Geospace Phenomena: Assessing Danger and Understanding Mechanisms

太阳风与地球的相互作用，就像我们熟悉的风一样，会带来破坏性的风暴。能量可以在“亚暴”中以爆炸性的方式释放，亚暴通常以引人注目的极光为特征。这种“太空天气”发生在近地空间的湍流等离子体中。描述它的特征需要在地球和空间的许多点同时进行测量，我们的物理理解是基于对关键位置数据的仔细解释。磁层或地球周围的保护性磁壳的物理学仍然是科学界的一个重大挑战。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中。我的研究使用磁场和我们在地面上测量的其他量来提供空间天气拼图中缺失的部分。我们在加拿大的仪器使测量成为现代卫星群测量的补充。通过提高对那里发生的复杂过程的理解，我们还将在从导航到电力传输等领域实现实际应用。我独特的世界级极光观测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气体流就像微风一样，但有些粒子被加速到具有“放射性”的能量。 加拿大的理想位置允许研究极光的形成过程，包括神秘的“质子极光”。 我们的磁探测器一直延伸到魁北克，通过磁力线与南极洲有着重要和独特的联系。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确定它们的起源。再加上AMPERE卫星星座等天基测量，我们就可以确定电流，这是控制空间等离子体的一个重要因素。这些空间电流会导致地球上的磁偏差，在极端情况下会破坏我们的技术系统。我们将系统地利用磁场，包括来自南极相应地点的磁场，来确定各种活动水平的近地电流，测量两个半球的反应，并评估这种反应如何随太阳风条件而变化。我们将对那些有很好的卫星位置的风暴和亚暴进行详细的事件研究，以确定活跃时期磁层的动态。我们的长期目标是建立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研究对电网的影响在当地取得进展。一个创新的培训计划将基于学生留在我们的天文台和监督学生在其他大学的研究生课程。

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.