elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Impressum | Datenschutz | Kontakt | English
Schriftgröße: [-] Text [+]

Introducing the “VALOR” analysis framework for auroral field-aligned current sheets using observations from Swarm Alpha and Charlie

Pick, Leonie J. L. und Vogt, Joachim und Blagau, Adrian und Stachlys, Nele (2021) Introducing the “VALOR” analysis framework for auroral field-aligned current sheets using observations from Swarm Alpha and Charlie. In: EGU General Assembly 2021, EGU21 (1263). EGUsphere, Copernicus GmbH. European Geosciences Union General Assembly (vEGU21: Gather Online), 19.-30. April 2021, virtual. doi: 10.5194/egusphere-egu21-1263.

[img] PDF
377kB

Kurzfassung

The investigation of auroral field-aligned current (FAC) sheets is crucial in the context of space weather research since they serve as main transmitters of energy and momentum across geospace domains. Different magnetosphere-ionosphere coupling modes are reflected by the FACs’ multiscale nature with spatial scales, i.e., latitudinal extensions, ranging from below 1 km to hundreds of kilometers. The multiscale property can be addressed conveniently using ESA’s three-spacecraft mission Swarm. According to common practice a linear correlation analysis is performed on lagged and band-pass filtered scalar FAC density estimates from two nearby spacecraft. We introduce the framework VALOR (Vectorial Association of Linearly Oriented Residua) which generalizes the common approach in two ways. First, VALOR utilizes the full magnetic field vector primarily observed at both spacecraft without filtering. Second, VALOR allows to test statistical association measures other than linear correlation in dependence of both time and along-track spacecraft lag. The method is further refined by considering the current sheet’s polarization, i.e., the directional preference of the associated magnetic field perturbation, which additionally constrains the sheet’s orientation. Here, we apply VALOR to 1 Hz magnetic field observations from Swarm Alpha and Charlie and base the association measure on a vectorial version of the mean squared deviation. By means of a sample auroral oval crossing event we demonstrate that the incorporation of vectorial and polarization information helps to focus the association measure in the time-lag parameter plane leading to a smaller FAC spatial scale estimate. This result seems to hold in a statistical context including over 9000 quasi-perpendicular auroral oval crossings from 2014 to 2020. The fact that the VALOR derived FAC locations reflect the known ellipsoidal shapes of the auroral ovals speaks to the overall plausibility of the method as well as the independently supported finding that large-scale FACs (>300 km) dominate the dawn and dusk sectors while smaller scale FACs gain importance at noon and midnight. Among the various opportunities for future work are an application to 50 Hz high-resolution Swarm data as well as the investigation of the solar controlling parameters.

elib-URL des Eintrags:https://elib.dlr.de/142685/
Dokumentart:Konferenzbeitrag (Vortrag)
Titel:Introducing the “VALOR” analysis framework for auroral field-aligned current sheets using observations from Swarm Alpha and Charlie
Autoren:
AutorenInstitution oder E-Mail-AdresseAutoren-ORCID-iDORCID Put Code
Pick, Leonie J. L.leonie.pick (at) dlr.dehttps://orcid.org/0000-0002-5266-9764NICHT SPEZIFIZIERT
Vogt, JoachimJacobs University, Bremen, GermanyNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Blagau, AdrianInstitute for Space Sciences, Bucharest-Magurele, RomaniaNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Stachlys, NeleJacobs University, Bremen, GermanyNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Datum:27 April 2021
Erschienen in:EGU General Assembly 2021
Referierte Publikation:Nein
Open Access:Ja
Gold Open Access:Nein
In SCOPUS:Nein
In ISI Web of Science:Nein
Band:EGU21
DOI:10.5194/egusphere-egu21-1263
Verlag:EGUsphere, Copernicus GmbH
Status:veröffentlicht
Stichwörter:Field-aligned currents, magnetic field disturbance, Swarm spacecraft
Veranstaltungstitel:European Geosciences Union General Assembly (vEGU21: Gather Online)
Veranstaltungsort:virtual
Veranstaltungsart:internationale Konferenz
Veranstaltungsdatum:19.-30. April 2021
Veranstalter :Copernicus
HGF - Forschungsbereich:Luftfahrt, Raumfahrt und Verkehr
HGF - Programm:Raumfahrt
HGF - Programmthema:Erdbeobachtung
DLR - Schwerpunkt:Raumfahrt
DLR - Forschungsgebiet:R EO - Erdbeobachtung
DLR - Teilgebiet (Projekt, Vorhaben):R - Solar-Terrestrische Physik SO, R - Projekt Weltraumwetterforschung
Standort: Neustrelitz
Institute & Einrichtungen:Institut für Solar-Terrestrische Physik > Weltraumwettereinfluß
Hinterlegt von: Pick, Dr Leonie
Hinterlegt am:09 Jul 2021 15:44
Letzte Änderung:09 Jul 2021 15:44

Nur für Mitarbeiter des Archivs: Kontrollseite des Eintrags

Blättern
Suchen
Hilfe & Kontakt
Informationen
electronic library verwendet EPrints 3.3.12
Gestaltung Webseite und Datenbank: Copyright © Deutsches Zentrum für Luft- und Raumfahrt (DLR). Alle Rechte vorbehalten.