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利用1984～2009年国际卫星云气候学计划(ISCCP) D2数据集的平均云量(MCA)资料,提取了中亚地区不同区域平均云量的时间序列特征,并利用平均云量时间序列平稳性、季节性等特征将中亚地区云量划分为3类:月平均云量时间序列季节性非平稳类型、月平均云量时间序列普通非平稳类型和月平均云量时间序列平稳类型.从分类结果看,中亚地区云量总体呈现非平稳特征.月平均云量时间序列季节非平稳类型云量主要集中在哈萨克斯坦和新疆地区,月平均云量时间序列普通非平稳类型云量主要分布在哈萨克斯坦北部和中部偏东一直延伸到新疆的条带地区,月平均云量时间序列平稳性类型云量主要分布在阿姆河流域.从平均云量结果看,中亚地区1984～2009年的总体平均云量为64.69％,最高为1984年的66.50％,最低为1999年的62.38％,最高和最低平均云量之间相差4.12％.中亚地区平均云量变化趋势为先下降后上升,并在中间发生了一次震荡,但总体呈现出下降的趋势.“,”Using the Mean Cloud Amount (MCA) data of 1984～2009 annual International Satellite Cloud Climatology Project (ISCCP) D2 data set,time series features of mean cloud amount in different regions of Central Asia are extracted by time series analysis method.Using the time series stationary features of mean cloud amount,cloud amount in Central Asia is divided into two categories:the monthly mean cloud amount time series stationary type and non-stationary type,and then the non-stationary type is divided into two categories:the monthly mean cloud amount time series ordinary non-stationary type and seasonal non-stationary type by time series seasonal features of mean cloud amount.At last,mean cloud amount in Central Asia is divided into three categories:the monthly mean cloud amount time series stationary type,namely,stationary type,the monthly mean cloud amount time series ordinary non-stationary type,namely,ordinary non-stationary type,and the monthly mean cloud amount time series seasonal non-stationary type,namely,seasonal non-stationary type.The classification results show that the seasonal non-stationary type accounts for 62.37 ％ of the study area,the ordinary non-stationary type and stationary type respectively account for 31.18％ and 6.45％ of the study area respectly.The overall cloud amount in Central Asia shows non-stationary characteristics.The seasonal non-stationary type areas are mainly concentrated in Kazakhstan and Xinjiang region,the ordinary non-stationary type areas are mainly in the northern and central east Kazakhstan extending to a strip region of Xinjiang and the stationary type areas are mainly in Amu Darya River Basin.The mean cloud amount results show that,the overall mean cloud amount in Central Asia is 64.69 ％ from 1984 to 2009 with a maximum of 66.50％ in 1984 and a minimum of 62.38％ in 1999.The difference between maximum and minimum mean cloud amount is 4.12％.The mean cloud amount in Central Asia has a downward trend at first,and then has upward trend.There was a shock in the middle,but the overall shows a downward trend.