Regional 3‐D Modeling and Verification of Geomagnetically Induced Currents in Sweden
Regional 3‐D Modeling and Verification of Geomagnetically Induced Currents in Sweden
复制标题
瑞典地磁感应电流的区域 3D 建模和验证
DOI：
10.1029/2018sw002084
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发表时间：
2019
期刊：
影响因子：
3.7
通讯作者：
J. O. Hall
中科院分区：
文献类型：
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作者：
L. Rosenqvist;J. O. Hall
在极端地磁活动的情况下，长导体中流动的地磁感应电流 (GIC) 可能会对电网等关键基础设施构成威胁。高纬度地区地磁活动更为明显；因此，瑞典等北欧国家可能容易受到 GIC 的影响。先前的研究已确定瑞典南部地区最容易受到极端太空天气的影响，但这些研究依赖于地面电导率的一维模型。然而，瑞典全国各地的底层地面电导率结构横向差异很大。因此，一维模型无法捕获地面对空间天气事件响应的理解。在本文中，我们利用周围海洋的 3D 地壳电导率图来模拟均匀磁场引起的地电地面响应。我们发现，由于地壳电导率低以及东西海岸海岸-陆地界面的影响的综合作用，瑞典南部暴露在更强的电场中。该模型还可用于计算瑞典电网中的 GIC，并已通过瑞典北部站点的 GIC 测量进行了验证。测量的和预测的 GIC 幅度非常一致。该模型可用于定量评估瑞典太空天气的危害。经过在其他站点的进一步验证，它可以用作瑞典电网中应对极端空间天气事件的强大预测工具。
Geomagnetically induced currents (GICs) flowing in long conductors can pose a threat to critical infrastructure such as the power grid in cases of extreme geomagnetic activity. Geomagnetic activity is more pronounced at high latitudes; thus, Nordic countries, such as Sweden, can potentially be vulnerable to GIC. Previous studies have identified the southern region of Sweden as the most vulnerable to extreme space weather, but these studies have relied on 1‐D models of the ground conductivity. Sweden, however, has large lateral variations in the underlying ground conductivity structure across the country. Thus, the understanding of the ground response to space weather events cannot be captured by 1‐D models. In this paper, we utilize a 3‐D crustal conductivity map with surrounding oceans to model the geoelectric ground response due to a uniform magnetic field. We show that southern Sweden is exposed to stronger electric fields due to a combined effect of a low crustal conductivity and the influence of the coast‐land interface from both the east and the west coast. The model can further be used to calculate GICs in the Swedish power grid and has been validated by GIC measurements from a site in northern Sweden. The measured and predicted GIC amplitudes are in excellent agreement. The model can be used to quantitatively asses the hazard from space weather in Sweden. Upon further validation at additional sites it can be used as a powerful predictive tool of the response to extreme space weather events in the Swedish power network.
DOI：
10.1002/2017sw001697
发表时间：
2017-10
期刊：
Space Weather
影响因子：
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作者：
T. Divett;M. Ingham;C. Beggan;G. Richardson;C. Rodger;A. Thomson;M. Dalzell
通讯作者：
T. Divett;M. Ingham;C. Beggan;G. Richardson;C. Rodger;A. Thomson;M. Dalzell