梅雨锋暴雨过程潜热及反馈机理个例分析  

Analysis of Latent Heat and Its Feedback Mechanism during a Meiyu-Front Rainstorm

作　　者：张晓芳[1] 陆汉城[1] 

机构地区：[1]解放军理工大学气象学院,南京211101

出　　处：《气象科技》2006年第5期567-573,共7页Meteorological Science and Technology

基　　金：国家重点基础研究发展规划项目(2004CB418301)资助

摘　　要：在对2003年6月24-25日的一次江南北部梅雨锋暴雨过程进行合理模拟的基础上，应用模式输出资料，系统分析了暴雨过程中大尺度稳定凝结加热（Hs）及对流凝结加热（Hc）的时空分布特点以及其潜热在暴雨过程中的反馈作用。研究表明在这次暴雨过程中，主要以Hc为主，平均的Hs、Hc均主要分布在900～250hPa，最大值位于400hPa附近；在暴雨发展过程中，Hs、Hc随暴雨的增大而增大，且加热层次不断加深；去除潜热的“干”敏感性试验表明，潜热释放加热了深厚的大气层，使得高层加压辐散，暴雨北侧高空西北急流加强，低层减压辐合，暴雨南侧的低空西南急流加强，同时使得低层的切变线得以维持加强。Based on the reasonable numerical simulation for a Meiyu-front heavy rainfall during 24 - 25 June 2003 in the area south of the Changjiang River and the model products, an analysis is made of the temporal-spatial distribution characteristics of large-scale stable latent heat release （LHR） and convective latent heat release, as well as the feedback mechanisms of latent heat in the process of the rainfall event. The results show that the averaged convective LHR was greater than the large-scale stable LHR throughout the event, and both distributed between 900 and 250 hPa with the center at 400 hPa; both the large-scale stable LHR and convective LHR increased and extended deep with strengthening rainfall The ＂dry＂ experiment shows that LHR heated further the atmosphere and strengthened the upper-level high pressure and divergence, resulting in the enhancing of the upper-level northwest jet to the north; meanwhile, the effect of LHR weakened the lower-level low pressure, induced convergence, and strengthened the lower-level southwest jet to the south and the lower-level shear line.

关 键 词：潜热 大尺度稳定凝结潜热 对流凝结潜热 梅雨锋暴雨 反馈机制 

分 类 号：P458.121.1[天文地球—大气科学及气象学]