2006年7月3日豫北区域性大暴雨数值模拟与诊断分析  

Numerical Simulation and Diagnostic Analysis of Regional Rainstorm Process in Northern Henan on 3 July 2006

作　　者：马月枝[1] 沈桐立[1] 王新红 宋培玲 田春娜 

机构地区：[1]南京信息工程大学大气科学学院,南京210044 [2]新乡市气象局,河南新乡453003

出　　处：《气象与环境科学》2008年第3期54-60,共7页Meteorological and Environmental Sciences

基　　金：中国气象科学研究院灾害天气国家重点实验室基金项目(2006LASW01)资助

摘　　要：利用1°×1°NCEP再分析资料和WRF中尺度数值模式对2006年7月3日豫北区域性大暴雨过程进行了数值模拟,并结合常规观测资料和中尺度模式输出结果对这次大暴雨过程进行了初步分析。结果表明:这次过程是在西风槽与副热带高压共同影响的天气形势下,由中低层切变线、地面倒槽等影响系统共同作用的结果;大暴雨发生在高温、高湿、强不稳定的有利环境中;副高边缘西南急流将海上充沛的水汽输送到豫北地区并在此汇集,造成豫北上空强降水期间稳定维持深厚的湿层;同一地区高低层出现的正负涡度柱、散度柱耦合结构和剧烈的上升运动,导致不稳定能量快速释放,产生大暴雨;垂直螺旋度的分布和强度变化对暴雨落区和强度变化有很好的指示性。With the 1 ° × 1 °NCEP reanalysis data and WRF mesoscale model, a numerical simulation is carried out to reveal the formation mechanism of the heavy rainstorm in northern Henan on 3 July 2006. At the same time, a preliminary dynamic and thermodynamic diagnostic analysis of the rainstorm system is made using conventional observations and WRF model outputs. It is found that the heavy rainstorm is affected directly by the Western Pacific Subtropical High （WPSH） when it interacts with westerly trough in addition to the shear line of middle and lower layer and inverse trough of surface. The heavy rainstorm is generated in favorable synoptic conditions, such as warm and moist environment and convectively instable stratification etc. Abundant water vapor over ocean is transferred towards continent by the southwest jet and the water vapor fluxes are converged over northern Henan and result in the constant deep saturation vapour there during the heavy rainfall period. Positive and negative vorticity columns all appearing in high and low level, coupling structure of divergence columns and strong ascending motion lead to fast release of instability energy and rainstorm ultimately. The spatial distribution of vertical helicity can confirm the situation of effecting system and precipitation area; the intensity of vertical helicity is proportional to precipitation intensity.

关 键 词：大暴雨 WRF 数值模拟 诊断分析 垂直螺旋度 

分 类 号：P458.121.1[天文地球—大气科学及气象学]