CMG: Modeling the Multiscale Phenomena of the Magnetosphere

CMG：模拟磁层的多尺度现象

• 批准号: 0417800
• 负责人: A Surjalal Sharma
• 金额: --
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-15 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0417800&HistoricalAwards=false
• 关键词: CMG; Modeling; Multiscale; Phenomena; Magnetosphere

Earth's magnetosphere, which is a cavity formed by the interaction of the turbulent solar wind with the dipole magnetic field, is a key region of geospace involving a broad range of interacting scales, a complex geometry and a rich variety of physical processes. The data from the ground and space based observatories have been used extensively to develop data-derived models of the magnetosphere. The coherence on the global scale, obtained in terms of low dimensionality of its dynamics, and the consequent predictability of its dynamics, has been instrumental in the development of initiatives for forecasting space weather. The multi-scale properties, on the other hand, can not be predicted dynamically and the methods of nonlinear dynamics and statistical physics have been combined to develop comprehensive models that yield deterministic predictions of the global features and probabilistic predictions of its multi-scale aspects. The next challenge lies in the development of the mathematical framework for these results, and requires a strong collaborative efforts between geosciences and mathematics. The multi-scale properties make the fractional kinetic equations, which combines the dynamical and statistical approaches, a natural choice as a mathematical framework for modeling the coupled solar wind - magnetosphere system. The project will develop comprehensive models of multi-scale phenomena of the magnetosphere by combining three approaches, viz., data derived modeling, theory of fractional kinetics, and global MHD simulations. The combination of these three approaches requires a close interdisciplinary collaboration of mathematicians and geoscientists, and will be undertaken by research teams at Courant Institute of Mathematical Sciences and University of Maryland. The proposed research will have broader impacts by providing a mathematical framework enabling improved forecasting of geospace disturbances. Such a framework is essential for improving the current forecasts of the hazardous events in the near-Earth space. The geospace storms and substorms have serious impacts on modern technological systems such as communication satellites, power grids, human space flight, etc. The improvement of the current capabilities for forcasting the conditions in the different regions of geospace, such as the ionosphere and the radiation belt, is of strategic importance to national security. Further, the development of mathematical framework for multiscale behavior of the geospace will stimulate the understanding of the similar features in the atmosphere, and potentially of the linkages between these two regions and how they are controlled by changes in the solar activity.

地球磁层是湍流太阳风与偶极磁场相互作用形成的空腔，是地球空间的一个关键区域，涉及广泛的相互作用尺度、复杂的几何形状和丰富多样的物理过程。来自地面和空间观测站的数据已被广泛用于开发磁层数据衍生模型。由于其动态的低维度性而获得的全球范围内的一致性以及由此产生的动态的可预测性，有助于制定空间气象预测举措。另一方面，多尺度特性不能动态预测，非线性动力学和统计物理的方法已经结合起来，开发全面的模型，产生确定性预测的全球功能和概率预测的多尺度方面。下一个挑战在于这些结果的数学框架的发展，并需要地球科学和数学之间的强有力的合作努力。分数阶动力学方程结合了动力学和统计学方法，是模拟太阳风-磁层耦合系统的数学框架。该项目将通过结合三种方法，即：数据导出的建模，分数动力学理论，和全球MHD模拟。这三种方法的结合需要数学家和地球科学家的密切跨学科合作，并将由柯朗数学科学研究所的研究小组进行， 马里兰州大学。拟议的研究将提供一个数学框架，改进对地球空间扰动的预测，从而产生更广泛的影响。这种框架对于改进目前对近地空间危险事件的预测至关重要。地球空间风暴和亚暴对通信卫星、电网、载人航天等现代技术系统具有严重影响。提高对电离层、辐射带等地球空间不同区域的预测能力，对国家安全具有重要战略意义。 此外，地球空间多尺度行为的数学框架的发展将促进对大气中类似特征的理解，以及这两个区域之间的潜在联系以及它们如何受到太阳活动变化的控制。