中尺度对流复合体的降水特征和预报

MCC PRECIPITATION CHAPACTERSTICS AND PKEDnTION

利用增强红外卫星云图和逐时雨量观测资料，分析了中国大陆上中尺度对流复合体（ＭＣＣ）的降水强度、范围与ＭＣＣ云区的亮度温度值、不同亮温区云面积、云区面积随时间的变化率之间的关系。指出在ＭＣＣ生成一云发展到最强盛阶段之前，降水呈逐渐增加的趋势，最大降水出现在—５３℃、云面积达到最大之前１小时左右和ＭＣＣ中心最冷云顶面积达到最大的时候。出现在长江流域和华南地区的ＭＣＣ系统降水特征有显著的差异。最后根据ＭＣＣ云系演变规律提出了ＭＣＣ的降水预报思路。

In terms of enhanced satellite infrared cloud imagery and hourly rainfall,analysis is implemented of MCC(meso convective complex) over China mainland to reveal the relation ofthe precipitatinn vigor and fallout sector to the brightness temperature,cloud areas of differentbrightness and the timevarying change rate of the area inside MCC, Results show that rainfallincreases steadily from MCC foimation to preclimax of cloud,with the strongest intensityoccuring 1 h or so before the一53℃ cloud reaches its maximum and when the coldest cloud topslze does the same in the central MCC. Vast difference in the rainfall features is found betweenMCC's over the Changjiang basin of Central China and South China. In the end, someconsiderations are presented concerning the rainfall forecasting in the light of MCC cloudevolutinn.