

    National Key Project for Basic Research, No.G1998040900; National Natural Science Foundation of China, No.40105007

摘要:

西北太平洋副热带高压是影响我国夏季气候的一个非常重要的环流系统,本文主要分析了其年代际尺度的变化。发现在1979/1980年前后,其强度和范围发生了一次明显的年代际尺度的变化。1980年代以来,副高明显偏强,范围向西向南显著扩展。副高的年代际变化也对我国东部地区的气候产生了显著的影响。主要表现在近20多年来长江中下游地区夏季降水显著增加,华南地区夏季气温显著偏高,以及西太平洋20oN以南台风活动相对偏弱而20oN 以北洋面台风活动相对增强。副高的年代际变化与冬、春季赤道太平洋海表温度及同期热带印度洋海温有密切联系。

关键词: 西太平洋副热带高压, 年代际变化, 影响

Abstract:

Western North Pacific Subtropical High is a very important atmospheric circulation system influencing the summer climate over eastern China. Its interdecadal change is analyzed in this study. There is a significant decadal shift in about 1979/1980. Since 1980, the Western North Pacific Subtropical High has enlarged, intensified, and shifted southwestward. This change gives rise to an anti-cyclonic circulation anomaly over the region from the South China Sea to Western Pacific and thus causes wet anomalies over the Yangtze River valley. During the summers of 1980-1999, the precipitation is 63.9 mm above normal, while during 1958-1979 it is 27.3 mm below normal. The difference is significant at the 99% confidence level as a t - test shown. The southwestward expanding of the Western North Pacific Subtropical High also leads to a significant warming in the southern China, during the 1980-1999 the summer mean temperature is 0.37oC warmer than that of the period 1958-1979. The strong warming is primarily due to the clearer skies associated with the stronger downward air motion as the Western North Pacific Subtropical High expanding to the west. It is also found that the relative percentage of tropical cyclones in the regions south of 20oN has been decreasing since the 1980s, but that in the regions north of 20oN has been increasing during the same period. The Western North Pacific Subtropical High responds significantly to sea surface temperature of the tropical eastern Pacific with a lag of one-two seasons and simultaneously to sea surface temperature of the tropical Indian Ocean. The changes in the sea surface temperatures are mainly responsible for the interdecadal variability of the Western North Pacific Subtropical High.

Key words: Western Pacific Subtropical High, interdecadal change, climate change