Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (B-y similar or equal to vertical bar B-z vertical bar) IMF orientation
In a case study we demonstrate the spatiotemporal structure of aurora and plasma convection in the cusp/polar cap when the interplanetary magnetic field (IMF) Bz < 0 and By ~ | Bz | (clock angle in GSM Y - Z plane: ~ 135°). This IMF orientation elicited a response different from that correspondin...
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2003
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Online Access: | https://figshare.com/articles/journal_contribution/Multi-site_observations_of_the_association_between_aurora_and_plasma_convection_in_the_cusp_polar_cap_during_a_southeastward_B-y_similar_or_equal_to_vertical_bar_B-z_vertical_bar_IMF_orientation/10130924 |
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ftleicesterunfig:oai:figshare.com:article/10130924 2023-05-15T15:19:01+02:00 Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (B-y similar or equal to vertical bar B-z vertical bar) IMF orientation P. E. Sandholt J. Moen C. J. Farrugia S. W. H. Cowley M. Lester S. E. Milan C. Valladares W. F. Denig S. Eriksson 2003-02-28T00:00:00Z https://figshare.com/articles/journal_contribution/Multi-site_observations_of_the_association_between_aurora_and_plasma_convection_in_the_cusp_polar_cap_during_a_southeastward_B-y_similar_or_equal_to_vertical_bar_B-z_vertical_bar_IMF_orientation/10130924 unknown 2381/39440 https://figshare.com/articles/journal_contribution/Multi-site_observations_of_the_association_between_aurora_and_plasma_convection_in_the_cusp_polar_cap_during_a_southeastward_B-y_similar_or_equal_to_vertical_bar_B-z_vertical_bar_IMF_orientation/10130924 All Rights Reserved Uncategorized Science & Technology Physical Sciences Astronomy & Astrophysics Geosciences Multidisciplinary Meteorology & Atmospheric Sciences Geology magnetospheric physics auroral phenomena magnetopause cusp and boundary layers plasma convection INTERPLANETARY MAGNETIC-FIELD FLUX-TRANSFER EVENTS MAGNETOSPHERE-IONOSPHERE SYSTEM HIGH-LATITUDE CONVECTION DAYSIDE MAGNETOPAUSE ALIGNED CURRENTS HF RADAR CUSP AURORA POLAR CUSP RECONNECTION Text Journal contribution 2003 ftleicesterunfig 2021-11-11T19:36:22Z In a case study we demonstrate the spatiotemporal structure of aurora and plasma convection in the cusp/polar cap when the interplanetary magnetic field (IMF) Bz < 0 and By ~ | Bz | (clock angle in GSM Y - Z plane: ~ 135°). This IMF orientation elicited a response different from that corresponding to strongly northward and southward IMF. Our study of this "intermediate state" is based on a combination of ground observations of optical auroral emissions and ionospheric plasma convection. Utilizing all-sky cameras at NyAlesund, Svalbard and Heiss Island (Russian arctic), we are able to monitor the high-latitude auroral activity within the ~10:00–15:00 MLT sector. Information on plasma convection is obtained from the SuperDARN radars, with emphasis placed on line of sight observations from the radar situated in Hankasalmi, Finland (Cutlass). A central feature of the auroral observations in the cusp/polar cap region is a ~ 30-min long sequence of four brightening events, some of which consists of latitudinally and longitudinally separated forms, which are found to be associated with pulsed ionospheric flows in merging and lobe convection cells. The auroral/convection events may be separated into different forms/cells and phases, reflecting a spatiotem-poral evolution of the reconnection process on the dayside magnetopause. The initial phase consists of a brightening in the postnoon sector (~ 12:00–14:00 MLT) at ~ 73° MLAT, accompanied by a pulse of enhanced westward convection in the postnoon merging cell. Thereafter, the event evolution comprises two phenomena which occur almost simultaneously: (1) westward expansion of the auroral brightening (equatorward boundary intensification) across noon, into the ~ 10:00–12:00 MLT sector, where the plasma convection subsequently turns almost due north, in the convection throat, and where classical poleward moving auroral forms (PMAFs) are observed; and (2) auroral brightening at slightly higher latitudes (~ 75° MLAT) in the postnoon lobe cell, with expansion towards noon, ... Other Non-Article Part of Journal/Newspaper Arctic Svalbard University of Leicester: Figshare Arctic Svalbard |
institution |
Open Polar |
collection |
University of Leicester: Figshare |
op_collection_id |
ftleicesterunfig |
language |
unknown |
topic |
Uncategorized Science & Technology Physical Sciences Astronomy & Astrophysics Geosciences Multidisciplinary Meteorology & Atmospheric Sciences Geology magnetospheric physics auroral phenomena magnetopause cusp and boundary layers plasma convection INTERPLANETARY MAGNETIC-FIELD FLUX-TRANSFER EVENTS MAGNETOSPHERE-IONOSPHERE SYSTEM HIGH-LATITUDE CONVECTION DAYSIDE MAGNETOPAUSE ALIGNED CURRENTS HF RADAR CUSP AURORA POLAR CUSP RECONNECTION |
spellingShingle |
Uncategorized Science & Technology Physical Sciences Astronomy & Astrophysics Geosciences Multidisciplinary Meteorology & Atmospheric Sciences Geology magnetospheric physics auroral phenomena magnetopause cusp and boundary layers plasma convection INTERPLANETARY MAGNETIC-FIELD FLUX-TRANSFER EVENTS MAGNETOSPHERE-IONOSPHERE SYSTEM HIGH-LATITUDE CONVECTION DAYSIDE MAGNETOPAUSE ALIGNED CURRENTS HF RADAR CUSP AURORA POLAR CUSP RECONNECTION P. E. Sandholt J. Moen C. J. Farrugia S. W. H. Cowley M. Lester S. E. Milan C. Valladares W. F. Denig S. Eriksson Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (B-y similar or equal to vertical bar B-z vertical bar) IMF orientation |
topic_facet |
Uncategorized Science & Technology Physical Sciences Astronomy & Astrophysics Geosciences Multidisciplinary Meteorology & Atmospheric Sciences Geology magnetospheric physics auroral phenomena magnetopause cusp and boundary layers plasma convection INTERPLANETARY MAGNETIC-FIELD FLUX-TRANSFER EVENTS MAGNETOSPHERE-IONOSPHERE SYSTEM HIGH-LATITUDE CONVECTION DAYSIDE MAGNETOPAUSE ALIGNED CURRENTS HF RADAR CUSP AURORA POLAR CUSP RECONNECTION |
description |
In a case study we demonstrate the spatiotemporal structure of aurora and plasma convection in the cusp/polar cap when the interplanetary magnetic field (IMF) Bz < 0 and By ~ | Bz | (clock angle in GSM Y - Z plane: ~ 135°). This IMF orientation elicited a response different from that corresponding to strongly northward and southward IMF. Our study of this "intermediate state" is based on a combination of ground observations of optical auroral emissions and ionospheric plasma convection. Utilizing all-sky cameras at NyAlesund, Svalbard and Heiss Island (Russian arctic), we are able to monitor the high-latitude auroral activity within the ~10:00–15:00 MLT sector. Information on plasma convection is obtained from the SuperDARN radars, with emphasis placed on line of sight observations from the radar situated in Hankasalmi, Finland (Cutlass). A central feature of the auroral observations in the cusp/polar cap region is a ~ 30-min long sequence of four brightening events, some of which consists of latitudinally and longitudinally separated forms, which are found to be associated with pulsed ionospheric flows in merging and lobe convection cells. The auroral/convection events may be separated into different forms/cells and phases, reflecting a spatiotem-poral evolution of the reconnection process on the dayside magnetopause. The initial phase consists of a brightening in the postnoon sector (~ 12:00–14:00 MLT) at ~ 73° MLAT, accompanied by a pulse of enhanced westward convection in the postnoon merging cell. Thereafter, the event evolution comprises two phenomena which occur almost simultaneously: (1) westward expansion of the auroral brightening (equatorward boundary intensification) across noon, into the ~ 10:00–12:00 MLT sector, where the plasma convection subsequently turns almost due north, in the convection throat, and where classical poleward moving auroral forms (PMAFs) are observed; and (2) auroral brightening at slightly higher latitudes (~ 75° MLAT) in the postnoon lobe cell, with expansion towards noon, ... |
format |
Other Non-Article Part of Journal/Newspaper |
author |
P. E. Sandholt J. Moen C. J. Farrugia S. W. H. Cowley M. Lester S. E. Milan C. Valladares W. F. Denig S. Eriksson |
author_facet |
P. E. Sandholt J. Moen C. J. Farrugia S. W. H. Cowley M. Lester S. E. Milan C. Valladares W. F. Denig S. Eriksson |
author_sort |
P. E. Sandholt |
title |
Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (B-y similar or equal to vertical bar B-z vertical bar) IMF orientation |
title_short |
Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (B-y similar or equal to vertical bar B-z vertical bar) IMF orientation |
title_full |
Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (B-y similar or equal to vertical bar B-z vertical bar) IMF orientation |
title_fullStr |
Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (B-y similar or equal to vertical bar B-z vertical bar) IMF orientation |
title_full_unstemmed |
Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (B-y similar or equal to vertical bar B-z vertical bar) IMF orientation |
title_sort |
multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (b-y similar or equal to vertical bar b-z vertical bar) imf orientation |
publishDate |
2003 |
url |
https://figshare.com/articles/journal_contribution/Multi-site_observations_of_the_association_between_aurora_and_plasma_convection_in_the_cusp_polar_cap_during_a_southeastward_B-y_similar_or_equal_to_vertical_bar_B-z_vertical_bar_IMF_orientation/10130924 |
geographic |
Arctic Svalbard |
geographic_facet |
Arctic Svalbard |
genre |
Arctic Svalbard |
genre_facet |
Arctic Svalbard |
op_relation |
2381/39440 https://figshare.com/articles/journal_contribution/Multi-site_observations_of_the_association_between_aurora_and_plasma_convection_in_the_cusp_polar_cap_during_a_southeastward_B-y_similar_or_equal_to_vertical_bar_B-z_vertical_bar_IMF_orientation/10130924 |
op_rights |
All Rights Reserved |
_version_ |
1766349204768161792 |