Collaborative Research: Measurement and Analysis of Nocturnal Mesoscale Convective Systems and Their Stable Boundary Layer Environment During PECAN

合作研究：PECAN期间夜间中尺度对流系统及其稳定边界层环境的测量和分析

• 批准号: 1359709
• 负责人: Matthew Parker
• 金额: $ 20.41万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-15 至 2021-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1359709&HistoricalAwards=false
• 关键词: Collaborative; Research; Measurement; Analysis; Nocturnal

The Plains Elevated Convection At Night (PECAN) experiment will investigate the evolution of nocturnal mesoscale convective systems (MCSs) and convection and their interactions with the evolving nocturnal stable boundary layer (SBL) environment. This proposal addresses two primary goals of PECAN: 1) To characterize the transition from surface-based to elevated nocturnal MCS structure and the interaction of cold pools generated by MCSs with the nocturnal SBL, and 2) to determine how the organization and evolution of surface-based and elevated MCSs are influenced by the stable boundary layer and the vertical profile of wind and stability above the nocturnal low-level jet (NLLJ). To rectify the present paucity of detailed, integrated observations of nocturnal MCSs and their SBL environments, the project will observe nocturnal MCSs and convection with mobile ground-based radars, mobile sounding systems, and mobile mesonets in concert with other ground-based and airborne observing platforms during PECAN. Multi-radar syntheses, data assimilation, and modeling will provide the integrated analyses of these combined observations to evaluate the detailed internal structure of nocturnal MCSs and the impact of static stability, pre-existing boundaries, and wind shear on nocturnal MCS evolution processes.Intellectual Merit:This project emphasizes the tightly coordinated observation of nocturnal MCSs and their SBL environments with an array of multiple mobile Doppler and dual-polarimetric radars in conjunction with mobile soundings and surface in situ observing systems. These observations will be integrated to obtain 3-D airflow syntheses, precipitation fields, and thermal structure of MCSs and newly initiated convection and their environments. Mobile radars are essential as they can provide enhanced temporal and spatial resolution and low-level observations over any area within the PECAN domain. C-band radars, with their ability to both penetrate heavy precipitation and sense clear-air inflow, are required. The mobile C- and X-band dual-polarimetric radars will provide microphysical information beyond the typical operating ranges and below base-scan altitudes of the polarimetric WSR-88D radars. The mobile sounding and surface observations complement the radar wind measurements by providing unique buoyancy and shear profiles both within and outside of precipitation, thus resolving internal MCS dynamics and characterizing the SBL environment that interacts with the MCSs. These data, in combination with other PECAN data from fixed and mobile ground-based radar, profilers, mesonets, and aircraft, are essential for interpreting nocturnal MCS evolution with respect to in situ environmental conditions and for providing input and validation of cloud dynamical-microphysical model simulations of MCSs. The scientific objectives of this project are to: (i) document the internal structure and evolution of nocturnal MCSs and convection; (ii) establish the environmental ingredients and related physical mechanisms that control nocturnal MCS evolution; and (iii) test hypotheses concerning MCS dynamical microphysical forcing and MCS-environment interactions within detailed cloud-resolving models. The research conducted here will advance fundamental knowledge of the internal MCS dynamics and interactions with the SBL and will enable better representations of both within cloud-resolving models.Broader Impacts:Characterizing the morphology of nocturnal MCSs and the vertical profiles of temperature, humidity and winds ahead of and near the convective region in the cold pool are essential to helping improve the specificity and accuracy of diagnoses and short-term predictions of the geographical extent and duration of severe weather, heavy rainfall, flash flooding, and aircraft icing conditions. Additionally, these PECAN field observations will be essential for refining data assimilation systems and improving future operational numerical predictions of nocturnal MCSs and their SBL environments. The datasets collected here will also be used in university classes through graduate level. Several undergraduate and graduate students will be trained in the execution of a large atmospheric field campaign by being integrated into the data collection and post-field phase analysis. Lastly, the data collected here will be made available to other NSF and NOAA investigators identified as part of the PECAN project.

夜间平原高架对流（PECAN）实验将研究夜间中尺度对流系统（MCS）和对流的演变及其与夜间稳定边界层（SBL）环境的相互作用。该建议解决了PECAN的两个主要目标：1）表征从地面到高架夜间MCS结构的过渡以及MCS与夜间SBL产生的冷池的相互作用，以及2）确定地面和高架MCS的组织和演变如何受到稳定边界层以及夜间低空急流（NLLJ）上方风和稳定性的垂直廓线的影响。为了纠正目前缺乏详细的，综合的夜间MCS和他们的SBL环境的观察，该项目将观察夜间MCS和对流与移动的地面雷达，移动的探测系统，和移动的介子与其他地面和机载观测平台在PECAN。多雷达合成、数据同化和建模将提供这些组合观测的综合分析，以评估夜间MCS的详细内部结构以及静态稳定度、预先存在的边界和风切变对夜间MCS演变过程的影响。该项目强调了夜间MCS及其SBL环境的紧密协调观测，采用多个移动的多普勒和双多普勒阵列。极化雷达与移动的探测和地面原位观测系统相结合。这些观测结果将被整合，以获得三维气流合成，降水场，MCS和新发起的对流及其环境的热结构。移动的雷达是必不可少的，因为它们可以提供增强的时间和空间分辨率，并对PECAN域内的任何地区进行低水平观测。需要C波段雷达，因为它们既能穿透强降水，又能探测到晴空气流。移动的C波段和X波段双极化雷达将提供超出极化WSR-88 D雷达典型工作范围和低于基扫高度的微物理信息。移动的探空和地面观测通过提供降水内外独特的浮力和切变廓线补充了雷达风测量，从而解决了内部MCS动力学问题，并表征了与MCS相互作用的SBL环境。这些数据与来自固定和移动的地面雷达、剖面仪、中元网和飞机的其他PECAN数据相结合，对于解释夜间MCS相对于现场环境条件的演变以及提供输入和验证MCS的云动力微物理模型模拟至关重要。该项目的科学目标是：（一）记录夜间MCS和对流的内部结构和演变;（二）确定控制夜间MCS演变的环境成分和相关物理机制;（三）在详细的云解析模型内检验关于MCS动力微物理强迫和MCS-环境相互作用的假设。在这里进行的研究将推进内部MCS动力学和相互作用的基本知识与SBL，并将使两者在云解析models.Broader影响更好的表示：表征夜间MCS的形态和温度，湿度和风的垂直廓线提前和附近的冷池对流区是必不可少的，以帮助提高诊断和短期预测的地理范围和恶劣天气，暴雨，山洪暴发和飞机结冰条件的持续时间的特异性和准确性。此外，这些PECAN现场观测将是必不可少的，以完善数据同化系统，提高未来的业务数值预报的夜间MCS和他们的SBL环境。这里收集的数据集也将用于大学课程到研究生水平。将对几名本科生和研究生进行培训，使他们参与数据收集和实地后阶段分析，从而执行一项大型大气实地活动。最后，这里收集的数据将提供给其他NSF和NOAA调查人员，作为PECAN项目的一部分。

项目成果

Self-Organization and Maintenance of Simulated Nocturnal Convective Systems from PECAN

PECAN 模拟夜间对流系统的自组织和维护

• DOI: 10.1175/mwr-d-20-0263.1
• 发表时间: 2021
• 期刊: Monthly Weather Review
• 影响因子: 3.2
• 作者: Parker, Matthew D.