Geospace Phenomena: Assessing Danger and Understanding Mechanisms

太阳风与地球的相互作用可能会带来破坏性的风暴，就像我们熟悉的风一样。能量可以在“亚风暴”中以爆炸性的方式释放，通常以戏剧性的极光为特色。这种“太空天气”发生在近地空间的湍流等离子体中。表征它需要在地球和太空中的许多点同时进行测量，而我们对物理的理解是基于对来自关键位置的数据的仔细解释。磁层的物理学，或地球周围的保护性磁壳层，仍然是科学中的一个重大挑战。我们必须推断物质和能量如何在地球附近移动，通常是从最少的数据。我的研究使用磁场和其他我们在地面上测量的量来补充太空天气谜题中缺失的部分。我们在加拿大的仪器使测量结果与现代卫星机队的测量结果相辅相成。通过提高我们对那里发生的复杂过程的理解，我们还将使从导航到电力传输等领域的实际应用成为可能。 我唯一的世界级极光天文台位于极光带和辐射带之间的过渡区域下方。磁层中的一些等离子体气体流动就像微风，但一些粒子被加速到使它们具有“放射性”的能量。加拿大的理想地理位置使得研究极光的形成过程成为可能，包括神秘的“质子极光”。我们有一直延伸到魁北克的磁性探测器，通过磁力线与南极洲建立了重要而独特的联系。除了简单地测量整个磁层和电离层的磁场外，我们还开发了强大的技术来精确定位它们的来源。加上安培卫星星座等天基测量，我们就可以确定电流，这是空间等离子体控制中的一个重要元素。这些空间电流在地球上造成磁偏差，在极端情况下可能会破坏我们的技术系统。 我们将系统地使用磁场，包括来自南极相应地点的磁场，来确定许多活动水平上的近地电流，测量两个半球的响应，并评估这种响应如何随着太阳风条件的变化而变化。我们将对那些有很好的卫星放置的风暴和亚风暴进行详细的事件研究，以确定活跃时期的磁层动力学。我们的长期目标是基于地面磁场的空间天气预测能力。 我们工作的实际方面将通过对电网影响的研究在当地进行。一项创新的培训计划将基于学生在我们天文台的停留和对其他大学研究生课程学生的监督。

The solar wind's interaction with Earth can, like the familiar wind, bring on damaging storms. Energy can be released in an explosive way in “substorms”, which often feature dramatic auroras. This “space weather” takes place in the turbulent plasmas of near-Earth space. Characterizing it requires simultaneous measurements at many points on Earth and in space, and our physical understanding is based on careful interpretation of data from critical locations. The physics of the magnetosphere, or protective magnetic shell around the Earth, remains a major challenge in science. We must infer how matter and energy move near Earth, often from a minimum of data. My research uses magnetic fields and other quantities we measure on the ground to supply missing pieces of the space weather puzzle. Our instruments in Canada make measurements complementary to those from modern fleets of satellites. By improving our understanding of the complex processes that take place there, we will also enable practical applications in areas ranging from navigation to power transmission. My unique world-class auroral observatory is located below the transition region between the auroral zone and the radiation belts. Some flows of plasma gas in the magnetosphere are like gentle breezes, but some particles are accelerated to energies that make them “radioactive”. Canada's ideal location allows investigating the processes that make auroras, including the mysterious “proton auroras”. We have magnetic detectors that stretch as far as Québec, with important and unique links to Antarctica through magnetic field lines. Beyond simply measuring magnetic fields from the whole magnetosphere and ionosphere, we have developed powerful techniques for pinpointing their origins. Adding in space-based measurements such as those of the AMPERE satellite constellation, we can determine electric currents, an important element in the control of space plasma. These space electric currents cause magnetic deviations on Earth that in extreme cases can damage our technological systems. We will systematically use magnetic fields, including those from corresponding Antarctic sites, to determine near-Earth currents at many levels of activity, measuring the response in both hemispheres and evaluating how this varies with solar wind conditions. We will perform detailed event studies of those storms and substorms for which there is excellent satellite placement, to determine the dynamics of the magnetosphere in active times. Our long-term goal is a space weather predictive ability based on ground magnetic fields. The practical aspect of our work will go forward locally through studies of effects on power grids. An innovative training program will be based on student stays at our observatory and supervision of students in graduate programs at other universities.