近60年大连市日照时数变化规律及气象影响因子分析

Analysis on the Change Law and Meteorological Factor of Sunshine Duration in Dalian in Recent 60 Years

利用大连市基准站1951～2009年日照时数统计资料,对近60年大连日照时数年、季和月变化特征及气象影响因子进行了分析,并采用气候突变理论对日照时数进行检测分析。结果表明,近60年大连市年日照时数总体呈减少趋势,气候变化率为-3.31 h/a,年际变化幅度较大,峰值点(1978年)与谷点(2003年)相差681 h;日照时数存在明显的季节差异,各季日照时数年际变化减少的趋势为:秋季>夏季>冬季>春季,气候变化率分别为-1.18、-1.15、-0.91、-0.62 h/a;除3月份外,各月日照时数均呈减少趋势,其中10月的减少趋势较为显著,而3月份略有上升;日照百分率与总云量、相对湿度和大雾日数呈反相关;年日照时数在1983年附近急剧减少。

Based on the statistical data of sunshine duration from base station in Dalian City from 1951 to 2009,the annual,seasonal,and monthly variation of sunshine duration in recent 60 years were analyzed,as well as its meteorological factor,and sunshine duration was detected by means of climate mutation theory.The results revealed that annual sunshine duration in Dalian in recent 60 years showed decrease trend on the whole,and its climatic variation rate was-3.31 h/a,with larger annual variation,namely the difference between maximum value（1978） and minimum value（2003） reached 681 h;there was obvious seasonal variation in sunshine duration,with the order of autumnsummerwinterspring,and their climatic variation rate were-1.18、-1.15、-0.91、-0.62 h/a;except for March,sunshine duration in each month went down,especially October,while there was slight increase trend in March;sunshine percentage had inverse correlation relationship with total cloudiness,relative humidity and heavy fog days;annual sunshine duration reduced suddenly around 1983.