Based on CloudSat and CALIPSO data from 2007 to 2010,the cloud vertical structure (CVS) over Northeast China (39°-53°N,119°-135°E) was analyzed.At first,the precipitation flag of CloudSat was validated by surface observation.Based on the validation,the parameters of CVS,especially that of precipitation cloud and non-precipitation cloud,were analyzed.The results show that the distribution of cloud fraction profile is bimodal and shows significant diurnal and seasonal variations.Single-layer cloud is the main type over Northeast China and most precipitation is generated by such cloud which is the main target of artificial rainfall enhancement.Most precipitation cloud is nimbostratus of low,cold,ice or mixed phase.Two-layer precipitation cloud is dominated by high-low or high-medium cold cloud,and most of the high cloud is cirrus or altostratus of ice phase while the low cloud is dominated by nimbostratus,stratocumulus or cumulus of mixed or ice phase.Significant differences of CVS between precipitation and non-precipitation are found.Precipitation is more likely to occur in the cloud with low cloud base (CB),thick cloud depth (CD),and thin cloud interlayer thickness (CIT).Meanwhile,the CB temperature of precipitation cloud is higher and varies significantly with seasons.%利用2007-2010年CloudSat和CALIPSO卫星资料,首先通过大量个例分析并结合地面逐小时降水量观测资料验证CloudSat卫星识别降水云指标的合理性.在此基础上,统计分析了东北地区(39°～53°N、119°～135°E)的云垂直结构参数,着重分析了降水云系和非降水云系的垂直结构差异和季节差异.结果表明:东北地区云量廓线呈双峰分布特征,有明显的昼夜及季节差异.东北地区以单层云为主,降水也主要产生于这类云系,是东北地区人工增雨作业的主要对象.单层降水云以低云、冷云、冰云或混合云为主,主要云类别是雨层云.双层降水云以高低云或中低云配置为主,且都为冷云;高层以冰云为主,主要类型是卷云和高层云;低层以混合云或冰云为主,主要类型是雨层云、层积云、积云.降水云系与非降水云系存在显著的垂直结构差异,双层云的降水由低层产生.云底高度较低、云体较厚且夹层厚度更薄的云易产生降水.同时,降水云云底温度更高,分布呈现出季节差异.
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