CEDAR: Traveling Ionospheric Disturbances (TIDs) Excited by Tropospheric Phenomena and their Effect on Plasma Instabilities

CEDAR：对流层现象激发的行进电离层扰动 (TID) 及其对等离子体不稳定性的影响

• 批准号: 1552161
• 负责人: Cesar Valladares
• 金额: $ 37.41万
• 依托单位: University of Texas at Dallas
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-15 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1552161&HistoricalAwards=false
• 关键词: CEDAR; Traveling; Ionospheric; Disturbances; TIDs

In this project, features in the Earth's ionosphere called traveling ionospheric disturbances (TIDs) will be studied by analyzing ground- and satellite-based measurements. The ground-based measurements include total electron current (TEC) measurements collected by a few hundred ground-based GPS receivers distributed across South and Central America and the Caribbean region in the LISN network (Low-Latitude ionospheric sensor network). It also includes ionosondes, Fabry-Perot Interferometers, and the incoherent scatter radars at Jicamarca and Arecibo. The outcomes of this research will be a better understanding of the variability and characteristics of medium-scale TIDs (MSTIDs) and TEC depletions during different ionospheric and thermospheric conditions. The study also aims to resolve whether there exists a link between tropical storms and the formation of MSTIDs. The occurrence of plasma irregularities poses a prominent natural hazard to communication, navigation and high precision pointing systems.The conjugate properties of MSTIDs and plasma structures seen at mid-latitudes under a variety of different ionosphere and thermosphere conditions and for magnetically quiet and active conditions will be investigated. Specifically, the following questions will be addressed: What is the control that the latitudinal variability of the plasma conductivity and the propagation direction of atmospheric gravity waves exert on the MSTIDs? What is the initiation mechanism of mid latitude depletions? Do MSTIDs map to conjugate locations during disturbed conditions? Can MSTIDs or TIDs influence the latitudinal (and then altitude) extension of equatorial plasma bubbles? During special events, such as large magnetic storms, TEC values collected by the majority of GPS receivers that exist in North America will be also be used to study poleward expansions of TEC depletions and MSTIDs. Electric fields and density observations gathered with several instruments on-board C/NOFS, DMSP and SWARM satellites will complement the observations.

在该项目中，将通过分析地面和卫星测量结果来研究地球电离层中称为电离层移动扰动的特征。地面测量包括由分布在南美洲、中美洲和加勒比区域的几百个地面全球定位系统接收器在低纬度电离层传感器网络中收集的总电子流测量。它还包括电离层探测仪、法布里-珀罗干涉仪以及在希卡马卡和阿雷西博的非相干散射雷达。这项研究的结果将更好地了解不同电离层和热层条件下中尺度TID（MSTID）和TEC耗尽的变化性和特征。该研究还旨在解决热带风暴和MSTID形成之间是否存在联系。等离子体不规则现象的出现对通信、导航和高精度指向系统构成了突出的自然危害，将研究在中纬度各种不同电离层和热层条件下以及在磁静和磁活跃条件下观察到的MSTID和等离子体结构的共轭特性。具体而言，将解决以下问题：什么是控制的等离子体电导率和大气重力波的传播方向的纬度变化施加在MSTID？中纬度枯竭的启动机制是什么？在扰动条件下，MSTID是否映射到共轭位置？MSTID或TID会影响赤道等离子体泡的纬度（然后是高度）延伸吗？在大磁暴等特殊事件期间，北美现有的大多数全球定位系统接收器收集的TEC值也将用于研究TEC耗尽和MSTID的向极扩展。用C/NOFS、DMSP和SWARM卫星上的几种仪器收集的电场和密度观测结果将补充这些观测结果。