陕西省日照时数季节变化特征分析

利用1961-2010年陕西省95个气象站点的观测数据,采用Mann-Kendal非参数检验方法和EOF经验正交分解法,对陕西省近50 a来四季日照时数的变化特征进行了趋势性分析.结果表明,50 a来,陕西省日照时数的下降出现在夏季和冬季,其中夏季减少趋势通过了p=0.01的显著性检验.春季和秋季变化表现为上升趋势,但上升趋势不明显；四季日照时数的主要下降中心在延安地区中部和宝鸡地区西部,不同季节气候变异中心的位置会发生变化.

Variation Characteristics of Seasonal Sunshine Duration in Shaanxi Province

Based on the data observed at 95meteorological stations of Shaanxi Province from 1961to 2010,Mann-Kendall trend test and EOF analysis were used to study the tendency of the variation characteristicsof seasonal sunshine duration.Results showed that the seasonal sunshine duration decreased in summer andwinter in the last 50years,of which the decreased trend in summer passes significance test at p=0.01confidence level.The seasonal sunshine duration showed increased trends in spring and autumn,but the trendswere not significant in spring and autumn.The anomalous centers of the seasonal sunshine duration weremainly in the central Yan'an City and the west of Baoji City,and they were different in different seasons.