改则强降水过程分析

Analysis of Heavy Rainfall Process in Gerze

利用Micaps常规观测资料、NCEP的1°×1°逐6 h再分析资料和FY2E云图资料,运用天气学原理等方法,对2016年7月28日改则发生的强降水过程的天气系统演变、水汽、热力和动力条件等进行分析。结果表明,巴尔克什湖附近的低压槽底部冷空气下渗到改则地区形成弱的高原槽是此次强降水产生的影响系统;此次降水时间短,雨量大;包括涡度、散度、垂直速度和水汽通量散度在内的物理量在强降水发生后才出现有利条件。对流云团B靠近测站时,降水已经开始,云团还在改则上空维持其强度时,强降水已经结束;改则站的降水发生时并不是云顶亮温最低时,更像是由于产生了降水而造成的TBB下降。

Using the Micaps conventional observation data,NCEP 1° × 1° by 6 h reanalysis data and FY2E cloud data,the weather system evolution,water vapor,heat and power conditions and other aspects of the heavy rainfall process on July 28,2016 were analyzed by the method of weather science and other methods. The results showed that the cold air of the bottom of the low pressure trough near the Barr Kashmir Lake infiltration into Gerze region to form a weak plateau trough,which was the impact system of heavy rainfall. The time of this precipitation was short,the precipitation was large. The physical quantities（ including vorticity,divergence,vertical velocity and water vapor flux divergence）occurred favorable conditions after heavy rainfall occurring. The precipitation had begun when convective clouds B near the station,the cloud was still over the maintaining its strength over Gerze,the heavy rainfall had ended. When the precipitation occurs in Gerze station,it was not the lowest of cloud top brightness temperature,and the decreasing of TBB was more due to the precipitation.