Solar Wind and Illumination Control of Plasma Irregularity Production in the Polar Cap

该项目旨在加强我们对电离层不规则性的了解，其基础是最近在南半球高纬度地区开展的工作，这些工作证明了行星际磁场与极光E区不规则性产生之间的明确联系。需要解决的根本问题是，通过间接的IMF效应与太阳诱导的电离的直接效应，太阳能控制不规则的产生。这项研究将重点评估货币基金组织对小规模违规行为的控制程度及其与其他规模的关系。该项目将解决极地斑块的存在是否是产生不规则性的必要条件，以及太阳能照明是否抑制或增强不规则性产生的问题。将调查半球间的差异，以确定太阳风驱动因素与太阳电离的相对重要性。早期对小尺度等离子体不规则的研究分析了使用火箭和/或无线电技术的当地观测结果。该项目将在其全球驱动因素的背景下分析极冠的不规则生产，重点是来自位于南极洲麦克默多的第一台美国南极高频(SuperDARN)雷达和补充仪器的观测。极冠电离层与太阳风直接相连；因此，可以预期基金组织对小规模不规则产生的影响将比先前研究的极光区域更加明显。极冠在至日附近也有合理均匀的太阳电离条件，季节之间的对比强烈，因此可以更清楚地揭示太阳的照明效果。此外，极地冰盖似乎特别多的不规则性。该项目将利用NSF资助的南极设施的数据，为美国一名新成立的教员研究员提供必要的支持，并扩大阿拉斯加地球科学领域的研究生培训计划。

This project seeks to improve our understanding of ionospheric irregularities, building on recent work at high southern latitudes that demonstrated a clear connection between the interplanetary magnetic field (IMF) and irregularity production in the auroral E-region. The fundamental issue to be addressed is solar control of irregularity production via indirect IMF effects versus direct effects of solar-induced ionization. This study will focus on evaluating the extent of IMF control of small-scale irregularities and the relationship to other scales. The project will address the question of whether the presence of the polar patches is a necessary condition for irregularity production, and whether solar illumination suppresses or enhances irregularity generation. Inter-hemispheric differences will be investigated to determine the relative importance of solar wind drivers versus solar ionization.Earlier studies of small-scale plasma irregularities have analyzed local observations using rockets and/or radio techniques. This project will analyze irregularity production in the polar cap in context of its global drivers focusing on observations from the first US Antarctic HF (SuperDARN) radar at McMurdo, Antarctica and complementary instrumentation. The polar cap ionosphere is directly connected to the solar wind; hence, one can expect IMF effects on small-scale irregularity production to be even more pronounced than in the previously studied auroral region. The polar cap also has reasonably uniform solar ionization conditions near solstices and sharp contrasts between seasons, so solar illumination effects can be revealed more clearly. In addition, the polar cap appears to be especially rich in irregularities. This project will leverage data from the NSF-funded Antarctic facilities, providing essential support for a newly-established faculty researcher in the US, and expand a graduate student training program in the geosciences area in Alaska.