西北地区太阳辐射量变化的研究

根据西北地区１５个日射甲种站观测的近３０年来到达地面的太阳辐射量观测资料，经方差分析表明：太阳散射辐射量有２／５的地区在增加，２／５的地区在减少，还有１／５的地区太阳散射、直接辐射量在时间变化上差异都不明显；太阳直接辐射量有４／５的地区在显著减减少；太阳总辐射量几乎各地都在减少，这种减少趋势大致从１９７８年开始，并且用太阳辐射倾向率的形式概括出３种太阳辐射量季节变化类型。

RESEARCH ON THE VARIATION OF SOLAR RADIATION IN NORTHWEST CHINA

The variation of solar radiation in Northwest China during the recent 30 years is ana lyzed with variance technique and significance test (Fa = 0. 05 ), The results show that, in Northwest China, the diffuse solar radiation increases in 2/5 ragions, such as in Urumqi,Geermu, Yinchuan, Lanzhou, Ruoqiang, Minqin, etc., whereas decreases in 2/5 regions,such as in Altay, Kuqa, Hotan, Yining, Turpan, Xining, etc., and in other 1 /5 ragions,there is no obvious variation with time, such as in Hami, Dunhuang, etc. Direct solar radia tion decreases obviously in 4/5 regions of the whole region, and global solar radiatlon de creases obviously in almost whole Northwest China since 1978. In addition, three typical types of seasonal variation of solar radiation are obtained: (1)Diffuse solar radiation increas es in every season; (2)diffuse solar radiation decreases in every season ; (3)diffuse solar radia tion decreases in winter and increases in summer, The direct and global solar radiation, how ever, decrease obviously in every season, which is a common feature in Northwest China.