%0 Journal Article %T 乌梁素海湖冰晴天反照率日变化特征的统计模型比较和分析 %T Comparison and analysis on the statistical models for the diurnal variations of lake ice albedo under clear skies of Lake Ulansuhai %A 汤明光,李志军,卢鹏,曹晓卫,李国玉,Lepparanta Matti,Arvola Lauri,石利娟 %A TANG,Mingguang %A LI,Zhijun %A LU,Peng %A CAO,Xiaowei %A LI,Guoyu %A LEPPARANTA,Matti %A ARVOLA,Lauri %A SHI,Lijuan %J 湖泊科学 %J Journal of Lake Sciences %@ 1003-5427 %V 32 %N 6 %D 2020 %P 1858-1868 %K 湖冰;太阳辐射;反照率;日变化;统计模型;乌梁素海;概率密度分布函数 %K Lake ice;solar radiation;albedo;diurnal variation;statistical model;Lake Ulansuhai;probability density distribution function %X 乌梁素海湖冰晴天反照率日变化具有双峰特征,利用当地太阳高度角同经纬度和儒历的关系,归一化到北京时,依此表达湖冰反照率日变化规律.基于具有指数函数形式的拉普拉斯、高斯、耿贝尔和柯西4种概率密度分布函数建立线性组合模型,对日出后到日落前太阳高度角大于5°时段内的反照率日变化数据进行拟合,发现拉普拉斯密度分布函数组合是最佳统计模型.它既能拟合太阳高度角大于5°时间范围内反照率日变化曲线的双峰特征,又能反映太阳高度角大于15°时间范围内反照率日变化曲线双峰之间的U型分布.该模型不仅形式简单,而且意义明确:尺度参数约为日长的一半,双峰位置与日出时刻关系密切;同时能体现2个反照率峰值的不对称性.为发展不同地区湖冰反照率日变化参数化方案奠定基础. %X Based on the features of diurnal variation of ice surface albedo in the Lake Ulansuhai, the relationship between solar elevation angle and geographic coordinates and Julian days, together with normalized time, to express the diurnal variations of the ice albedo. Linear combinations of four probability density distribution functions with exponential forms, including Laplace, Gauss, Gumbel, and Cauchy equations, were used to simulate the diurnal variations in observed ice albedo from sunrise to sunset with solar elevation angle more than 5°. The results reveals that the Laplace combined statistical model is the best fit to the observations. It can not only clearly show the double-peak distribution in the diurnal variation in ice surface albedo when the elevation angle is greater than 5°, but also express the U-type distribution between the two peaks as the elevation angle is more than 15°. This model has advantages of simple form in expression and clear physical meaning. The length parameter is close to half day, and the peak location is associated with the time of sunrise, and the asymmetry of the two peaks can be also shown. It provides a solid foundation for the parameterization schemes on the diurnal variations in lake ice surface albedo in different regions. %R 10.18307/2020.0625 %U http://www.jlakes.org/ch/reader/view_abstract.aspx %1 JIS Version 3.0.0