Collaborative Research: Instabilities, Dynamics, and Energetics accompanying Atmospheric Layering (IDEAL)

合作研究：伴随大气分层的不稳定性、动力学和能量（IDEAL）

• 批准号: 1632772
• 负责人: David Fritts
• 金额: $ 47.75万
• 依托单位: GLOBAL ATMOSPHERIC TECHNOLOGIES AND SCIENCES, INC.
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1632772&HistoricalAwards=false
• 关键词: Collaborative; Research; Instabilities; Dynamics; Energetics

The vertical structure of the free atmosphere under stable conditions from very low altitudes into the stratosphere and above is often characterized by thin, strongly stable, non-turbulent "sheets" separated by thicker, more weakly stratified, and often turbulent "layers". The occurrence and morphology of "sheet-and-layer" (S&L) structures in the free atmosphere are believed to be governed by larger-scale wind shears, gravity waves (GWs) at various frequencies, local S&L instability dynamics, turbulence and mixing, and their interactions.S&L structures have been known for several decades to play important roles in optical and radiowave propagation and in transport and mixing of heat, momentum, and constituents. There is also evidence that these small-scale flow features can have important implications for larger-scale dynamics, including instabilities and momentum transport accompanying GWs propagating to higher altitudes. However, little progress has been made in understanding the underlying dynamics or addressing the roles of instabilities and turbulence, the interactions among them, or the consequences of these flows for transport and mixing. In particular, the sources, morphologies, and statistics of intermittent turbulence events in stable stratification, and their dependence on environmental conditions remain to be defined observationally (e.g., instability character and statistics of S&L thicknesses, turbulence structure parameters and scales, and mechanical and thermal energy dissipation rates).Our lack of understanding of these dynamics to date can largely be attributed to observational and computational challenges in capturing the relevant atmospheric structures and dynamics with sufficient spatial and temporal resolution. The research program IDEAL, Instabilities, Dynamics, and Energetics accompanying Atmospheric Layering will conduct ground-based and in-situ measurements and associated modeling combined to quantify these processes and provide key insights into S&L dynamics and effects throughout the stratified atmosphere. The IDEAL will perform measurements either at Dugway Proving Ground (DPG) in Utah or at Camp Guernsey Joint Training Center (CG) in Wyoming, where restricted airspace is already assured.Intellectual Merit:For the first time, the dynamics underlying ubiquitous S&L structures in the free troposphere will be observed with multiple, coordinated, high-resolution, in-situ sensors together with the integrated sounding radar profiler and radiosondes from ~50 m to 4 km. Guidance and interpretation of the observations will be aided by high-resolution DNS, enabling identification of key dynamics and evaluation of theories and models of stratified turbulence, mixing, and transport.Broader Impacts:A more quantitative understanding of S&L dynamics in the stably stratified atmosphere will contribute to parameterization of their implications for transport and mixing and improve predictive capabilities of relevance to many research communities. These include applications as diverse as pollution and fugitive emission impacts, micro-climate forecasting, and aviation safety. The project will train two graduate students in state-of-the-art studies in atmospheric science, aerospace engineering, and computational fluid dynamics. Measurement technologies and techniques developed in this work will benefit future field research campaigns and regulatory compliance mandates.

在稳定条件下，从极低高度到平流层及以上的自由大气的垂直结构通常以薄的、强稳定的、非湍流的“片层”为特征，这些“片层”被较厚的、较弱的分层的且通常是湍流的“层”分隔开。自由大气中“层片”结构的形成和形态被认为是由大尺度风切变、不同频率的重力波、局部层片不稳定动力学、湍流和混合以及它们之间的相互作用所决定的，它在光和无线电波的传播以及热、动量和组分的传输和混合中起着重要作用。也有证据表明，这些小规模的流动功能可以有重要的影响，大规模的动态，包括不稳定性和动量输送伴随着全球Ws传播到更高的高度。 然而，在理解基本动力学或解决不稳定性和湍流的作用、它们之间的相互作用或这些流动对运输和混合的后果方面，进展甚微。特别是，稳定层结中间歇性湍流事件的来源、形态和统计，以及它们对环境条件的依赖性，仍然有待于在观测上加以定义（例如，不稳定性特征和统计S L厚度，湍流结构参数和尺度，以及机械和热能耗散率）。我们缺乏对这些动力学的了解，到目前为止，在很大程度上可以归因于观测和计算的挑战，捕捉相关的大气结构和动力学与足够的空间和时间分辨率。研究计划理想，不稳定性，动力学和能量学伴随大气分层将进行地面和原位测量和相关的建模相结合，以量化这些过程，并提供关键的见解SL动力学和影响整个分层的大气。IDEAL将在犹他州的Dugway试验场（DPG）或怀俄明州的根西岛营地联合训练中心（CG）进行测量，那里的空域已经得到了保证&。现场传感器连同综合探测雷达剖面仪和无线电探空仪从~50米到4公里。指导和解释的意见将有助于高分辨率DNS，使识别的关键动力学和评价的理论和模型的分层湍流，混合，和transport.Broader影响：一个更定量的了解SL动力学在稳定的分层大气将有助于参数化的运输和混合的影响，提高预测能力的相关性，许多研究社区。这些应用包括污染和无组织排放影响、微气候预测和航空安全等多种应用。该项目将培养两名研究生，从事大气科学、航空航天工程和计算流体动力学方面的最新研究。这项工作中开发的测量技术和方法将有利于未来的实地研究活动和法规遵从性任务。

项目成果

Numerical Simulations of High‐Frequency Gravity Wave Propagation Through Fine Structures in the Mesosphere

• DOI: 10.1029/2018jd029746
• 发表时间: 2019-08
• 期刊: Journal of Geophysical Research: Atmospheres
• 作者: Tyler S. Mixa;D. Fritts;T. Lund;B. Laughman;Ling Wang;L. Kantha

On the Performance of the Range Imaging Technique Estimated Using Unmanned Aerial Vehicles During the ShUREX 2015 Campaign

关于 ShuUREX 2015 活动期间使用无人机估计的距离成像技术的性能

• DOI: 10.1109/tgrs.2017.2772351
• 发表时间: 2018
• 期刊: IEEE Transactions on Geoscience and Remote Sensing
• 影响因子: 8.2
• 作者: Luce, Hubert;Hashiguchi, Hiroyuki;Kantha, Lakshmi;Lawrence, Dale A.;Tsuda, Toshitaka;Mixa, Tyler;Yabuki, Masanori
• 通讯作者: Yabuki, Masanori

Comparisons between high-resolution profiles of squared refractive index gradient M2 measured by the Middle and Upper Atmosphere Radar and unmanned aerial vehicles (UAVs) during the Shigaraki UAV-Radar Experiment 2015 campaign

2015 年信乐无人机雷达实验活动期间中高层大气雷达和无人机测量的平方折射率梯度 M2 高分辨率剖面之间的比较

• DOI: 10.5194/angeo-35-423-2017
• 发表时间: 2017
• 期刊: Annales geophysicae
• 影响因子: 1.9
• 作者: Luce, H.