CEDAR: Plasma Altitude Distributions Associated with Storm Enhanced Densities (SEDs) Caused by Competing Mechanisms

该项目的重点是确定由于电离层和磁层之间强烈的等离子体质量耦合而产生的风暴增强密度羽流的原因。它将有效地将最先进的模型和测量相结合，从而提高我们对电离层和等离子体层之间耦合的科学理解。主要成果将是改进基于物理的地球-S高层大气模型，以及改进对电离层和等离子体层风暴时间响应的预测能力。这项研究的主要目的将是确定背景中性密度、中性风和电场在等离子体高度变化中的相对作用以及在不同SED中观测到的总电子含量(TEC)的变化。这项研究将利用最先进的电离层-等离子体层第一原理模型、一套中性大气模型和磁层-电离层-热层耦合模型的组合，以描述各种驱动因素和响应/反馈。需要回答的具体问题是：1)SED内的等离子体高度分布是如何随风暴的大小、持续时间和阶段而演变的？2)在决定与SED相关的等离子体高度分布的演变及其局部时间相关性方面，原位化学过程和动力过程的相对贡献是什么？3)SED内的等离子体高度分布如何依赖于经度、季节和半球的不对称性？来自NSF资助的SuperDARN和非相干散射雷达项目的数据以及GPS-TEC和航天器数据将与先进的建模相结合，以最大限度地提高科学回报。该项目将包括一个暑期REU学生的参与。

This project is focused on determining the causes of Storm Enhanced Density (SED) plumes resulting from strong plasma mass coupling between ionosphere and magnetosphere. It will improve our scientific understanding of the coupling between ionosphere and plasmasphere by effectively combining state-of-the-art models and measurements. The major outcome will be improved physics-based models of the Earth?s upper atmosphere and improved predictive capabilities of the storm time response of the ionosphere and plasmasphere. The main goal of this research will be to determine the relative roles of the background neutral density, neutral wind and electric field in the plasma altitude variation and observed variations in the magnitudes of total electron content (TEC) in different SEDs. This study will utilize a combination of the state of the art first principles models of the ionosphere-plasmasphere, a suite of neutral atmosphere models, and the coupled Magnetosphere-Ionosphere-Thermosphere model, in order to describe the various drivers and response/feedback. The specific questions to be answered are: 1) How do the plasma height distributions within SEDs evolve depending on the magnitude, duration, and phase of the storms?; 2) What is the relative contribution of the in-situ chemical vs. dynamical processes in determining the evolution of the plasma height distributions associated with SEDs and its local time dependence?; 3) How do the plasma height distributions within SEDs depend on the longitude, season and hemispheric asymmetry? Data from the NSF-funded SuperDARN and incoherent scatter radar projects with GPS-TEC and spacecraft data will be combined with advanced modeling to maximize scientific return. The project will involve participation of a summer REU students.