摘要
基于高纬度芬兰Mantsala地区近两个太阳活动周期(1999-2017年)天然气传输管道的地磁感应电流(GIC,I_(GIC))观测数据,统计研究了GIC扰动的分布特征以及强GIC扰动与磁暴和地磁亚暴的相关性.研究发现:95.83%时间段的GIC强度分布在0~1 A之间.定义:若某个时间段|I_(GIC)|_(max)>1A,则认为发生GIC扰动;|I_(CIC)|_(max)>10 A,则认为发生强GIC扰动事件.GIC扰动在磁地方时夜侧附近发生的概率最高,这主要与地磁亚暴发生期间电离层电流最剧烈的变化发生在磁地方时夜侧附近有关;强GIC扰动经常爆发式出现,且都发生在磁暴期间,但大多数磁暴并不伴随强GIC扰动事件发生.磁暴急始驱动的强GIC扰动事件较少,由磁层压缩引起地磁场突然增强驱动的强GIC扰动事件持续时间较短;强GIC扰动事件主要发生在磁暴主相和恢复相,由环电流变化驱动的强GIC扰动事件一般持续时间较长且强度较大.
Based on the data of the Geomagnetic Induced Currents(GIC,IGIC)in the natural gas transmission pipelines in the high-latitude Mantsala area,Finland,from 1999 to 2017 during the recent two solar cycles.The distribution characteristics of GIC disturbances and the relationship between strong GIC disturbances and magnetic storms and substorms are analyzed.It is found that for 95.83%of the data points,the GIC intensity was distributed between 0 A and 1 A.The occurrence probability of GIC disturbance defined as|IGIC|_(max)>1 A,is highest near the nightside in MLT,which is possibly related to the stronger ionosphere current disturbances during the magnetospheric substorm at the nightside.All the intense GIC disturbances defined as the events with|IGIC|_(max)>10 A are accompanied by geomagnetic storms.Strong GIC disturbance events mainly occur in the main phase and the recovery phase of the magnetic storms,which are driven by ring current enhancement and have a longer time-duration and greater intensity.On the other hand,there are also a few events with a much shorter duration occurring with the storm sudden commencement.These events are caused by the sudden compression of the magnetosphere.
作者
魏佳筠
左平兵
宋小健
周梓露
WEI Jiayun;ZUO Pingbing;SONG Xiaojian;ZHOU Zilu(Institute of Space Science and Applied Technology,Harbin Institute of Technology,Shenzhen 518055)
出处
《空间科学学报》
CAS
CSCD
北大核心
2021年第4期537-545,共9页
Chinese Journal of Space Science
基金
国家自然科学基金项目(41731067,42074205)
广东省自然科学基金项目(2019A1515011067)共同资助。
关键词
GIC扰动
磁暴
地磁亚暴
Geomagnetically induced currents disturbance
Magnetic storm
Geomagnetic substorm
作者简介
魏佳筠,E-mail:20B958028@stu.hit.edu.cn。
