Collaborative Research: CEDAR--Quantifying Ion Drifts in the Mid-latitude Ionosphere and Their Coupling to the Neutral Atmosphere

合作研究：CEDAR——量化中纬度电离层中的离子漂移及其与中性大气的耦合

• 批准号: 1552247
• 负责人: J Michael Ruohoniemi
• 金额: $ 9.96万
• 依托单位: Virginia Polytechnic Institute and State University
• 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: 2016-04-01 至 2019-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1552247&HistoricalAwards=false
• 关键词: Collaborative; Research; CEDAR; Quantifying; Ion

The Coupling, Energetics, and Dynamics of Atmospheric Regions (CEDAR) program is a broad-based, community-guided, upper atmospheric research program. It is aimed at understanding the behavior of atmospheric regions from the middle atmosphere upward through the ionized upper layers of the atmosphere and into outer space in terms of coupling, energetics, chemistry, and dynamics on regional and global scales. The mid-latitude ionosphere serves as the intermediary between the active ionospheres of the polar and equatorial regions, but it has not been studied very thoroughly. This Collaborative CEDAR award involving University of Texas at Dallas, Virginia Tech University, and the University of Colorado is aimed at developing the first quiet-time empirical model of the ionosphere electric field distribution to fill in the necessary ground truth needed to produce a true understanding of the global dynamics of the ionosphere. The research effort would use 15 years of Air Force Defense Meteorological Space Plasma (DMSP) measurements of ion zonal flow speeds in the mid-latitude ionosphere to construct an empirical model of mid-latitude ionospheric quiet-time electric fields. This data set would be supplemented by ion drift data obtained from the mid-latitude SuperDARN sites. This database would be made available to outside users, and thus, would be a valuable ionospheric community resource. Following the completion of the development of the quiet time model, observations from storm times will be compared to predictions based upon application of the new quiet time model. The determined differences would be analyzed within the guidance and context of the CTIP (Coupled thermosphere ionosphere plasmasphere)-RCM model runs to understand the underlying physical mechanisms causing the observed variability relative to the baseline model established, to quantify the magnitude and extent of storm-time disturbances, and finally, to quantify the coupling of the mid-latitude ion drifts to the neutral atmosphere and the transfer of energy between the polar and equatorial regions. Finally, making use of nearly two decades of DMSP data to understand and develop empirical models goes to the heart of one of the fundamental challenges of the CEDAR Aeronomy program, which is to quantify a baseline model of mid-latitude electric fields. Consequently, the question of variability as a function of solar phase, geomagnetic activity, and dynamical coupling to the lower atmosphere and to the magnetosphere regions can be more carefully assessed. The results achieved would be of great interest and use to the ionosphere and thermospheric modeling community and also relevant to the CEDAR mission of "understanding the fundamental properties of the space-atmosphere interaction region (SAIR); identify the interconnected processes that define the SAIR's global behavior, evolution, and influence on the Sun-Earth system". The main goal of this project is to quantify the response of the ionosphere relative to direct, spectrally separated measurements of solar extreme ultraviolet (EUV) radiation from the TIMED and SDO spacecraft. This approach constitutes an immense improvement over previous studies based on proxies. The C/NOFS and DMSP spacecraft at a range of altitudes will provide corresponding measurements of ionospheric parameters. This dataset, spanning more than a solar cycle, allows for the use of advanced statistical analysis techniques and will be used together with the SAMI-2 model to address outstanding science questions related to understanding the ionospheric response to solar EUV variability. Interesting questions to be investigated include the relative importance of and interaction between the responses in the neutral and ionized components of the upper atmosphere.

大气区域（CEDAR）计划的耦合，能量和动力学是一项基于广泛的，社区引导的大气层研究计划。它的目的是了解大气中间大气的行为，从大气的离子上层向上，而在区域和全球尺度上的耦合，能量，化学和动力学方面，进入了外太空。中纬度电离层充当极性区域和赤道区域的活性电离层之间的中介，但尚未对其进行深入研究。这项合作雪松奖涉及得克萨斯大学达拉斯大学，弗吉尼亚理工大学和科罗拉多大学，旨在开发电离层电场分配的第一个安静的经验模型，以填补对电离层全球动态所需的必要基础真理。研究工作将使用15年的空军防御气象空间等离子体（DMSP）测量中纬度电离层中离子区域流量速度的测量，以构建中纬度电离层安静的电场的经验模型。该数据集将通过从中纬度超darn位点获得的离子漂移数据来补充。该数据库将提供给外部用户，因此将是宝贵的电离层社区资源。安静时间模型的开发完成后，将将风暴时间的观察结果与基于新的安静时间模型的应用进行比较。确定的差异将在CTIP的指导和背景下进行分析（热层电离层等离子球）-RCM模型运行以了解相对于建立的基线模型的潜在物理机制，以量化风暴时间扰动的大小和整个环境，从极性和赤道区域。最后，利用将近二十年的DMSP数据来理解和开发经验模型，这是雪松航空计划的基本挑战之一的核心，该计划是量化中纬度电场的基线模型。因此，可以更仔细地评估可变性作为太阳相，地磁活性和动力耦合和磁层区域的动态耦合问题。获得的结果将引起电离层和热层建模社区的极大兴趣和使用，并且还与Cedar任务相关，以了解“了解太空 - 大气相互作用区域（SAIR）的基本特性（SAIR）；确定定义Sair的全球行为，演变，并对日落越野系统的影响的相互联系的过程”。 该项目的主要目的是量化电离层相对于直接分离的太阳极端紫外线（EUV）辐射的响应，从定时和SDO航天器的辐射。这种方法构成了基于代理的先前研究的巨大改进。在一系列高度处的C/NOF和DMSP航天器将提供相应的电离层参数测量值。该数据集超出了太阳周期，允许使用先进的统计分析技术，并将与SAMI-2模型一起使用，以解决与理解对太阳能EUV变异性的电离层响应有关的杰出科学问题。要研究的有趣的问题包括上层大气中中性和电离成分中反应之间的相对重要性和相互作用。