Convective Cloud Systems in Climate Models

Randall, David A. Colorado State University（题目：气候模式中的对流云系统）PI及其团队提出了以下几个任务：(i)探索参数化垂直风切变对积云动能和积云质量通量关系的影响的可能性；（ii）研究凝结水负荷对对流有效势能（CAPE）的影响，并在积云参数化中实现改进的微物理参数化，探讨层状云量对积云参数化中使用的微物理参数化的敏感性；（三）实施最近提出的下沉气流参数化，并用它来探索对流下沉气流对地表通量的影响；（iv）实现更接近精确和内部一致的湿热力学过程表示，包括湿熵守恒和完整的能量循环；(v)发展“下一代”层状云量参数化版本，其中包括预测云分数变量、每个网格单元的晴空和多云部分的不同预测温度和水汽混合比，以及每个网格单元的晴空和多云部分的不同预测垂直速度；（六）测试CCM的层状云和对流参数化。这项工作很重要，因为它将增强对各种云参数化方案在GCM中的作用的理解。

Abstract ATM-9812384 Randall, David A. Colorado State University Title: Convective Cloud Systems in Climate Models The PI and his team propose to conduct several tasks: (i) to explore the possibility of parameterizing the effect of vertical wind shear on the relationship between the cumulus kinetic energy and the cumulus mass flux; (ii) to investigate the effects of condensed-water loading on the Convective Available Potential Energy (CAPE) and to implement improved microphysics parameterization in cumulus parameterization, to explore the sensitivity of stratiform cloudiness to the microphysical parameterization used in the cumulus parameterization; (iii) to implement a recently proposed downdraft parameterization and to use it to explore the effects of convective downdrafts on the surface fluxes; (iv) to implement a much more nearly exact and internally consistent representation of moist thermodynamic processes, including conservation of moist entropy and a complete energy cycle; (v) to develop a 'next generation' version of stratiform cloudiness parameterization with a prognostic cloud fraction variable, distinct prognostic temperatures and water vapor mixing ratios for the clear and cloudy portions of each grid cell and distinct prognostic vertical velocities for the clear and cloudy portions of each grid cell; and (vi) to test the stratiform cloud and convection parameterizations in the CCM. The work is important because it will enhance understanding of the role of various cloud parameterization schemes in GCM's.