We use two cloud screening methods—the clustering method and the multiplet method—to process the measurements of a sun photometer from March 2020 to April 2021 in Shouxian. The aerosol optical depth (AOD) and Angström parameters α and β are retrieved; variation characteristics and single scattering albedo are studied. The results show that: (1) The fitting coefficient of AOD retrieved by the two methods is 0.921, and the changing trend is consistent. The clustering method has fewer effective data points and days, reducing the overall average of AOD by 0.0542 (500 nm). (2) Diurnal variation of AOD can be divided into flat type, convex type, and concave type. Concave type and convex type occurred the most frequently, whereas flat type the least. (3) During observation, the overall average of AOD is 0.48, which is relatively high. Among them, AOD had a winter maximum (0.70), autumn and spring next (0.54 and 0.40), and a summer minimum (0.26). The variation trend of AOD and β is highly consistent, and the monthly mean of α is between 0.69 and 1.61, concerning mainly continental and urban aerosols. (4) Compared with others, the single scattering albedo in Shouxian is higher, reflecting strong scattering and weak aerosol absorption.

中文翻译：

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寿县太阳光度计气溶胶光学深度分析

我们使用两种云筛选方法——聚类方法和多重方法——来处理 2020 年 3 月至 2021 年 4 月在寿县的太阳光度计测量结果。检索气溶胶光学深度 (AOD) 和 Angström 参数 α 和 β；研究了变化特性和单次散射反照率。结果表明：（1）两种方法反演得到的AOD拟合系数为0.921，变化趋势一致。聚类方法的有效数据点和天数较少，使 AOD 的整体平均值降低了 0.0542（500 nm）。(2) AOD的日变化可分为平坦型、凸型和凹型。凹型和凸型出现频率最高，而扁平型最少。(3)观察时，AOD的总体平均值为0.48，比较高。他们之中，AOD 具有冬季最大值 (0.70)、秋季和春季次之（0.54 和 0.40）以及夏季最小值 (0.26)。AOD和β的变化趋势高度一致，α的月均值在0.69～1.61之间，主要涉及大陆气溶胶和城市气溶胶。(4) 与其他地区相比，寿县的单次散射反照率较高，反射强散射，气溶胶吸收弱。