GEM: Fundamental Properties of Dawnside Auroral Polarization Streams and Their Role in Magnetosphere-Ionosphere Instabilities and Dramatic Events

这项工作主要关注在地球上层大气(或电离层)中流动的一种独特的强电场现象，称为黎明赛德极光极化流(DAP)。DAP是近地空间环境能量循环的重要组成部分，与导致该系统剧烈能量释放的不稳定性有关。频繁发生的DAP可以显著改变电离层温度，从而改变电离层的组成和密度，从而影响低空航天器的阻力和无线电波传输的闪烁。该项目旨在了解DAP的形成和后果，将为近地空间环境的高级建模和空间天气预报提供关键信息。这项受资助的工作将促进早期职业科学家(PI)和非常早期职业生涯的女性研究人员的发展。它还将让对空间物理感兴趣的本科生作为志愿者，并申请研究课程学分。这个项目涉及极光现象，自然会吸引普通大众。产品中的适当材料将通过教育和公共推广工作传达给公众(包括K-12学生)。在极光椭圆形区域1洋流部分内向南延伸的强烈电场和相关的向东流动被称为Dawnside极光极化流(DAPs)。DAP的强电场可以显着改变磁层-电离层对流和高能粒子漂移，加热电离层和热层。本项目旨在确定DAP的基本性质及其影响，包括DAP在不同条件下如何变化，导致这些变化的原因，以及它们在导致戏剧性M-I事件的不稳定中的作用。该团队将使用低空航天器观测(Sarm和DMSP)来测量磁场矢量和东西向流，从中他们可以用自动化方法识别FAC结构和DAP。将这些方法应用于约20年的数据，该团队将进行全面的统计研究来回答这些问题。研究结果将为DAPs的产生机制及其对M-I系统对流、加热和不稳定的影响提供重要信息。因此，研究结果将为M-I能量循环提供重要的启示。鉴于DAP的频繁出现和强度及其与电离层电导率重大变化的关系，这些发现可能会对M-I-T模型产生革命性的影响。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This work focuses on a unique phenomenon of a strong electric field that flows in Earth’s upper atmosphere (or ionosphere), called Dawnside Auroral Polarization Streams (DAPS). The DAPS is an essential component of the energy circulation of the near-Earth space environment and is related to the instabilities responsible for dramatic energy releases in the system. Occurring frequently, DAPS can significantly modify the ionosphere temperature and thus its composition and density, which impact the drag of low-altitude spacecraft and the scintillation of radio wave transmission. Aiming at understanding the formation and consequences of DAPS, this project will provide crucial information for advanced modeling of the near-Earth space environment and space weather prediction. This funded work will promote the development of an early-career scientist (the PI) and a very early-career female researcher. It will also involve undergraduate students interested in space physics as volunteers and for research course credit. This project involves auroral phenomena, so it naturally appeals to the general public. Appropriate materials from the products will be conveyed to the public (including K-12 students) via education and public outreach efforts.The strong southward electric field and associated eastward flow that extends within the Region 1 current portion of the auroral oval are referred to as the Dawnside Auroral Polarization Stream (DAPS). A DAPS’ strong electric field can significantly modify magnetosphere-ionosphere convection and energetic particle drift and heat the ionosphere and thermosphere. This project aims to determine fundamental DAPS properties and their impacts, including how DAPS vary under different conditions, what contributes to these variations, and their role in instabilities responsible for dramatic M-I events. The team will use low-altitude spacecraft observations (Swarm and DMSP) to measure a magnetic field vector and east-west flow, from which they can identify FAC structures and DAPS with automated methods. Applying these methods to ~20 years of data, the team will conduct comprehensive statistical studies to answer the questions. The research results will provide crucial information on DAPS’ generation mechanism and its impacts on the M-I system's convection, heating, and instability. The outcome of the studies will thus provide important implications for the M-I energy circulation. Given the frequent occurrence and strength of DAPS and their relationship to a major ionospheric conductivity change, the findings will likely be transformational for M-I-T modeling.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.