达坂城1959—2008年日照变化特征分析

Variation Characteristics of Sunshine during 1959-2008 in Dabancheng

利用达坂城气象站1959—2008年日照时数、日照百分率、总/低云量、≥0.1 mm降水日数、雾、沙尘暴、扬沙、浮尘等实测资料,运用线性分析方法对达坂城地区近50年来日照时数的变化特征进行分析。结果表明:日照时数呈波动式增加趋势,年日照时数的气候变化倾向率为37.62 h/10a,其中以春、夏季增长幅度为最快。日照时数和总、低云量及≥0.1mm降水日数之间具有很好的相关性,其中总云量的减小是影响日照时数变化的主要因素。沙尘暴、扬沙、浮尘天气由于呈减少趋势,且发生几率很小,对日照时数的变化没有影响。

Based on observation data of the sunshine hours,percentage of sunshine,total/low cloud cover,precipitation days with precipitation ≥0.1mm,fog,sandstorm,blowing sand,floating dust etc.in Dabancheng weather station from 1959 to 2008,this paper analyzed the variation characteristics of sunshine hours in recent 50 years with method of linear analysis.The results indicated that the sunshine hours revealed a fluctuated increasing trend with the climate tendency rate of annual sunshine hours 37.62 h/10a,thereinto it represented fastest increase in spring and autumn.There was close correlation between sunshine hours,total/low cloud cover and precipitation days with ≥0.1 mm precipitation.The decrease of total cloud cover was the main reason for the variation of sunshine hours there,whereas the increase of precipitation days and foggy days had not much impact on sunshine.Weather of dust storm,blowing sand and floating dust influenced the sunshine hours slightly since it showed a decreasing trend in recent 50 years with a very small annual probability of happening.