img

官方微信

高级检索

中国沙漠 ›› 2009, Vol. 29 ›› Issue (1): 151-155.

• 天气与气候 • 上一篇    下一篇

用CEOF方法探讨形成西北地区沙尘暴天气的源地及传播特征

李艳春1, 冯建民1*, 赵光平1,2, 胡文东1

  

  1. 1.宁夏气象防灾减灾重点实验室, 宁夏 银川 750002; 2.江苏省气象灾害重点实验室(南京信息工程大学),江苏 南京 210044)
  • 收稿日期:2007-07-26 修回日期:2007-11-09 出版日期:2009-01-20 发布日期:2009-01-20

Study on Source and Moving of Sandstorm in Northwest China with CEOF Method

LI Yan-chun1, FENG Jian-min1, ZHAO Guang-ping1,2, HU Weng-dong1

  

  1. 1.Ningxia Key Laboratory of Meteorological Disaster Preventing and Reducing, Yinchuan 750002, China; 2.Jiangsu Key Laboratory of Meteorological Desaster (Nanjing University of Information Science & Technology), Nanjing 210044, China
  • Received:2007-07-26 Revised:2007-11-09 Online:2009-01-20 Published:2009-01-20

摘要:

利用西北地区311个气象站自1961—2003年43 a沙尘暴天气过程资料及近年来作为天气气候过程诊断分析的新工具之一(CEOF分析方法),分析研究形成西北地区沙尘暴天气的源区、传播方向及突变特征等。结果表明:①由沙尘暴天气日数及沙尘暴天气持续时间时变场CEOF展开的第一复主分量空间位相及空间振幅函数,对形成沙尘暴天气的源区有一个很好的反映,其空间位相函数的早位相中心与我国北方地区的主要沙漠区存在着很好的对应关系,并且沙尘暴天气持续时间时变场的CEOF展开项所包含的信息量更加丰富。②近43 a来西北地区沙尘暴天气日数总体上是在波动中不断减少的,其中前17 a间波动幅度相对较大,但基本没有出现明显的下降趋势,且属于沙尘暴天气的多发期,后26 a出现逐年下降的趋势。1977—1978年间是西北地区沙尘暴天气变化规律出现显著改变的时期。③1977年之前第二复主分量的时间位相序列为正位相,1978年以后出现位相上的突变,由正位相突变为负位相;第二复主分量的时间振幅在1975年之前偏高,1976年之后偏低;1976—1978年间西北地区沙尘暴天气日数由多发型转变为少发型。

关键词: 西北地区, 沙尘暴天气, CEOF方法

Abstract:

Based on sandstorm data documented by 311 meteorological stations from 1961 to 2003, the source, moving direction and abruptly changed characteristics of sandstorm in Northwest China were analyzed with CEOF method. The results show that ①the spatial phase and amplitude function of primary compound major component that expanded from the temporal variation fields of sandstorm days and duration by CEOF have close relation with the source of sandstorm, and there is also a close relation between the early phase center of phase function and major desert areas of northern China, and by comparison, the expanded elements of temporal variation CEOF of sandstorm duration has rich information; ②the sandstorm days in Northwest China decreased generally in recent 43 years, and in the first 17 years there was larger fluctuation amplitude but without remarkable decrease trend, it is the high frequency period of sandstorms, and in the next 26 years sandstorm days showed a decreasing trend year by year, the abruptly falling phase was in 1977—1978; ③the temporal series phase of the second compound major component kept positive before 1977 and changed to negative after 1978, the temporal amplitude of the second compound major component was higher before 1975 and lower after 1976, the period of sandstorm frequency changed from more into less was in 1977—1978.

Key words: Northwest China, sandstorm, CEOF method

中图分类号: