摘要
介绍了MM 5中的显式云物理方案 ,详细分析了Goddard、Reisner和Schultz方案的物理过程特点和存在的不足。这些云物理方案的多个微物理过程的描述不是很合理 ,对粒子的自动转化过程都采用阈值 ,且对雪、霰和雨的数浓度只进行诊断计算。Reisner方案的物理过程相对全面 ,预报量也较多 ,但仍存在一定的不足。通过对 1992年Andrew台风个例的模拟 ,发现尽管Reisner方案的物理过程比Goddard和Schultz方案全面 ,但模拟的台风眼最低气压和地面最大风速并没有优势。所以单一物理过程描述的改善不一定立即带来模式预报成效的提高 。
The various explicit microphysical schemes in MM5 are described, and especially the characteristics and shortages of Goddard, Reisner graupel and Schultz schemes are analyzed in detail. In these schemes, descriptions about some microphysical processes and variables are not quite reasonable and some of micro-processes need to be improved, such as ice nucleation, freezing of rain into graupels, auto-conversion and deposition of vapor into graupel, etc. A hurricane was simulated with Goddard, Schultz and Reisner graupel schemes. All the three schemes performed well in the structure and evolution simulation generally. The releases of phase-changing latent heat are sorted into six kinds, though they are highly sensitive to explicit schemes. The total effects of temperature caused by their latent heat are between 1.5 and 2.0 ℃.As for microphysical processes, the Reisner scheme is better than Goddard and Schultz schemes, but its simulations of the central pressure at the typhoon eye and the maximum surface wind speed are not as well as others, with the minimum pressure being much slower and the speed is higher than the observed. The simulation shows that a better cloud and precipitation scheme doesn't certainly improve the simulation results, and other physical and dynamics processes and initial input data may also affect the results.
出处
《气象科技》
北大核心
2004年第1期6-12,共7页
Meteorological Science and Technology
基金
973项目 (G19980 40 911)
"十五"国家科技攻关课题 2 0 0 1BA610A 0 6的资助
关键词
微物理过程
中尺度模式MM5
台风模拟
对比分析
MM5 explicit schemes, microphysical processes, hurricane simulation, comparison analysis
