J4 ›› 2006, Vol. 24 ›› Issue (3): 35-41.

• 论文 • 上一篇    下一篇

祁连山近45 a年降水异常的气候特征

张小明1,2魏锋2陆燕3   

  1. 1.中国气象局兰州干旱气象研究所,甘肃省干旱气候变化与减灾重点实验室,甘肃兰州730020;2.甘肃省定西市气象局.甘肃定西743000;3.山西省运城市陆县气象局,山西平陆044300
  • 收稿日期:2006-04-30 修回日期:2006-05-20 出版日期:2006-09-30 发布日期:2006-09-30
  • 作者简介:张小明(1969一),男,甘肃岷县人,工程师,主要从事天气气候研究及业务工作.E_mail; qxjZXM@SINA.com.
  • 基金资助:

    国家科技攻关计划:西部开发科技行动”重大项目“祁连山空中云水资源开发利用研究”( 2004BA901A16 -02-02)资助

Climatic Characteristics of Annual Precipitation in Recent 45 Years in Qilian Mountain

ZHANG Xiao-ming1,2, WEI Feng2, LU Yan3
  

  • Received:2006-04-30 Revised:2006-05-20 Online:2006-09-30 Published:2006-09-30

摘要:

利用祁连山地区17个测站1960 ~2004逐日降水资料,统计逐年不同量级的雨日数及年降水量,对年总降水量标准化后进行经验正交展开(EOF)和旋转经验正交展开(REOF),研究其异常的空间结构及时间演变规律。结果表明,祁连山地区年降水与不同量级雨日数的气候平均分布具有地理分布上的相似性。无论年降水还是不同量级的雨日数,同纬度地区西侧明显多于东侧,祁连山东段多于西段,等值线呈西北一东南走向。年降水异常在空间上主要表现为整体一致的变化特点,其次表现为东西相反的变化趋势。旋转载荷向量场(RLV)反映出4个异常型,即祁连山西段北坡区、祁连山东段区、祁连山中西段南坡区,祁连山中段北坡区。近45 a,祁连山西段北坡区年代际变化幅度明显,其他各区年代际变化幅度相对较小。小波分析发现,各区年降水周期变化并不一致,体现出祁连山地区年总降水的复杂性。

关键词: 祁连山, 年降水, 气候特征, 旋转经验正交函数

Abstract:

The yearly rainy days with different rainfall level and annual precipitation were obtained by using the daily precipitation data (1960-2004) of 17 stations in the Qilian Mountain. By means of EOF and REOF analysis on normalized annual precipitation, the abnormal spatial distribution and the time evolvement of annual precipitation there were investigated. Results show that the climate average distributions of annual precipitation and different level rainy days were similarity in geographical distribution. Both the annual precipitation and the different level rainy days were evidently more in the west side than that in the east side of the same latitude area, and more in the east section than that in the west section of the Qilian Mountain, and the isoline presented the direction of northwest to southeast. The spatial anomaly of the annual precipitation  characterized the coincident variability in the whole area at first, and then the adverse trends in the east and the west part. The rotated loading vectors reflected 4 anomaly modes of the north slope of the west section, the east section, the south slope of the west and middle section, and the north slope of the middle section of the Qilian Mountain. In recent 45 years, the decadal change in precipitation was obvious in the north slope of the west section and relatively small in the other three areas. Wavelet analysis shows that the precipitation period changes were different in four areas, and that means the complexity of the annual total precipitation over the Qilian Mountain.

Key words:

中图分类号: