Collaborative Research: The Impact of Lower Atmosphere Waves on Ionospheric Irregularities

合作研究：低层大气波对电离层不规则性的影响

• 批准号: 1640945
• 负责人: Timothy Fuller-Rowell
• 金额: $ 4万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-01-15 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1640945&HistoricalAwards=false
• 关键词: Collaborative; Research; Impact; Lower; Atmosphere

The overarching goal of this award is to address one of the long-standing problems in ionospheric physicws by determining the role of the lower atmosphere waves in the day-to-day variability of the development of F-region ionospheric irregularities. The lateral distribution of ionospheric plasma density is normally fairly uniform except for the irregularities that are similar in appearance to air bubbles in a liquid. The steep gradients on the edges of the bubbles disrupt radio wave signals, and so pose a significant hazard to a number of critical applications. Aviation and shipping are increasingly reliant on satellite navigation and thus, the disruption of navigation radio signals by these ionospheric irregularities poses a threat to passengers and crew, as well as the crafts themselves. Understanding the day-to-day variability of ionospheric irregularities has been one of the long-standing challenges in space physics. The proposed work describes how a whole atmosphere model (WAM) that covers the altitude region from the ground to the top of the atmosphere would be combined with an ionosphere plasma model that would be used to provide the background neutral winds and waves, plasma densities, and electrodynamic fields to drive a high-resolution ionospheric irregularity model. The goal is to determine what it is about the variability in the synoptic and large-scale background fields that is critical in explaining the variability of irregularity formation. A pilot study would be funded to carry out representative model calculations that would demonstrate the methodology of this unification of the thermosphere neutral atmosphere dynamical model with the Boston College plasma irregularity model. The broader impact of this study would be the potential development of a significant space weather forecasting capability based upon the tropospheric weather data imported into the whole atmosphere model formulation.The primary objective of the proposed work is to determine the characteristics and conditions of the background neutral atmosphere that lead to the initiation and development of ionospheric F-region irregularities at low latitudes. The work proposed would be based upon a collaboration between the University of Colorado (CU) and Boston College (BC) that would combine the large-scale whole atmospheric-ionosphere-electrodynamic modeling expertise at CU (Fuller-Rowell, Fang) with the BC group (Retterer, Groves, Valladares) that would provide the expertise regarding the irregularity modeling combined with observations from the LISN South American network developed under the leadership of Valladares. The motivation for this study is based upon the results of an ionospheric irregularity model simulation driven by the wind and wave fields derived by the CU whole atmosphere model with all the inherent variability associated with tropospheric dynamics. This simulation showed that irregularities grew naturally from the initial physical state without the need for additional artificial seeding. The proposed work builds upon recent findings that have exposed a strong connection between terrestrial and space weather.

该奖项的首要目标是通过确定低层大气波在f区电离层不规则性发展的日常变化中的作用，解决电离层物理学中一个长期存在的问题。电离层等离子体密度的横向分布通常是相当均匀的，除了在外观上类似于液体中的气泡的不规则性。气泡边缘的陡峭梯度会干扰无线电波信号，因此对许多关键应用构成重大威胁。航空和航运越来越依赖卫星导航，因此，电离层的不规则现象对导航无线电信号的干扰对乘客和机组人员以及飞机本身构成了威胁。了解电离层不规则性的日常变化一直是空间物理学的长期挑战之一。提出的工作描述了如何将覆盖从地面到大气层顶部高度区域的全大气模型（WAM）与电离层等离子体模型相结合，电离层等离子体模型将用于提供背景中性风和波、等离子体密度和电动力场，以驱动高分辨率电离层不规则性模型。目的是确定天气场和大尺度背景场的可变性，这对解释不规则形成的可变性至关重要。将资助一项初步研究，进行有代表性的模型计算，以证明将热层中性大气动力学模型与波士顿学院等离子体不规则模型统一起来的方法。这项研究的更广泛的影响将是潜在地发展一种重要的空间天气预报能力，这种能力是基于输入到整个大气模式公式中的对流层天气数据。提出的工作的主要目的是确定导致电离层f区不规则性在低纬度开始和发展的背景中性大气的特征和条件。提出的工作将基于科罗拉多大学（CU）和波士顿学院（BC）之间的合作，该合作将结合CU （Fuller-Rowell, Fang）和BC小组（Retterer, Groves, Valladares）的大规模全大气-电离层-电动力学建模专业知识，后者将提供有关不规则建模的专业知识，并结合在Valladares领导下开发的LISN南美网络的观测结果。这项研究的动机是基于电离层不规则模式模拟的结果，电离层不规则模式由CU全大气模式导出的风和波场驱动，具有与对流层动力学相关的所有固有变率。模拟结果表明，不规则从初始物理状态自然生长，无需额外的人工播种。这项提议的工作建立在最近的发现之上，这些发现揭示了地球和太空天气之间的紧密联系。