Impacts of Representing Heterogeneous Distribution of Cloud Liquid and Ice on Phase Partitioning of Arctic Mixed‐Phase Clouds with NCAR CAM5
Impacts of Representing Heterogeneous Distribution of Cloud Liquid and Ice on Phase Partitioning of Arctic Mixed‐Phase Clouds with NCAR CAM5
复制标题
DOI：
10.1029/2019jd030502
复制
发表时间：
2019-12
期刊：
影响因子：
--
通讯作者：
Meng Zhang;Xiaohong Liu;M. Diao;J. D’Alessandro;Yong Wang;Chenglai Wu;Damao Zhang;Zhien Wang;S. Xie
中科院分区：
文献类型：
--
作者：
Meng Zhang;Xiaohong Liu;M. Diao;J. D’Alessandro;Yong Wang;Chenglai Wu;Damao Zhang;Zhien Wang;S. Xie
在这项研究中，我们使用社区大气模式第5版进行敏感性实验，以了解通过对Wegener-Bergeron-Findeisen（WBF）过程进行不同扰动来表示云液体和冰之间的非均匀分布对混合相云中相分配的影响。在两个实验中，使用了基于口袋结构假设的扰动因子和从高性能环境研究仪器机载平台（HIAPER）极对极观测（HIPPO）活动中得出的部分均匀云体积。或者，在WBF过程的计算中使用质量加权假设，以模拟由于非均匀分布而导致的混合相云中的非饱和区域的外观。模型实验在单柱和天气预报模式下进行测试，并根据美国能源部（DOE）大气辐射测量（ARM）计划的混合相北极云实验（M-PACE）现场活动和长期地面多传感器测量的数据进行评估。模式结果表明，WBF过程的扰动可以显着修改模拟的北极混合相云的微物理特性。模拟云水相分离的改善往往是线性成正比的扰动幅度，这是在三个不同的敏感性实验中应用。云的宏观物理性质，如云的分数和低层混合相云的出现频率，对扰动幅度的敏感性低于云的微物理性质。此外，这项研究表明，云水凝物之间的非均匀分布应一致地处理所有云微物理过程。模式的垂直分辨率对于混合相云中液态水的维持也很重要。
In this study, we conduct sensitivity experiments with the Community Atmosphere Model version 5 to understand the impact of representing heterogeneous distribution between cloud liquid and ice on the phase partitioning in mixed‐phase clouds through different perturbations on the Wegener‐Bergeron‐Findeisen (WBF) process. In two experiments, perturbation factors that are based on assumptions of pocket structure and the partial homogeneous cloud volume derived from the High‐performance Instrumented Airborne Platform for Environmental Research (HIAPER) Pole‐to‐Pole Observation (HIPPO) campaign are utilized. Alternately, a mass‐weighted assumption is used in the calculation of WBF process to mimic the appearance of unsaturated area in mixed‐phase clouds as the result of heterogeneous distribution. Model experiments are tested in both single column and weather forecast modes and evaluated against data from the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Program's Mixed‐Phase Arctic Cloud Experiment (M‐PACE) field campaign and long‐term ground‐based multisensor measurements. Model results indicate that perturbations on the WBF process can significantly modify simulated microphysical properties of Arctic mixed‐phase clouds. The improvement of simulated cloud water phase partitioning tends to be linearly proportional to the perturbation magnitude that is applied in the three different sensitivity experiments. Cloud macrophysical properties such as cloud fraction and frequency of occurrence of low‐level mixed‐phase clouds are less sensitive to the perturbation magnitude than cloud microphysical properties. Moreover, this study indicates that heterogeneous distribution between cloud hydrometeors should be treated consistently for all cloud microphysical processes. The model vertical resolution is also important for liquid water maintenance in mixed‐phase clouds.