近50年贵港日照时数变化特征及影响因子分析

利用贵港市1963～2012年的日照、云量、雾、轻雾、降水等观测数据,采用统计学的方法,分析贵港日照时数的年、季、月变化特征,并分析其与云量、雾和轻雾日数、年降水量和降水日数的相关性.结果表明：贵港近50年的年日照时数总体呈减少趋势,其趋势变化率为-27.8h/10年;四季日照时数也均呈现下降特征,夏季的减少趋势最明显;月日照时数7月份最多,3月最少;云量、雾和轻雾日数的增加会导致日照时数的减少,年降水量和降水日数是影响日照时数的因素之一.

Variation Characteristics and Influence Factors of Sunshine Duration in Guigang in Recent 50 Years

According to the observation data of sunshine, cloudiness, fog, light fog and precipitation, etc. in Guigang in 1963-2012, the annual and seasonal and monthly variation characteristics of sunshine duration were analyzed by the statistical method and also its correlation with cloudiness, days of fog and light fog, days of precipitation and annual precipitation was studied. The results showed that the annual sunshine duration is decreased totally in Guigang during the last 50 years and its rate of changing trends is --27.Sh/10a. Also the seasonal sunshine duration is de- creased and it is the most obvious in summer.The monthly sunshine duration is the most in July and the least in March. The increase of cloudiness and days of fog and light fog leads to the decrease of sunshine duration. The annual precipitation and days of precipitation is one of the factors influencing sunshine duration.