不同辐射传输方案对中尺度降水影响的对比分析  

A STUDY ON IMPACTS OF DIFFERENT RADIATIVE TRANSFER SCHEMES ON MESOSCALE PRECIPITATIONS

作　　者：周广强[1] 赵春生[1] 丁守国[2] 秦瑜[1] 

机构地区：[1]北京大学物理学院大气科学系,北京100871 [2]中国科学院大气物理研究所,北京100029

出　　处：《应用气象学报》2005年第2期148-158,共11页Journal of Applied Meteorological Science

基　　金：国家重点基础研究发展规划项目"我国重大气候和天气灾害形成机理与预测理论研究"(G1998040911)项目资助。

摘　　要：在MM5非静力稳定中尺度气象模式中引进了建立在δ24流近似和相关2k分布基础上的对云水、雨水、冰晶和霰的辐射特性进行详细描述的辐射传输方案。新建立的辐射传输方案和MM5中原有的辐射传输方案在华南暴雨中的模拟结果相互比较,并与天气实况的对比表明辐射在中尺度暴雨中起着重要的作用;辐射传输方案对云辐射特性描述的准确程度对于地面降水影响是明显的;不同的辐射传输方案对地面降水的影响存在较大的差异,并且这些差异在白天比在夜间明显;辐射传输过程对地面降水影响的差异主要表现在降水中心上,而对降水的地理分布改变很小;相对而言,不同的辐射传输方案之间对短波描述的差异对地面降水的影响明显,而对长波描述差异的影响不大;新辐射传输方案能够在一定程度上改进MM5对中尺度降水的模拟能力。A radiative transfer scheme based on delta-4 stream, correlated-k distribution and with relative detailed cloud water, rain water, ice crystal and graupel radiative properties description, is employed into PSU/NCAR MM5. A study on impacts of different radiative transfer schemes on mesoscale precipitations is carried out using a case of South China Severe Storm in 1998. The calculations show that radiation process plays an important role in the mesoscale precipitations. The cloud radiative properties descriptive accuracy in the radiative transfer schemes influences the surface rainfall obviously. Different radiative transfer schemes result in different precipitation processes and the disagreement among the schemes in the daytime is much bigger than that at night. Radiative processes have distinct effect on the maximum rainfall centers, while little on the surface rainfall geographic distribution. The difference of the solar radiation calculation among the radiative transfer schemes causes more notable surface precipitation varieties than that of the longwave radiation. The employment of new radiative transfer scheme is successful and it improves the mesoscale precipitation simulation ability to a certain extent.

关 键 词：传输方案 降水影响 中尺度 对比分析 辐射特性 地面降水 MM5 气象模式 静力稳定 模拟结果 华南暴雨 传输过程 地理分布 模拟能力 对比表 冰晶 天气 

分 类 号：P461[天文地球—大气科学及气象学]