Solar Wind and Interplanetary Magnetic Field Influences on the Earth's Space Environment: Solar Wind-Magnetosphere-Ionosphere Coupling

太阳风和行星际磁场对地球空间环境的影响：太阳风-磁层-电离层耦合

• 批准号: 288316-2012
• 负责人: McWilliams, Kathryn
• 金额: $ 2.33万
• 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: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=594831
• 关键词: Solar; Wind; Interplanetary; Magnetic; Field

The majority of the energy budget of the Earth's space environment is controlled by the energy transfer between the solar wind and the magnetosphere. The degree to which the highly variable solar wind couples to the magnetosphere controls the access of solar wind particles precipitating along the Earth's magnetic field lines to the upper atmosphere. Since all points in the magnetosphere are linked to the ionosphere by the geomagnetic field lines, the ionosphere acts as a large screen onto which magnetosphere dynamics are projected, allowing the ground-based instruments to remotely sense nearly the entirety of geospace. I will investigate modes of convection in the magnetosphere, which are important to understanding the response of the system to external forcing by the solar wind and interplanetary magnetic field. The magnetosphere can experience three phenomena that have, until now, been classified as physically distinct phenomena: steady magnetospheric convection, substorms, and sawtooth events. Recent work suggests that these response modes may lie more along a continuum of response. The global-scale maps of ionospheric convection that the international array of radars called SuperDARN obtains every minute are ideally suited for this work. I will also investigate the relationship between space weather and climate in the key coupling region between the two-the Earth's ionosphere. In the study of global climate, solar variability has been identified as a possible source of climate change on Earth. The mechanism remains to be identified, and next to nothing is known about how the two regions may be connected. Intriguing studies in the past have shown a correlation between the intensity of weather systems and the orientation of the interplanetary magnetic field. The ionosphere-mesosphere- thermosphere layer that lies between the electrified space environment and the neutral atmosphere holds the key to understanding how solar-terrestrial coupling may affect climate. Initial work suggests that the polar caps, where the solar wind and IMF are directly connected to the geomagnetic field, play an important role.

地球空间环境的大部分能量收支是由太阳风和磁层之间的能量转移控制的。高度变化的太阳风与磁层的耦合程度控制着太阳风粒子沿地球磁力线沉降到上层大气的途径。由于磁层中的所有点都通过地磁力线与电离层相连，电离层就像一个大屏幕，将磁层动力学投影到屏幕上，使地面仪器能够远程感知几乎整个地球空间。我将研究磁层中的对流模式，这对于理解系统对太阳风和行星际磁场的外部强迫的响应很重要。到目前为止，磁层可以经历三种物理上不同的现象：稳定磁层对流、亚暴和锯齿状事件。最近的研究表明，这些反应模式可能更多地是沿着一个连续的反应。被称为superdamn的国际雷达阵列每分钟获取的电离层对流的全球尺度地图非常适合这项工作。我还将研究空间天气和气候在两者之间的关键耦合区域-地球电离层之间的关系。在全球气候研究中，太阳变率已被确定为地球气候变化的一个可能来源。这一机制仍有待确定，而且对于这两个区域是如何连接的几乎一无所知。过去一些有趣的研究表明，天气系统的强度与行星际磁场的方向之间存在相关性。位于带电空间环境和中性大气之间的电离层-中间层-热层是理解日地耦合如何影响气候的关键。最初的研究表明，太阳风和IMF与地磁场直接相连的极帽发挥了重要作用。