CEDAR: Auroral Electrojet Waves and Wave Heating

高纬度地区极光降水的一个重要影响是电离层产生波和湍流。这些动态变化可能导致通过电离层的通信和导航信号的中断和退化。尽管早在75年前就在极光区发现了电离层的不规则现象，但关于电离层在湍流状态下传播和饱和的方式的基本问题仍然存在。这个奖项的目的是研究一种被称为法利-布曼波的特殊湍流。目的是研究这些波的内部力学，它们对背景电离层状态的影响，以及可以从它们接收到的相干雷达后向散射的解释。该调查具有实验、理论和建模方面以及强大的教育基础。这项研究的总体目标是阐明通过磁层强迫（从上方）产生电离层结构的过程，这是2013年太阳和空间物理年代际调查强调的两个主题之一。它强调在扰动条件下可用的背景强迫、极光不稳定和它所产生的湍流以及对平均电离层状态的反馈之间的多尺度联系，构成了对这一复杂和高度耦合过程的系统方法。拟议的研究将由康奈尔大学和阿拉斯加大学安克雷奇分校的教师和学生进行，并将涉及阿拉斯加的实验现场工作。实验数据将在理论研究结果的背景下进行解释。该研究的一个组成部分涉及构建法利-布曼波的三维混合流体动力学模型，该模型能够在小尺度和中等尺度上模拟波动力学。第二个部分涉及基于随机微分方程（SDEs）形式的法利-布曼波和湍流（包括饱和效应）的数学模型的发展。这项调查的广泛影响与将开发的工具的新颖性有关，这些工具在雷达极光研究之外也有应用。雷达成像作为在地球空间进行发现研究的一种手段具有巨大的潜力，但它对计算的要求很高，除非能够简化和加速，否则在目前的努力之外几乎没有应用。康奈尔大学和阿拉斯加大学的地球空间和雪松科学的本科和研究生教育将产生更广泛的影响。

One of the important effects of auroral precipitation at high latitudes is the production of waves and turbulence in the ionosphere. These dynamic variations can cause disruption and degradation of communication and navigation signals that pass through the ionosphere. Although ionospheric irregularities were discovered in the auroral zone more than 75 years ago, fundamental questions about the way that the waves propagate and saturate in a turbulent state persist. The purpose of this award is to investigate a particular kind of turbulence referred to as Farley-Buneman waves. The objective is to study the internal mechanics of these waves, their effects on the background ionospheric state, and the interpretation of coherent radar backscatter that can be received from them. The investigation has experimental, theoretical, and modeling aspects as well as strong educational underpinnings. The broad goal of the research is to elucidate the processes involved in generating ionospheric structure by magnetospheric forcing (from above), one of the two main themes highlighted by the 2013 Decadal Survey for Solar and Space Physics. Its emphasis on the multiscale connections between the background forcing available during disturbed conditions, the auroral instability and turbulence it creates, and the feedback on the mean ionospheric state constitutes a systems approach to this complex and highly coupled process. The proposed study will be carried out by faculty and students at Cornell University and the University of Alaska, Anchorage, and will involve experimental field work in Alaska. Experimental data will be interpreted in the context of results from the theoretical investigation. One component of that investigation involves the construction of a 3D hybrid fluid-kinetic model of Farley- Buneman waves capable of simulating the wave mechanics at small and intermediate scales. The second component involves the development of a mathematical model of Farley-Buneman waves and turbulence, including saturation effects, based on the formalism of stochastic differential equations (SDEs). The broader impact of this investigation is associated with the novelty of the tools that will be developed, which have applications outside research in the radar aurora. Radar imaging has tremendous potential as a means of performing discovery research in geospace but is computationally demanding and will see little application outside the current effort until it can be simplified and accelerated. Additional broader impact will come from undergraduate and graduate education in geospace and CEDAR science at Cornell and the University of Alaska.