Cargando…

Dusk‐Dawn Asymmetries in SuperDARN Convection Maps

The Super Dual Auroral Radar Network (SuperDARN) is a collection of radars built to study ionospheric convection. We use a 7‐year archive of SuperDARN convection maps, processed in 3 different ways, to build a statistical understanding of dusk‐dawn asymmetries in the convection patterns. We find tha...

Descripción completa

Detalles Bibliográficos
Autores principales: Walach, M.‐T., Grocott, A., Thomas, E. G., Staples, F.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: John Wiley and Sons Inc. 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10078218/
https://www.ncbi.nlm.nih.gov/pubmed/37032659
http://dx.doi.org/10.1029/2022JA030906
_version_ 1785020470819553280
author Walach, M.‐T.
Grocott, A.
Thomas, E. G.
Staples, F.
author_facet Walach, M.‐T.
Grocott, A.
Thomas, E. G.
Staples, F.
author_sort Walach, M.‐T.
collection PubMed
description The Super Dual Auroral Radar Network (SuperDARN) is a collection of radars built to study ionospheric convection. We use a 7‐year archive of SuperDARN convection maps, processed in 3 different ways, to build a statistical understanding of dusk‐dawn asymmetries in the convection patterns. We find that the data set processing alone can introduce a bias which manifests itself in dusk‐dawn asymmetries. We find that the solar wind clock angle affects the balance in the strength of the convection cells. We further find that the location of the positive potential foci is most likely observed at latitudes of 78° for long periods (>300 min) of southward interplanetary magnetic field (IMF), as opposed to 74° for short periods (<20 min) of steady IMF. For long steady dawnward IMF the median is also at 78°. For long steady periods of duskward IMF, the positive potential foci tends to be at lower latitudes than the negative potential and vice versa during dawnward IMF. For long periods of steady Northward IMF, the positive and negative cells can swap sides in the convection pattern. We find that they move from ∼0–9 MLT to 15 MLT or ∼15–23 MLT to 10 MLT, which reduces asymmetry in the average convection cell locations for Northward IMF. We also investigate the width of the region in which the convection returns to the dayside, the return flow width. Asymmetries in this are not obvious, until we select by solar wind conditions, when the return flow region is widest for the negative convection cell during Southward IMF.
format Online
Article
Text
id pubmed-10078218
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher John Wiley and Sons Inc.
record_format MEDLINE/PubMed
spelling pubmed-100782182023-04-07 Dusk‐Dawn Asymmetries in SuperDARN Convection Maps Walach, M.‐T. Grocott, A. Thomas, E. G. Staples, F. J Geophys Res Space Phys Research Article The Super Dual Auroral Radar Network (SuperDARN) is a collection of radars built to study ionospheric convection. We use a 7‐year archive of SuperDARN convection maps, processed in 3 different ways, to build a statistical understanding of dusk‐dawn asymmetries in the convection patterns. We find that the data set processing alone can introduce a bias which manifests itself in dusk‐dawn asymmetries. We find that the solar wind clock angle affects the balance in the strength of the convection cells. We further find that the location of the positive potential foci is most likely observed at latitudes of 78° for long periods (>300 min) of southward interplanetary magnetic field (IMF), as opposed to 74° for short periods (<20 min) of steady IMF. For long steady dawnward IMF the median is also at 78°. For long steady periods of duskward IMF, the positive potential foci tends to be at lower latitudes than the negative potential and vice versa during dawnward IMF. For long periods of steady Northward IMF, the positive and negative cells can swap sides in the convection pattern. We find that they move from ∼0–9 MLT to 15 MLT or ∼15–23 MLT to 10 MLT, which reduces asymmetry in the average convection cell locations for Northward IMF. We also investigate the width of the region in which the convection returns to the dayside, the return flow width. Asymmetries in this are not obvious, until we select by solar wind conditions, when the return flow region is widest for the negative convection cell during Southward IMF. John Wiley and Sons Inc. 2022-12-20 2022-12 /pmc/articles/PMC10078218/ /pubmed/37032659 http://dx.doi.org/10.1029/2022JA030906 Text en ©2022. The Authors. https://creativecommons.org/licenses/by/4.0/This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research Article
Walach, M.‐T.
Grocott, A.
Thomas, E. G.
Staples, F.
Dusk‐Dawn Asymmetries in SuperDARN Convection Maps
title Dusk‐Dawn Asymmetries in SuperDARN Convection Maps
title_full Dusk‐Dawn Asymmetries in SuperDARN Convection Maps
title_fullStr Dusk‐Dawn Asymmetries in SuperDARN Convection Maps
title_full_unstemmed Dusk‐Dawn Asymmetries in SuperDARN Convection Maps
title_short Dusk‐Dawn Asymmetries in SuperDARN Convection Maps
title_sort dusk‐dawn asymmetries in superdarn convection maps
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10078218/
https://www.ncbi.nlm.nih.gov/pubmed/37032659
http://dx.doi.org/10.1029/2022JA030906
work_keys_str_mv AT walachmt duskdawnasymmetriesinsuperdarnconvectionmaps
AT grocotta duskdawnasymmetriesinsuperdarnconvectionmaps
AT thomaseg duskdawnasymmetriesinsuperdarnconvectionmaps
AT staplesf duskdawnasymmetriesinsuperdarnconvectionmaps