A study of physical mechanisms involved in the coupling between the ionosphere, the magnetosphere, and the thermosphere: an ionospheric perspective

电离层、磁层和热层之间耦合的物理机制研究：电离层视角

• 批准号: 1774-2007
• 负责人: StMaurice, JeanPierre
• 金额: $ 6.27万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=364975
• 关键词: study; physical; mechanisms; involved; coupling

The ionosphere and the neutral atmosphere in  the 100 to 500 km altitude range are both strongly affected by processes that start near the surface of the sun and give rise to the solar wind. The magnetosphere receives  energy and momentum from the solar wind. A large part of this energy and momentum is imparted to the ionosphere, which in turn transfers it to the neutral atmosphere. The primary focus of this research project is to study just how the coupling to the ionosphere and neutral atmosphere is unfolding. This means in part the study of turbulent processes, which are observed on scales ranging from cm to thousands of km. In this respect, we devote a substantial part of our research to scales a few m in size, which are particularly interesting because they  are easily detected by radars, revealing in the process many details about larger scale circulation  as well as at times pointing to violent local processes. Along these lines, we study how the ionosphere reacts to powerful radio wave heaters. In a separate kind of study we also investigate how sometimes large local electric fields and currents form in the ionosphere in response to magnetospheric perturbations. We explore the link between these ionospheric generated processes and ion outflows from the ionosphere to the magnetosphere, and we also study how the neutral atmosphere reacts to the local electrical currents that take place in these regions.  Finally, we take a more global view still of the system and study how the plasma circulation imparted by the solar wind is related to auroral activity, be it through magnetic substorms or other kinds of events. This part of our study extends to events when plasma from lower latitudes is sometimes injected to polar cap latitudes.

100至500公里高度范围内的电离层和中性大气层都受到太阳表面附近开始并引起太阳风的过程的强烈影响。磁层从太阳风中接收能量和动量。这种能量和动量的很大一部分被传递到电离层，电离层又将其转移到中性大气层。该研究项目的主要重点是研究电离层和中性大气的耦合是如何展开的。这部分意味着对湍流过程的研究，从厘米到数千公里的尺度上观察。在这方面，我们把我们的研究的很大一部分投入到几米大小的尺度上，这是特别有趣的，因为它们很容易被雷达探测到，在这个过程中揭示了许多关于大尺度环流的细节，有时也指向剧烈的局部过程。沿着这些路线，我们研究电离层如何对强大的无线电波加热器作出反应。在一个单独的研究中，我们还调查了如何有时在电离层中形成大的局部电场和电流，以响应磁层扰动。我们探索了这些电离层产生的过程和离子从电离层流出到磁层之间的联系，我们还研究了中性大气对这些区域发生的局部电流的反应。最后，我们从更全球的角度来研究系统，并研究太阳风赋予的等离子体循环如何与极光活动有关，无论是通过磁亚暴还是其他类型的事件。我们研究的这一部分扩展到了来自低纬度的等离子体有时注入极帽纬度的事件。