Interhemispheric Comparisons of Large Nighttime Magnetic Perturbation Events Relevant to GICs
Interhemispheric Comparisons of Large Nighttime Magnetic Perturbation Events Relevant to GICs
复制标题
与 GIC 相关的大型夜间磁扰动事件的半球间比较
DOI:
10.1029/2020ja028128
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发表时间:
2020
期刊:
影响因子:
--
通讯作者:
Opgenoorth, Hermann
中科院分区:
文献类型:
--
作者:
Engebretson, Mark J.;Kirkevold, Kathryn R.;Steinmetz, Erik S.;Pilipenko, Viacheslav A.;Moldwin, Mark B.;McCuen, Brett A.;Clauer, C. R.;Hartinger, Michael D.;Coyle, Shane;Opgenoorth, Hermann
Nearly all studies of impulsive magnetic perturbation events (MPEs) with large magnetic field variability (dB/dt) that can produce dangerous geomagnetically induced currents (GICs) have used data from the Northern Hemisphere. Here we present details of four large‐amplitude MPE events (|ΔBx| > 900 nT and |dB/dt| > 10 nT/s in at least one component) observed between 2015 and 2018 in conjugate high‐latitude regions (65–80° corrected geomagnetic latitude), using magnetometer data from (1) Pangnirtung and Iqaluit in eastern Arctic Canada and the magnetically conjugate South Pole Station in Antarctica and (2) the Greenland West Coast Chain and two magnetically conjugate chains in Antarctica, AAL‐PIP and BAS LPM. From one to three different isolated MPEs localized in corrected geomagnetic latitude were observed during three premidnight events; many were simultaneous within 3 min in both hemispheres. Their conjugate latitudinal amplitude profiles, however, matched qualitatively at best. During an extended postmidnight interval, which we associate with an interval of omega bands, multiple highly localized MPEs occurred independently in time at each station in both hemispheres. These nighttime MPEs occurred under a wide range of geomagnetic conditions, but common to each was a negative interplanetary magnetic fieldBzthat exhibited at least a modest increase at or near the time of the event. A comparison of perturbation amplitudes to modeled ionospheric conductances in conjugate hemispheres clearly favored a current generator model over a voltage generator model for three of the four events; neither model provided a good fit for the premidnight event that occurred near vernal equinox.
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DOI:
10.1029/2019ja026794
发表时间:
2019-09
期刊:
Journal of Geophysical Research: Space Physics
影响因子:
--
作者:
Mark J. Engebretson;V. Pilipenko;L. Ahmed;J. Posch;E. Steinmetz;M. Moldwin;Martin G. Connors
通讯作者:
Mark J. Engebretson;V. Pilipenko;L. Ahmed;J. Posch;E. Steinmetz;M. Moldwin;Martin G. Connors
影响因子:
5.2
作者:
S. Apatenkov;V. Pilipenko;E. Gordeev;A. Viljanen;L. Juusola;V. Belakhovsky;Y. Sakharov;V. Selivanov
通讯作者:
V. Selivanov
DOI:
--
发表时间:
1983
期刊:
影响因子:
--
作者:
H. Opgenoorth;J. Oksman;K. Kaila;E. Nielsen;Wolfgang Baumjohann
通讯作者:
Wolfgang Baumjohann
DOI:
--
发表时间:
--
期刊:
影响因子:
--
作者:
通讯作者:
--
影响因子:
1.9
作者:
A. Viljanen;E. Tanskanen;A. Pulkkinen
通讯作者:
A. Pulkkinen