2008年1月一次强降雪冰冻过程的数值模拟与分析  

Numerical Simulation on a Heavy Snowfall/Freezing Rain Process in January 2008

作　　者：朱坤[1,2] 刘华强[1] 丁守智 俞斌辉[3] 

机构地区：[1]解放军理工大学气象学院 [2]91867部队气象台 [3]94514部队气象台

出　　处：《暴雨灾害》2009年第2期104-111,共8页Torrential Rain and Disasters

基　　金：国家自然科学基金项目(40375027)资助

摘　　要：采用NCEP1°×1°再分析资料和常规观测资料,利用中尺度数值模式WRF对2008年1月25—29日发生在长江中下游地区的强降雪冰冻过程进行数值模拟,模拟结果显示:WRF模式可以较好地模拟出此次强降雪冰冻过程高低空环流形势演变特征以及降水雨雪带的分布。诊断分析结果进一步表明,西南低空急流对水汽的输送使得长江中下游地区成为很强的湿度区,为强雨雪冰冻的发生提供了充足的水汽条件。对降雪及冻雨的云微物理过程特征分析表明,中低空600—900hPa逆温层的存在与降雪及冻雨的发生密切相关,固态降水粒子经0℃以上逆温层融化后形成过冷却水降落至冷的地面形成冻雨,而雪的形成过程中逆温层的温度小于0℃。Based on the 1°×1° NCEP/NCAR reanalysis and daily observational datasets, the mesoscale model WRF was used to simulate a Heavy Snowfall/Freezing Rain Process occurred in the area of the middle and lower reaches of the Yangtze River from 25 to 29 January 2008. The results indicate that the WRF model can successfully simulate the characteristics of the circulation＇s evolution on high and low level. The distribution of precipitation area and precipitation cell can also be well simulated. Diagnoses of the output data show that the vapor transported by the Southwest low altitude jet flow made a humidity province in the middle and lower reaches of the Yangtze River basin and prepared sufficient moist conditions for the heavy snowfall/freezing rain. The analyses on the characteristics of the cloud microphysical processes of heavy snow/freezing rain show that there is an inversion layer from 600 to 900 hPa which is related closely with the heavy snow/freezing rain. The precipitation particles was melted by inversion layer with the temperature of above 0℃ into excessive cooling water which was quickly freeze up when it encountered cold surface whereas the temperature of melting layer is below 0 ℃ in the formation of snow.

关 键 词：暴雪 冻雨 数值模拟 云微物理过程 

分 类 号：P456.7[天文地球—大气科学及气象学]