Using a Regional-scale Model to Analyze the Scale Dependence of Convection, Cloud Microphysics, and Fractional Cloudiness

使用区域尺度模型分析对流、云微物理和分数云量的尺度依赖性

• 批准号: 0717597
• 负责人: Laura Fowler
• 金额: $ 35.37万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0717597&HistoricalAwards=false
• 关键词: Using; Regional; scale; Model; Analyze

Intellectual Merit: This research focuses on the analysis of the spatial scale dependence of convection, cloud microphysics, and fractional cloudiness, from the results of short-term experiments with varying resolutions using the Weather Research Forecast (WRF) model. First, the Principal Investigator will implement a set of unified prognostic parameterizations that simulate moist convective and cloud microphysics processes, from cloud resolving to low resolution regional modeling scales. Second, a series of numerical experiments will be run with decreasing horizontal resolutions with the aim to define the spatial scale at which parameterized convection and fractional cloudiness are both needed. The numerical experiments will be run over the Continental United States for which observations and small-scale forecasts are abundant and readily available. The research aims at quantifying the impact of horizontal resolution on the simulations of cloud systems in WRF, using parameterizations of moist processes which interact between each other in a consistent manner. Using a high resolution numerical experiment as a reference, the research addresses the questions 1) What is the horizontal resolution at which parameterized convection becomes needed, and how to best simulate interactions between convection and cloud microphysics processes?; and 2) What is the horizontal resolution at which parameterized fractional cloudiness becomes needed, and how to best simulate the cloud amount as a function of cloud microphysics sources and sinks? Broader Impacts: The research addresses the need of the WRF Users' community by providing a set of parameterizations of moist processes that were consistently developed, and can be used at different horizontal scales.

智力优势：本研究重点分析对流、云微物理和分度云量的空间尺度依赖性，基于使用天气研究预报（WRF）模式的不同分辨率的短期实验结果。首先，首席研究员将实施一套统一的预测参数化，模拟湿润对流和云微物理过程，从云解析到低分辨率区域建模尺度。其次，在水平分辨率逐渐降低的条件下进行一系列数值实验，以确定对流参数化和分数云量都需要的空间尺度。数值实验将在美国大陆进行，那里的观测和小尺度预报丰富而容易获得。该研究旨在量化水平分辨率对WRF中云系统模拟的影响，使用湿润过程的参数化，这些过程以一致的方式相互作用。以高分辨率数值实验为参考，研究了以下问题：1)在多大的水平分辨率下需要参数化对流，以及如何最好地模拟对流与云微物理过程之间的相互作用；2)需要参数化分数云量的水平分辨率是多少，如何最好地模拟云量作为云微物理源和汇的函数？更广泛的影响：该研究通过提供一组湿过程的参数化来满足WRF用户社区的需求，这些过程是一致发展的，可以在不同的水平尺度上使用。