地理学报 ›› 2009, Vol. 64 ›› Issue (3): 278-288.doi: 10.11821/xb200903003

• 水分循环 • 上一篇    下一篇

近50 年四川盆地汛期极端降水事件的时空演变

胡豪然,毛晓亮,梁玲   

  1. 中国气象局成都高原气象研究所,成都610072
  • 收稿日期:2008-08-07 修回日期:2008-12-10 出版日期:2009-03-25 发布日期:2010-08-03
  • 作者简介:胡豪然,博士,副研究员,主要从事季风、海气相互作用研究工作。E-mail: hhr@pku.org.cn
  • 基金资助:

    中国气象局气候变化专项(CCSF2008-5);国家自然科学基金项目(40875060;40665003)

Temporal and Spatial Variations of Extreme Precipitation Events of Flood Season over Sichuan Basin in Last 50 Years

HU Haoran,MAO Xiaoliang,LIANG Ling   

  1. Institute of Plateau Meteorology,CMA,Chengdu 610072,China
  • Received:2008-08-07 Revised:2008-12-10 Online:2009-03-25 Published:2010-08-03
  • Supported by:

    The research item of the China Meteorological Administration,No.CCSF2008-5;National Natural Science Foundation of China,No.40875060;No.40665003

摘要:

利用四川盆地1961-2006 年145 个台站汛期的逐日降水资料, 分析了该地区汛期极端降水事件的时空演变特征, 结果表明: 该地区汛期极端降水事件的发生频次分布与降水量分 布差异较大, 由西向东呈阶梯状递减趋势; 川西高原与四川盆地之间以及盆地东西部之间的 反位相变化是川渝地区汛期极端降水事件发生频次最主要的两个空间异常模态; 该地区汛期极端降水事件发生频次的空间分布可以分为8 个区; 分别是四川盆地中部区、东部区、南部 区、西部区、川西高原西部区、中部区、川西南山地区和重庆东部区; 从长期变化趋势来看, 汛期极端降水事件发生频次除在四川盆地西部区和重庆东部区分别呈较弱的减少和增长趋势以外, 在其余各区的线性趋势都较为明显, 其中四川盆地东部区、川西南山地区、川西高原 西部和中部区表现为增长, 四川盆地中部和南部区表现为减少; 从气候因子分析看, 汛期西 太平洋副高位置的南北变化、东亚以及南亚季风的强弱变化分别对四川盆地东部区、中部区以及西部区的极端降水事件存在显著影响。

关键词: 四川盆地, 汛期, 极端降水, 时空演变特征

Abstract:

Based on the daily precipitation data of flood season in 1961-2006 from 145 stations over Sichuan Basin, we analyzed the temporal and spatial variations of extreme precipitation events. Results indicate that the extreme precipitation event frequency of flood season shows a gradual decreasing trend from west to east, which is remarkably different from the precipitation distribution. The anti-phase changes between Western Sichuan Plateau and Sichuan Basin, as well as west and east Sichuan Basin, are the main spatial models of extreme precipitation event frequency in flood season. The spatial distribution of extreme precipitation event frequency in flood season over Sichuan Basin can be identified into eight regions: central Sichuan Basin, east Sichuan Basin, south Sichuan Basin, west Sichuan Basin, west of Western Sichuan Plateau, central Western Sichuan Plateau, southwest Sichuan and east Chongqing. In terms of long-term trend, there is an apparent linear trend in extreme precipitation event frequency for all the regions, with the exception of a slight decrease and increase for west Sichuan Basin and east Chongqing. Among the eight regions, east Sichuan Basin, southwest Sichuan, western and central parts of Western Sichuan Plateau show an increasing trend, whileas central and southern Sichuan Basin show a decreasing trend. The fluctuating West Pacific Subtropical High and the varying intensities of East and South Asian monsoons have significant impact on extreme precipitation events over eastern, central and western parts of Sichuan Basin, respectively.

Key words: Sichuan Basin, flood season, extreme precipitation, temporal and spatial variations