冰雪晶形态对混合相云微物理量分布影响的分档模式研究

针对现有MMM(Microphysical method of moments)冰雪晶分档方案在冰相过程数值处理方面的不完备性，拟在原分档方案的基础上，结合云物理学最新的研究成果，发展一个考虑冰晶形状，可以较为精细的描述不同形状冰晶粒子凝华、丛集过程，并可较为详细地描述冰雪晶到霰的渐进性转化过程的混合相云多阶矩分档方案，以提高现有MMM分档方案对上述微物理过程的模拟能力，为云微物理研究提供一个新的实用工具；进而利用所发展的模式，对已有的飞机垂直探测所获取的云微观资料(各类冰雪晶数浓度，含水量及粒子谱型等)进行数值模拟，通过敏感性实验，研究冰雪晶形态对混合相云冰液相分布及转化的影响，并对比分析验证新分档方案的模拟能力。

Given the inherent shortcoming of the present MMM (Microphysical Method of Moments) bin scheme in discribing mix-phase cloud, the purposes of this project are to develop a noval mixed phase cloud bin scheme and provide a state-of-the-art tool for the study of cloud microphysics. By combining with latest research results, this mixed phase cloud bin scheme is expected to describe the detailed microphysical processes, including deposition, aggreation of ice crystals with different shapes, and the progressive conversion of rimed snow to graupel. Consequently, the ability of the numerical simulations of cloud microphysics in terms of riming, sublimation as well as aggregation can be improved by means of such scheme. Moreover, studies can be accomplished by comparing of simulations with in-situ aircraft observations (liquid water content, ice number concentration, ice water content as well as the size spectra) , in order to investigate the effects of ice habits on vertical distributions of microphysical properties as well as phase partitioning in mixed clouds. The achievements of this project are expected toimprove the scientific basis of cloud microphysics.