北京一次降雪的云物理过程作用模拟

Simulation of the Effect of Cloud Micro-physical Process on a Snow in Beijing

应用非静力平衡 MM5 V3模式对 2 0 0 1年 1 2月 7日一次北京降雪过程进行了数值模拟试验 ,对云和降水物理过程的作用进行了初步分析。试验结果表明 :本次降雪过程是从对流层上层形成冰核向下发展的 ,中高空的强低温和上升运动区与冰粒子及雪的分布基本吻合 ,为降雪的进一步发展提供了有利的条件。

By using non-hydrostatic model MM5 V3, a snow took place on dec.7,2001 in Beijing is simulated. The roles of cloud and micro-physical process are analyzed. The result indicates that ice nucleus formed in the middle troposphere and then developed downward. The strong low temperature region in the middle-upper level and upward moving region almost consist with the distribution of ice particle and snow, which offer favorable conditions for further development of the snow.