水资源与水工程学报2016，Vol.27Issue(2)：30-35,6.DOI:10.11705/j.issn.1672-643X.2016.02.06
1976-2010年榆林市降水时空变化趋势分析
Trend analysis of spatial-temporal change of precipitation in Yulin from 1976 to 2010
摘要
Abstract
The paper used monthly precipitation data from 109 stations over Yulin City from 1976 to 2010, applied Mann -Kendall test, empirical orthogonal function ( EOF) and wavelet analysis, and combined with the spatial analysis tools of Arcgis10 . 1 to analyze the spatial-temporal variability charac-teristics of precipitation in Yulin during last 35 years. The results indicate that the annual precipitation decreases from the southeast to the northwest, and the precipitation of annual, flood period and dry sea-son each site show different trends and annual precipitation shows a decreasing trend. There are two main types of precipitation in Yulin that are consistency of all precipitation and the northeast-southwest direc-tion type. Among these distribution types,the northeast-southwest precipitation are the typical precipita-tion type in Yulin, which is determined by the terrain conditions and climate factors. The time coeffi-cients each distribution type can describe time-varying characteristics of each type. From the fluctuation of time coefficient. there is a notable inter-annual oscillation of annual ,flood and dry season precipitati-on. The paper revealed the periodic variation of precipitation spatial structure by wavelet analysis. The re-sult showed that the period change of annual precipitation and precipitation of flood period is remarkable. There is not only a short period and high frequency variation of 6-7a, but also a low frequency variation of 20 a. There is only one periodic variation in dry season. This period characteristics may be related to the periodic variation law of the east Asian monsoon,which is also conformed to cycle variation discipline in large-Scale climate system.关键词
降水/时空分布/经验正交函数(EOF)/榆林市Key words
precipitation/spatial-temporal change/empirical orthogonal function ( EOF)/Yulin分类
建筑与水利引用本文复制引用
常肖杰,沈冰,黄领梅..1976-2010年榆林市降水时空变化趋势分析[J].水资源与水工程学报,2016,27(2):30-35,6.基金项目
国家自然科学基金重点项目(50939004) （50939004）
陕西省教育厅重点实验室项目(12JS067) （12JS067）
