Collaborative Research: Investigations of Mesoscale and Microscale Processes in Extratropical Cyclones and Mesoscale Convective Systems

合作研究：温带气旋和中尺度对流系统中尺度和微尺度过程的研究

• 批准号: 0833828
• 负责人: Robert Rauber
• 金额: $ 127.68万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0833828&HistoricalAwards=false
• 关键词: Collaborative; Research; Investigations; Mesoscale; Microscale

The dynamic and microphysical processes that govern the spatial and temporal variability of precipitation within extratropical cyclones remain poorly understood. Variability in the location, type, and intensity of precipitation is often determined by precipitation banding and/or embedded convection, particularly in the northwest and warm frontal quadrant in cyclones where frontal structures and associated frontal circulations are modified by deformation flow. The Principal Investigators will execute a comprehensive field campaign and numerical modeling study that will address outstanding scientific questions targeted at improving understanding of precipitation substructures in the northwest and warm frontal quadrants of continental extratropical cyclones. In the course of this study the following questions will be addressed: 1) What are the predominant spatial patterns of organized precipitation substructures, such as bands and generating cells and how do they evolve? 2) How do frontal scale systems above and within the boundary layer such as warm fronts, trowals, cold fronts aloft, and occluded fronts relate to these precipitation substructures? 3) What are the thermodynamic and kinematic structures of these frontal systems including the distribution of moisture and vertical motion? 4) What instabilities and types of mesoscale forcing control the generation and evolution of precipitation substructures? 5) How do microphysical processes vary between the different precipitation substructures and what are the consequences? 6) Is instability triggered in ice-saturated ascent critical in some of these instances and is it through the release of the latent heat of deposition that instabilities can persist? The Principal Investigators will obtain and analyze detailed, high resolution observations of precipitation substructures using three mobile ground-based observing systems, the University of Alabama at Huntsville Mobile Integrated Profiling System, the Mobile Alabama X-band dual polarization radar, and the NSF/National Center for Atmospheric Research (NCAR) Mobile GPS Advanced Upper Air Sounding System, along with the NSF/NCAR C-130 Aircraft equipped with microphysical probes and the Wyoming Cloud Doppler Radar and Cloud Lidar. They will also simulate the precipitation substructures using the Weather Research and Forecasting Model at high horizontal and vertical resolution. The observations will provide the basis for the development of testable hypotheses that can be addressed systematically in the modeling studies. The field campaign (termed Profiling Of Winter Storms, or PlOWS) will have an education component, involving students from 9 universities with atmospheric science departments. Intellectual merit: The combined dynamical/microphysical observational strategy in conjunction with high resolution numerical modeling, will provide the basis for answering key scientific questions in a more complete and definitive way than heretofore possible. The new observational capabilities that will be applied in this research will provide fundamentally new information about the structure, dynamic and physical properties of these storms on scales never before observed. Broader impacts: Nationwide, nearly 7000 deaths, 600,000 injuries, and 1.4 million accidents per year are due to adverse road weather, mostly during winter, and costs associated with a single blizzard can range from $0.1M to $3.0B. The research will provide new insight concerning remote sensing of winter weather systems that can translate directly into better operational interpretation and observation strategies of winter weather mesoscale features. The research will contribute to a fundamental understanding of the relationship between the microphysical properties of clouds in winter cyclones and radar and lidar sensing of those properties. The modeling studies will determine if modeled precipitation substructures are consistent with observed features in winter storm systems and provide a better understanding of processes responsible for the occurrence of those substructures. Thus the findings will have direct application to forecasting. The education component, involving students from nine universities with atmospheric science departments, will contribute to undergraduate and graduate education and recruitment of new scientists into atmospheric field research.

控制温带气旋降水空间和时间变化的动态和微物理过程仍然知之甚少。降水的位置、类型和强度的变化通常由降水带和/或嵌入对流决定，特别是在气旋的西北和暖锋象限，其中锋面结构和相关的锋面环流被变形流改变。首席研究员将开展全面的实地考察和数值模拟研究，解决突出的科学问题，旨在提高对西北地区降水亚结构和大陆温带气旋暖锋象限的了解。 在本研究过程中，将解决以下问题：1）有组织的降水亚结构的主要空间模式是什么，例如带和生成细胞，以及它们如何演化？ 2) 边界层上方和内部的锋面尺度系统，如暖锋、抹锋、高空冷锋和遮挡锋，与这些降水亚结构有何关系？ 3）这些锋面系统的热力学和运动学结构是什么，包括水分的分布和垂直运动？ 4）什么不稳定性和中尺度强迫类型控制着降水亚结构的产生和演化？ 5）不同降水亚结构之间的微物理过程有何变化以及后果是什么？ 6）在某些情况下，冰饱和上升引发的不稳定是否至关重要？是否通过释放沉积潜热来维持不稳定性？首席研究员将使用三个移动地面观测系统（阿拉巴马大学亨茨维尔移动综合剖面系统、移动阿拉巴马 X 波段双极化雷达和 NSF/National大气研究中心 (NCAR) 移动 GPS 先进高空探测系统，以及配备微物理探测器和怀俄明州云多普勒雷达和云的 NSF/NCAR C-130 飞机激光雷达。他们还将使用天气研究和预报模型以高水平和垂直分辨率模拟降水子结构。观察结果将为可检验假设的发展提供基础，这些假设可以在建模研究中系统地解决。实地活动（称为“冬季风暴分析”或“PlOWS”）将包含教育部分，涉及来自 9 所大学大气科学系的学生。智力价值：动态/微观物理观测策略与高分辨率数值模型相结合，将为以比以往更完整、更明确的方式回答关键科学问题提供基础。这项研究将采用的新观测能力将提供有关这些风暴的结构、动态和物理特性的全新信息，其规模以前从未观测到。更广泛的影响：在全国范围内，恶劣的道路天气（主要是在冬季）每年造成近 7000 人死亡、600,000 人受伤和 140 万起事故，与一场暴风雪相关的损失可能从 10 万美元到 3.0 亿美元不等。 该研究将提供有关冬季天气系统遥感的新见解，可以直接转化为更好的冬季天气中尺度特征的操作解释和观测策略。该研究将有助于从根本上理解冬季气旋中云的微物理特性与雷达和激光雷达对这些特性的感测之间的关系。建模研究将确定模拟的降水子结构是否与冬季风暴系统中观测到的特征一致，并提供对导致这些子结构发生的过程的更好理解。因此，研究结果将直接应用于预测。教育部分涉及来自九所设有大气科学系的大学的学生，将为本科生和研究生教育以及招募新科学家进行大气领域研究做出贡献。