Space Weather: DE-1 FUV-observed Thermospheric Disturbances and Their Spatial/Temporal Correlation with Negative Ionospheric Storm Data

提出了一项为期三年的地磁风暴期间产生的热层扰动区的演变及其与负电离层风暴的相关性研究。该提案的动机是PI根据NASA的合同进行了为期两年的调查，从DE-1 FUV成像数据中获得了白天的热层成分图像。图像为O/N2的形式，在后一种中，O相对于N2的列丰度参考了固定的深度。研究表明，将辐射强度数据转换为O/N2具有足够的精度，可以有效地量化地磁暴期间高纬度地区因强烈加热而产生的O/N2减少区（O损耗斑[ODPs]）的结构和强度。根据各种风暴时间数据生成的O/N2图像显示，在扩大的中纬度地区，O/N2减少了两倍以上。在目前的工作中，重点将放在第一性原理电离层建模上，以了解在受热层扰动的中纬度地区观测到的电离层的行为。建模的一个关键方面将是在基于de -1的O/N2的约束下再现O耗尽区域内部和邻近区域的测量结果。鉴于NASA提出的工作的一个关键目标是将数据与数据（基于de的O/N2与电离层测量）相关联，这里的一个关键目标将是通过所述的建模工作更好地理解O耗尽区域内e区高度的中性密度行为。该方法试图通过修改电离层模型中使用的中性密度和风的经验模型来复制O耗竭事件期间的电离层观测。也就是说，将尝试通过从观测到的这些事件对电离层结构的影响倒推，推断出O耗竭事件中热层结构的一些情况。长期目标是能够使用O/N2的卫星图像来绘制可能经历负电离层风暴影响的区域。

A three year investigation is proposed to address the evolution of thermospherically disturbed regions produced during geomagnetic storms and their correlation with negative ionospheric storms. The proposal is motivated by the successful outcome of a two year investigation by the PI under a NASA contract to derive thermospheric composition images on the dayside from DE-1 FUV imaging data. The images are in the form of O/N2, the column abundance of O relative to N2 referenced to a fixed depth in the latter species. The work demonstrated that the radiance data can be converted to O/N2 with sufficient accuracy to effectively quantify the structure and intensity of regions of reduced O/N2 (O depletion patches [ODPs]) arising from intense heating at high latitudes during geomagnetic storms. O/N2 images have been produced from various storm-time data showing reductions in O/N2 by more than a factor of two over extended mid-latitude regions. In the current work, the focus will be on first-principles ionospheric modeling to understand the behavior of the observed ionosphere within thermospherically disturbed mid-latitude regions. A key aspect of the modeling will be to reproduce the measure-ments inside and adjacent of O depleted regions within constraints imposed by DE-1-based O/N2. Whereas a key goal of the proposed NASA work will be correlating data with data (DE-based O/N2 with ionospheric measurements), here a key goal will be to better understand the neutral density behavior at E-region heights within O depleted regions through the stated modeling effort. The approach is to attempt to replicate ionospheric observations during O depletion events by modifying the empirical models of neutral densities and winds used in the ionospheric models. That is, an attempt will be made to deduce something about thermospheric structure in O depletion events by working backwards from the observed effects of these events on ionospheric structure. The long range goal is to be able to use satellite images of O/N2 to map out regions likely to be experiencing negative ionospheric storm effects.