区域气候模式中云-辐射-降水过程的超级参数化研究

Due to the complex terrain and monsoon climate character, there are unique features and significant spatial differences of cloud radiative forcing in East Asia. The shortage of the traditional cloud radiative and cloud precipitation parameterization Schemes to the sub-grid physical process are the main source of the uncertainty on the climate simulation performance. This project is to develop a regional climate model using a cloud-resolving model as a super parameterization of sub-grid cloud process. The super parameterized model , including multiscale modeling frameworks, has the role of explicit calculation method and unified physical process solution. Firstly, the regional climate model RegCM4 is chosen by the super parameterization method using the cloud resolving model( CRM ) to establish the SP-RegCM4 model; Secondly, the performance of the radiation flux and the adiabatic heating rate of SP-RegCM4 and RegCM4 is compared,considering the influence of cloud radiation process only. Response of vertical profiles of ground temperature and air temperature is also concerned; Finally, This project will use SP-RegCM4 to test the mutual feedback mechanism between the sub-grid cloud radiation and precipitation process on the atmospheric temperature and humidity structure and circulation features and its response to climate change.

季风气候叠加上复杂地形使东亚地区云过程表现出全球独特的特征和显著区域差异，传统的云辐射和云降水参数化方案对次网格物理过程描述的不足是东亚地区气候模拟性能不确定性的主要来源。本项目采用国际上最新发展的超级参数化的方法，将气候模式每个格点耦合云分辨模式来实现次网格云-辐射-降水过程的统一和显式计算，建立起具备多尺度模式框架的新一代区域气候模式。本项目首先将区域气候模式RegCM4以超级参数化的方法与改进后的CRM耦合建立SP-RegCM4模式；其次检验SP-RegCM4与单独的RegCM4在仅改变云辐射效应下辐射强迫通量和大气非绝热加热率模拟的性能，以及地面温度和气温垂直廓线的响应；最后探讨SP-RegCM4在同时改进云-辐射-降水过程时对大气温湿结构和环流场的互反馈机制及其气候响应。

针对区域气候模拟中云辐射和云降水参数化方案对次网格物理过程描述的不足的问题，本项目首先利用多源卫星观测的云产品数据进行对比分析，借助中国不同地区云宏微观特征进行空间和时间的技巧评分的定量分析，讨论了云量、云高、云水量和云滴数浓度等特征量的区域差异；其次本项目完成了云分辨模式CRM和区域气候模式RegCM4.6耦合，建立能显式计算次网格云辐射过程的超级参数化区域气候模式SP-RegCM；在充分分析我国不同地区不同等级降水强度和过程差异的基础上，检验了高分辨率区域气候模式云水时空特征模拟的不同影响因子，分析了不同分辨率下云辐射强迫通量和大气非绝热加热率的差异对气温和降水模拟的影响；最后探讨了模式中不同云微物理方案对大气温湿结构和环流场的互反馈机制及其气候响应。