Statistical analysis of storm-time near-Earth current systems
Currents from the Hot Electron and Ion Drift Integrator (HEIDI) inner magnetospheric model results for all of the 90 intense storms (disturbance storm-time (Dst) minimum < −100 nT) from solar cycle 23 (1996–2005) are calculated, presented, and analyzed. We have categorized these currents into...
Main Authors: | , , |
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Format: | Article |
Language: | English |
Published: |
Copernicus Publications
2015-08-01
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Series: | Annales Geophysicae |
Online Access: | https://www.ann-geophys.net/33/965/2015/angeo-33-965-2015.pdf |
Summary: | Currents from the Hot Electron and Ion Drift Integrator (HEIDI) inner
magnetospheric model results for all of the 90 intense storms (disturbance storm-time (Dst) minimum
< −100 nT) from solar cycle 23 (1996–2005) are calculated,
presented, and analyzed. We have categorized these currents into the various
systems that exist in near-Earth space, specifically the eastward and
westward symmetric ring current, the partial ring current, the banana
current, and the tail current. The current results from each run set are
combined by a normalized superposed epoch analysis technique that scales the
timeline of each phase of each storm before summing the results. It is found
that there is a systematic ordering to the current systems, with the
asymmetric current systems peaking during storm main phase (tail current
rising first, then the banana current, followed by the partial ring current)
and the symmetric current systems peaking during the early recovery phase
(westward and eastward symmetric ring current having simultaneous maxima).
The median and mean peak amplitudes for the current systems ranged from 1 to
3 MA, depending on the setup configuration used in HEIDI, except for the
eastward symmetric ring current, for which the mean never exceeded 0.3 MA
for any HEIDI setup. The self-consistent electric field description in HEIDI
yielded larger tail and banana currents than the Volland–Stern electric
field, while the partial and symmetric ring currents had similar peak values
between the two applied electric field models. |
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ISSN: | 0992-7689 1432-0576 |