CMG Collaborative Research: Spatiotemporal Multifractal Modeling and Local Prediction of Magnetic Storms

CMG 合作研究：磁暴时空多重分形建模与局地预报

• 批准号: 0852746
• 负责人: James Wanliss
• 金额: $ 3.79万
• 依托单位: Presbyterian College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-15 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0852746&HistoricalAwards=false
• 关键词: CMG; Collaborative; Research; Spatiotemporal; Multifractal

Magnetic storms result when the magnetized plasma that propagates away from the sun interacts with the near-earth space plasma environment. Such storms typically begin with a sudden worldwide increase in the magnetic field that lasts several minutes to several hours, followed by the main phase, which typically lasts about a day, and features large reductions in the magnetic field strength. The global influence of magnetic storms was recognized over eighty years ago, and the currents that they induce in earth and space-borne systems can have considerable impacts. For example, damage from the March 1989 storm was estimated in the order of billions of dollars. Given that the magnetic field can vary significantly within the continental scale, and that its rate of change causes damage, there is a need to model and predict local variability. This project will lay the mathematical foundation for a localized magnetic storm prediction system, which will allow assessment of geomagnetically induced currents and implementation of damage limitation strategies where necessary. Information on fluctuations in the magnetic field can be gleaned from ground and satellite based magnetometers. Although individual magnetometers provide a wealth of temporal information, the paucity of ground-based magnetometers limits our predictive capability of the local behavior of magnetic storms. New mathematical techniques are required. To address the above issue, we propose to solve the following geophysical problems: (i) modeling and prediction of magnetometer time series; (ii) spatiotemporal modeling of the magnetic field; (iii) spatial interpolation of the magnetic field at unobserved locations. We will concentrate our study on the available high acquisition-rate magnetometers in North America. Although these stations offer limited spatial coverage, they provide an abundance of temporal data. The methodologies employed in this project go beyond existing approaches and take into account the very high time resolution of magnetometer measurements. This will compensate for the sparsity of spatial measurements and yield information at unobserved locations. The spatiotemporal mathematical and statistical modeling techniques presented in this proposal are novel and innovative. As such, this proposal will advance the state of the art in both geosciences and mathematical sciences. Members of the project team, which is composed of geoscientists and mathematical scientists, possess the expertise to achieve these aims in a truly interdisciplinary fashion. By providing a physical framework for the spatiotemporal variability of magnetic fields, the proposed work will allow for deeper insight into the underlying physical mechanisms of magnetic storms. Many monitoring systems perform spatially sparse measurements. The proposed work, which addresses the spatial interpolation problem, will therefore find applications in diverse areas of the geosciences and broader scientific community. The most developed societies, which rely upon high technologies for daily essentials such as energy and communications, are most susceptible to the effects of magnetic storms. As society becomes increasingly dependent upon high-technology earth- and space-borne systems, the need to model and predict spatiotemporal fluctuations in the magnetosphere will become increasingly important.

当远离太阳传播的磁化等离子体与近地空间等离子体环境相互作用时，就会产生磁暴。 这种风暴通常开始时，全球磁场突然增加，持续几分钟到几个小时，然后是主阶段，通常持续一天左右，其特征是磁场强度大幅降低。 磁暴的全球影响在80多年前就被认识到，它们在地球和空间系统中引起的电流可能产生相当大的影响。 例如，1989年3月的风暴造成的损失估计为数十亿美元。 鉴于磁场在大陆范围内变化很大，其变化率会造成损害，因此有必要对局部变化进行建模和预测。 该项目将为一个局部磁暴预测系统奠定数学基础，从而能够评估地磁感应电流，并在必要时实施损害限制战略。 关于磁场波动的信息可以从地面和卫星磁强计收集。 虽然单个磁力计提供了丰富的时间信息，但地面磁力计的缺乏限制了我们对磁暴局部行为的预测能力。 需要新的数学技术。 为了解决上述问题，我们提出解决以下地球物理问题：（i）建模和预测的磁强计时间序列;（ii）时空建模的磁场;（iii）空间插值的磁场在未观测到的位置。 我们将集中我们的研究在北美现有的高采集率磁力仪。 虽然这些台站提供的空间覆盖范围有限，但它们提供了丰富的时间数据。 该项目采用的方法超出了现有的方法，并考虑到磁力计测量的非常高的时间分辨率。 这将补偿空间测量的稀疏性，并在未观察到的位置产生信息。 在这个建议中提出的时空数学和统计建模技术是新颖的和创新的。 因此，这一建议将推动地球科学和数学科学的发展。 项目小组成员由地球科学家和数学科学家组成，拥有以真正的跨学科方式实现这些目标的专业知识。 通过为磁场的时空变化提供一个物理框架，拟议的工作将允许更深入地了解磁暴的基本物理机制。 许多监测系统执行空间稀疏测量。 因此，拟议的工作将解决空间插值问题，并将在地球科学的各个领域和更广泛的科学界得到应用。 最发达的社会依赖高科技来提供能源和通信等日常必需品，因此最容易受到磁暴的影响。 随着社会越来越依赖高技术的地球和空间系统，对磁层时空波动进行建模和预测的必要性将变得越来越重要。