Vis enkel innførsel

dc.contributor.authorReistad, Jone Peter
dc.contributor.authorØstgaard, Nikolai
dc.contributor.authorTenfjord, Paul
dc.contributor.authorLaundal, Karl Magnus
dc.contributor.authorSnekvik, Kristian
dc.contributor.authorHaaland, Stein
dc.contributor.authorMilan, Steve
dc.contributor.authorOksavik, Kjellmar
dc.contributor.authorFrey, H. U.
dc.contributor.authorGrokott, A.
dc.description.abstractHere we present an event where simultaneous global imaging of the aurora from both hemispheres reveals a large longitudinal shift of the nightside aurora of about 3 h, being the largest relative shift reported on from conjugate auroral imaging. This is interpreted as evidence of closed field lines having very asymmetric footpoints associated with the persistent positive y component of the interplanetary magnetic field before and during the event. At the same time, the Super Dual Auroral Radar Network observes the ionospheric nightside convection throat region in both hemispheres. The radar data indicate faster convection toward the dayside in the dusk cell in the Southern Hemisphere compared to its conjugate region. We interpret this as a signature of a process acting to restore symmetry of the displaced closed magnetic field lines resulting in flux tubes moving faster along the banana cell than the conjugate orange cell. The event is analyzed with emphasis on Birkeland currents (BC) associated with this restoring process, as recently described by Tenfjord et al. (2015). Using data from the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) during the same conditions as the presented event, the large-scale BC pattern associated with the event is presented. It shows the expected influence of the process of restoring symmetry on BCs. We therefore suggest that these observations should be recognized as being a result of the dynamic effects of restoring footpoint symmetry on closed field lines in the nightside.en_US
dc.publisherAGU Publicationsen_US
dc.relation.ispartof<a href="" target="blank">Mechanisms responsible for asymmetric aurora between the conjugate hemispheres</a>en_US
dc.rightsAttribution CC BY 4.0eng
dc.subjectasymmetric footpointseng
dc.subjectasymmetric convectioneng
dc.subjectasymmetric field-aligned currentseng
dc.titleDynamic effects of restoring footpoint symmetry on closed magnetic field linesen_US
dc.typePeer reviewed
dc.typeJournal article
dc.rights.holderCopyright 2016 The Authorsen_US
dc.source.journalJournal of Geophysical Research: Space Physics
dc.subject.nsiVDP::Matematikk og Naturvitenskap: 400en_US

Tilhørende fil(er)


Denne innførselen finnes i følgende samling(er)

Vis enkel innførsel

Attribution CC BY 4.0
Med mindre annet er angitt, så er denne innførselen lisensiert som Attribution CC BY 4.0