一次飑线过程的云微物理参数化方案数值试验及其成因分析  

Simulation experiments of cloud microphysical parameterization schemes on a squall line and its genesis analysis

作　　者：许广 费建芳[1] 黄小刚[1] 姜勇强[1] 程小平[1] 

机构地区：[1]解放军理工大学气象海洋学院,南京211101

出　　处：《气象科学》2017年第3期283-292,共10页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(41230421,41275099);国家重点基础研究发展计划(973计划)项目(2013CB430101)

摘　　要：利用WRF模式6种适合高分辨率且包含多种固态水成物粒子的云微物理参数化方案,分别对2012年5月16日江苏北部一次飑线过程进行数值试验,结果表明:LIN方案模拟的飑线回波反射率、强降水TS评分、结构和强度等均要优于其余5种微物理参数化方案。分析不同参数化试验结果中不同水成物粒子占比随时间的变化特征,并针对LIN方案采取敏感性试验和水成物转化微物理过程分析指出,在此次飑线过程中的各水成物粒子中,霰/雹粒子占比最大,是降水过程中最重要的粒子;地面降水直接来源是雨水,雨水主要来源于中层霰/雹粒子的融化,小部分来源于云水的自动转化;中层霰/雹粒子最主要来源是通过雨霰转化过程中的雨水撞冻冰雹微物理过程,其次是霰撞冻云水的微物理过程,而冰相物质雪晶和云冰的碰并、撞冻和自动转化过程微乎其微。Six cloud microphysical parameterization schemes of WRF model with high resolution and multiple moisture variables are conducted to numerically simulate a squall line in the northern Jiangsu on May 16, 2012. Results show that the echo reflectance, TS scores about heavy rain, structures and strength of the mimetic squall line simulated by LIN scheme are obviously superior to the other five cloud microphysical schemes. Moreover, the variation trend characteristics of moisture variables over time in different cloud microphysical parameterization schemes were analyzed and several sensitivity experiments in allusion to LIN scheme were carried out to clarify the microphysical transform process among different moisture variables. Experimental results show that the mixing ratio of graupel or hail is the maximum in all moisture variables and is the most important part of this squall line. Rainwater, originated mainly from the melting process of graupel and hail at the middle level and partly from cloud water, is the direct source of surface rain. The primary moisture variables, namely graupels or hails, are transformed from the conver- sion of raindrops to graupels or hail due to rain accretion. The accretion of drop water by graupels is the secondary contribution. As for the collection and accretion processes between cloud ice and snow as well as the autoconvertion, they are considered as negligible in the graupel and hail formation.

关 键 词：飑线 云微物理 参数化 WRF 水成物粒子 

分 类 号：P457.6[天文地球—大气科学及气象学]