Modeling extreme “Carrington‐type” space weather events using three‐dimensional global MHD simulations
Modeling extreme “Carrington‐type” space weather events using three‐dimensional global MHD simulations
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使用三维全球 MHD 模拟对极端“卡林顿型”空间天气事件进行建模
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
A. Glocer
中科院分区：
文献类型：
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作者：
C. Ngwira;A. Pulkkinen;M. Kuznetsova;A. Glocer
人们越来越关注空间天气对人造技术基础设施的不利影响可能产生的严重社会后果。在过去的二十年里，在空间天气事件的第一性原理模拟方面取得了重大进展，三维(3-D)全球磁流体力学(MHD)模式一直处于这一转变的前沿，因此在促进我们对空间天气的理解方面发挥了关键作用。然而，即使对于现代的全球MHD模型来说，极端空间天气事件的模拟仍然是一个重大挑战。在这项研究中，我们介绍了一个特别适应的密歇根大学全球MHD模式，用于模拟极端空间天气事件，其DST足迹与1859年9月的卡灵顿超级风暴相当，基于Tsurutani et的估计。艾尔(2003)。给出了用“非常极端”构造的/理想化的太阳风边界条件驱动磁层的模拟运行结果。特别是，我们描述了磁层-电离层系统和地面上相关的感应地电场对这种极端驱动条件的反应。使用2003年10月观测到的万圣节风暴空间天气事件的输入数据进一步测试了模型设置，以验证MHD模型的一致性，并为今后的工作得出进一步的指导意见。这种极端空间天气MHD模型装置是专门为实际应用而设计的，用于模拟极端地磁感应电场，这种电场可以在输电网等地面导体系统中驱动大电流。因此，我们的最终目标是探索假设的风暴所能引起的地电场水平，即DST∼=−1600NT。
There is a growing concern over possible severe societal consequences related to adverse space weather impacts on man‐made technological infrastructure. In the last two decades, significant progress has been made toward the first‐principles modeling of space weather events, and three‐dimensional (3‐D) global magnetohydrodynamics (MHD) models have been at the forefront of this transition, thereby playing a critical role in advancing our understanding of space weather. However, the modeling of extreme space weather events is still a major challenge even for the modern global MHD models. In this study, we introduce a specially adapted University of Michigan 3‐D global MHD model for simulating extreme space weather events with a Dst footprint comparable to the Carrington superstorm of September 1859 based on the estimate by Tsurutani et. al. (2003). Results are presented for a simulation run with “very extreme” constructed/idealized solar wind boundary conditions driving the magnetosphere. In particular, we describe the reaction of the magnetosphere‐ionosphere system and the associated induced geoelectric field on the ground to such extreme driving conditions. The model setup is further tested using input data for an observed space weather event of Halloween storm October 2003 to verify the MHD model consistence and to draw additional guidance for future work. This extreme space weather MHD model setup is designed specifically for practical application to the modeling of extreme geomagnetically induced electric fields, which can drive large currents in ground‐based conductor systems such as power transmission grids. Therefore, our ultimate goal is to explore the level of geoelectric fields that can be induced from an assumed storm of the reported magnitude, i.e., Dst∼=−1600 nT.