地磁感应电流研究综述

Review of geomagnetically induced currents

因太阳活动而引起的地磁扰动,会在地球表面感生出地电场,从而在地表附近的导体系统中产生地磁感应电流(GICs).太阳表面的异常活动而引起的磁暴会导致强烈的GICs,严重威胁电信设备、电网、油气管道和铁路运输网络等基础设施系统的安全运行,已经成为最严重的空间天气灾害之一.因此,对GICs进行深入研究以建立对其做出迅速预测的能力,在科学和应用方面都有重要意义.本文综述了GICs的研究进展,从引入空间天气的概念开始,将GICs作为从太阳活动到太阳风再到地球扰动的空间天气链的最终环节;重点阐述了GICs的计算中所涉及的三个步骤:地球表面地磁场重建、感应地电场的计算,以及地面导体系统中GICs计算;对每一步骤中主要方法的相关原理和应用做了简要介绍与评估;最后总结了当前GICs的研究现状,并对未来GICs的研究方向与挑战进行了展望.

Geomagnetic disturbances caused by solar activities induce geoelectric fields on the earth's surface,which generate geomagnetically induced currents(GICs)in electrically conducting systems.Magnetic storms caused by anomalous solar activities produce strong GICsthat posing severe threats to the security operations of telecommunication systems,electric power grids,oil and gas pipelines,railway transportation networks and other infrastructure systems,and represent one of the most serious space weather hazards.Therefore,studying GICs for the purpose of rapid GICs forecasting has both scientific as well as practical significances.In this article,we re-view the development of GICs-related research.We begin by introducing the concept of space weather chain in which GICs are the final link of the space weather chain involving the solar activity,the solar wind,and geomag-netic disturbance.Then we focus on the three steps in GICs calculation:reconstruction of the geomagnetic field,calculation of induced geoelectric field,and modeling of GICs in ground electrically-conducting systems.Major techniques as well as related theories and applications used in each step are summarized and evaluated.Finally,we also provide assessments of the current status of GICs research,and outlook of its future directions and major chal-lenges.