Comprehensive Study of 3D Magnetosphere-Ionospheric Current System Through the Modeling, Observations, and Applications: Auroral Electrojet Indices for the Southern Hemisphere

地球三维磁层-电离层电流系统是地球空间环境的重要组成部分。这些电流是由太阳风（来自太阳的永久等离子体流）与地球磁层的相互作用驱动的，通过地磁场对齐的电流将大量的能量和动量转移到高纬度电离层和高层大气。三维电流系统动态影响北方和南极地区，通过地球电离层中这些电流的闭合引起它们的动态变化和加热。这些电流可以被模拟，但它们很难从地面甚至从太空观察到-只有它们对地磁场变化（以及地磁活动的相应指数）的影响可以通过适当放置的地面仪器记录下来。该奖项将支持通过模型开发和模拟结果与地面和卫星观测结果的比较，对半球间场向电流这一相对未被探索的现象进行研究。这一新模型将大大增进我们对两个半球空间天气驱动过程物理学的理解，并大大增进描述南极地区地磁活动的指数的制定。后者很重要，因为使用现有的耳电射流（AE）技术（使用北方极光区12个地磁观测站的数据）计算该指数不适用于南大洋上空约50%的全球覆盖范围的南极极光区。只有5-6个南极沿海研究站可以为该指数计算做出贡献，这远低于传统AE计算技术的最佳值。这项研究工作有可能显着提高我们的理解所发挥的作用，半球电流的动力学的极地和极光regions.This奖项反映了NSF的法定使命，并已被认为是值得的支持，通过评估使用基金会的智力价值和更广泛的影响审查标准。

The Earth's three-dimensional magnetosphere-ionosphere current system is an important component of the Geospace environment. These currents are driven by the interaction of solar wind (an everlasting plasma flow from the Sun) with the Earth's magnetosphere, transferring significant amounts of energy and momentum into the high-latitude ionosphere and upper atmosphere via the geomagnetic field-aligned currents. The 3D current system dynamics affect both the Northern and South Polar Regions, causing their dynamic changes and heating through the closure of these currents in the Earth's ionosphere. These currents can be modeled, but they are difficult to observe from the ground or even from space - only their effects on geomagnetic field variations (and respective indices of geomagnetic activity) can be recorded by properly placed ground-based instruments. This award will support a study of a relatively unexplored phenomenon of interhemispheric field-aligned currents through the model development and comparison of modeled results with the ground-based and satellites observations. This new model will significantly advance our understanding of the physics of space weather-driving processes in both hemispheres and development of an index describing geomagnetic activities in the Southern polar region. The latter is important because calculating this index using existing Aural Electrojet (AE) technique (that uses data from 12 geomagnetic observatories across the Northern auroral region) is not applicable to the Southern auroral region that goes over Southern Ocean for ~50% of the global coverage. There are only 5-6 Antarctic costal research stations that can contribute to this index calculations, which is much less than optimal for the traditional AE calculation technique. This research effort has the potential to significantly increase our understanding of the role played by interhemispheric currents on the dynamics of the polar and auroral regions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.