近61年承德市日照时数变化特征及影响因素分析

Analysis on Variation Characteristics and Influencing Factors of Sunshine Hours in Chengde City in Recent 61 Years

利用承德国家基本气象站1961—2021年的气象观测资料,采用线性趋势分析、滑动平均、距平法和t检验等方法,对承德市近61年日照时数的变化及影响因素进行分析。结果表明:近61年承德市年日照时数呈显著减少趋势,四季日照时数也呈减少趋势,以夏季减少趋势最为显著,因此日照时数的减少主要体现在夏季的减少。年日照时数与低云量和相对湿度呈显著负相关,低云量和相对湿度的显著增加是年日照时数和四季日照时数减少的主要原因。

Based on the meteorological observation data of Chengde National Basic Meteorological Station from 1961 to 2021,the changes and influencing factors of sunshine hours in Chengde City in recent 61 years were analyzed by linear trend analysis,moving averaging,distance leveling method and t-test were.The results showed that in recent 61 years,the annual sunshine hours in Chengde City showed a significant decreasing trend,and the sunshine hours in four seasons also showed a decreasing trend,with most significant decreasing trend in summer.Therefore,the decrease of sunshine hours is mainly reflected in the decrease in summer.The annual sunshine hours were significantly negatively correlated with low cloud cover and relative humidity.The significant increase of low cloud cover and relative humidity was the main reason for the decrease of annual sunshine hours and seasonal sunshine hours.