Aerosol radiative effects remain one of the largest uncertainties in climate assessments due to the large spatial and temporal variations of aerosol amount and optical properties. In recent years, very few researches focus on the aerosol optical properties over central China with high aerosol loading. To assess the temporal variation and spatial distribution of columnar aerosol optical properties over Hubei Province, the aerosol products obtained from the Collection 6 Moderate resolution Imaging Spectroradiometer (MODIS) sensor (MOD04_L2) from 2002 to 2016 were analyzed. The high and low value areas of AOD were similar to the AMC in four seasons, and this distributions were positively related with terrain feature and population density in Hubei Province. While, the FMF showed the opposite distributions compared to AOD. The AOD presented obviously seasonal characteristics, with lower values in fall and winter and higher values in spring and summer. The AMC in summer was the lowest, which indicated that the high values of AOD in summer were caused by the hygroscopic growth of aerosol. In spring, AOD and AMC were highest over the central and southern Hubei Province due to dust from local and long distance transportation. The highest value of FMF was observed in the western Hubei during summer; the lowest value was located in Wuhan and Jingzhou during winter, which was related to the increase of coarse mode particles emitted by human activities and the occasional dusty day. In Wuhan, AOD increased year by year before 2008, but decreased after 2010 (-0.05 per year). The monthly average of FMF and AOD were highest in June 2010.%气溶胶存在巨大时空变化特征,对其辐射效应的评估仍存在很大的不确定性,有效的评估很大程度地依赖于气溶胶光学特性.华中地区气溶胶水平长期以来居高不下,然而对这一区域的气溶胶光学特性研究存在很大的缺口.利用MODIS C6数据集的气溶胶产品(MYD04_L2)对湖北省2002—2016年气溶胶光学特性的时空变化情况进行分析,并提取武汉周边地区气溶胶光学参数及大气柱气溶胶质量浓度,对其时间变化特征进行分析.结果表明,整个湖北省气溶胶光学厚度(AOD)、细粒子比(FMF)、气溶胶柱质量浓度(AMC)均呈现显著的高低值分界线,与湖北东西部的地势和人口密集程度差异有关.其中,AOD与AMC高低值的范围相似,而FMF的高、低值区与AOD、AMC分布相反.AOD季节上呈现春夏高、秋冬低的态势;然而,夏季AMC值最小,这表明夏季AOD高值是由气溶胶吸湿性增长作用增强引起的.受局地扬沙和远距离沙尘输送影响,春季鄂中南部存在远高于其他三季的大范围AOD和AMC高值区.FMF高值出现在夏秋两季,与二次气溶胶增长有关;最低值出现在冬季,武汉及荆州周边地区FMF值最低,受人为排放的粗模态粒子增加和偶发性沙尘天气共同作用.武汉地区气溶胶光学厚度和柱质量浓度呈逐年下降趋势,其中AOD在2008年以前逐年上升,而在2010年以后以每年0.05的幅度下降;FMF和AOD月平均最大值均出现在2010年6月.
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