初始云滴浓度（CCN）对对流性降水作用的数值试验

本文利用一个二维滞弹性非静力平衡云模式1]，选择三个典型个例，就初始云滴浓度（CCN）对对流性暖雨和冷雨过程的效应进行了数值试验。模拟结果表明：初始CCN对对流性降水影响较大。对暖雨过程而言，随着初始CCN的增大，地面累积降水量减弱；对冷雨过程而言，增大初始CCN，可削弱对流强度，减少地面累积降雹量，延缓液态水到达地面的时间，但最终增强了地面累积液态降水量。并且分析了初始CCN导致暖雨和冷雨过程这种差别的原因。

THE NUMERICAL TEST OF INITIAL CLOUD DROPLET CONCENTRATION (CCN) EFFECT ON CONVECTIONAL PRECIPITATION

A two-dimensional anelastic nonhydrostatic equilibrium cloud model has been used to simulate initial cloud droplet concentration(CCN) effect on convectional warm rain and cold rain processes, and three typical samples have been used to simulate test in this paper. The result indicates: initial CCN has great influence on convectional precipitation. In case of warm rain processes, the bigger initial CCN,the smaller surficial accumulation precipitation; In case of cold rain processes,the bigger initial CCN,the weaker convectional intensity,and the less surface accumulated hail, and the increase of initial CCN delayed the time of liquid water to surface. But at last,the increase of initial CCN enhanced surface accumulated liquid precipitation.And this paper also analysed the reason of these results.