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Firstly,presents an assessment of CALIPSO observation by comparing to the ground based lidar CE 370-2.Then CALIPSO level 2 aerosol profile data from June 2006 to October 2011 is used to study the vertical distribution and seasonal variation of aerosols over SACOL.Four types of aerosols are observed over SACOL: dust (with an occurrence frequency of 55.3% among all subtypes of aerosols),polluted dust (27.3%),smoke (15.5%) and clean continental (1.8%).Aerosols are uniformly distributed from ground to 2 km above,anthropogenic aerosols decrease while natural aerosols relatively increase from 2 to 4 km,dust dominates in the heights of 4~6 km,while only polluted dust is observed in the layer of 6~8 km,no aerosol is observed above 8 km.In spring,dust occurs frequently over SACOL (90.6%); in summer,the occurrence frequency of smoke almost equals that of polluted dust and these two types of aerosols occur almost at the same height bin; in autumn,local dust and smoke are mixed from ground to 2 km; in winter,dust is observed in the height bin of 2~6 km.Dust is mostly observed in spring and winter within 6 km; smoke is mostly observed in summer and autumn within 4 km; polluted dust has much the same occurrence frequency in summer,autumn and winter,mostly below 2 km and can reach the height bin of 6~8 km.