Observations of precipitation energies during different types of pulsating aurora
Pulsating aurora (PsA) is a diffuse type of aurora with different structures switching on and off with a period of a few seconds. It is often associated with energetic electron precipitation (>10 keV) resulting in the interaction between magnetospheric electrons and electromagnetic waves in the m...
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ftunivbergen:oai:bora.uib.no:11250/2756880 2023-05-15T16:04:38+02:00 Observations of precipitation energies during different types of pulsating aurora Kebede, Fasil Tesema Partamies, Noora Tyssøy, Hilde Nesse McKay, Derek 2020 application/pdf https://hdl.handle.net/11250/2756880 https://doi.org/10.5194/angeo-38-1191-2020 eng eng Copernicus urn:issn:0992-7689 https://hdl.handle.net/11250/2756880 https://doi.org/10.5194/angeo-38-1191-2020 cristin:1855591 Annales Geophysicae. 2020, 38, 1191–1202 Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2020 The Authors Annales Geophysicae 38 6 1191-1202 Journal article Peer reviewed 2020 ftunivbergen https://doi.org/10.5194/angeo-38-1191-2020 2023-03-14T17:44:36Z Pulsating aurora (PsA) is a diffuse type of aurora with different structures switching on and off with a period of a few seconds. It is often associated with energetic electron precipitation (>10 keV) resulting in the interaction between magnetospheric electrons and electromagnetic waves in the magnetosphere. Recent studies categorize pulsating aurora into three different types – amorphous pulsating aurora (APA), patchy pulsating aurora (PPA), and patchy aurora (PA) – based on the spatial extent of pulsations and structural stability. Differences in precipitation energies of electrons associated with these types of pulsating aurora have been suggested. In this study, we further examine these three types of pulsating aurora using electron density measurements from the European Incoherent Scatter (EISCAT) VHF/UHF radar experiments and Kilpisjärvi Atmospheric Imaging Receiver Array (KAIRA) cosmic noise absorption (CNA) measurements. Based on ground-based all-sky camera images over the Fennoscandian region, we identified a total of 92 PsA events in the years between 2010 and 2020 with simultaneous EISCAT experiments. Among these events, 39, 35, and 18 were APA, PPA, and PA types with a collective duration of 58, 43, and 21 h, respectively. We found that, below 100 km, electron density enhancements during PPAs and PAs are significantly higher than during APA. However, there are no appreciable electron density differences between PPA and APA above 100 km, while PA showed weaker ionization. The altitude of the maximum electron density also showed considerable differences among the three types, centered around 110, 105, and 105 km for APA, PPA, and PA, respectively. The KAIRA CNA values also showed higher values on average during PPA (0.33 dB) compared to PA (0.23 dB) and especially APA (0.17 dB). In general, this suggests that the precipitating electrons responsible for APA have a lower energy range compared to PPA and PA types. Among the three categories, the magnitude of the maximum electron density shows higher ... Article in Journal/Newspaper EISCAT Fennoscandian Kilpisjärvi University of Bergen: Bergen Open Research Archive (BORA-UiB) Kilpisjärvi ENVELOPE(20.767,20.767,69.034,69.034) Annales Geophysicae 38 6 1191 1202 |
institution |
Open Polar |
collection |
University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
description |
Pulsating aurora (PsA) is a diffuse type of aurora with different structures switching on and off with a period of a few seconds. It is often associated with energetic electron precipitation (>10 keV) resulting in the interaction between magnetospheric electrons and electromagnetic waves in the magnetosphere. Recent studies categorize pulsating aurora into three different types – amorphous pulsating aurora (APA), patchy pulsating aurora (PPA), and patchy aurora (PA) – based on the spatial extent of pulsations and structural stability. Differences in precipitation energies of electrons associated with these types of pulsating aurora have been suggested. In this study, we further examine these three types of pulsating aurora using electron density measurements from the European Incoherent Scatter (EISCAT) VHF/UHF radar experiments and Kilpisjärvi Atmospheric Imaging Receiver Array (KAIRA) cosmic noise absorption (CNA) measurements. Based on ground-based all-sky camera images over the Fennoscandian region, we identified a total of 92 PsA events in the years between 2010 and 2020 with simultaneous EISCAT experiments. Among these events, 39, 35, and 18 were APA, PPA, and PA types with a collective duration of 58, 43, and 21 h, respectively. We found that, below 100 km, electron density enhancements during PPAs and PAs are significantly higher than during APA. However, there are no appreciable electron density differences between PPA and APA above 100 km, while PA showed weaker ionization. The altitude of the maximum electron density also showed considerable differences among the three types, centered around 110, 105, and 105 km for APA, PPA, and PA, respectively. The KAIRA CNA values also showed higher values on average during PPA (0.33 dB) compared to PA (0.23 dB) and especially APA (0.17 dB). In general, this suggests that the precipitating electrons responsible for APA have a lower energy range compared to PPA and PA types. Among the three categories, the magnitude of the maximum electron density shows higher ... |
format |
Article in Journal/Newspaper |
author |
Kebede, Fasil Tesema Partamies, Noora Tyssøy, Hilde Nesse McKay, Derek |
spellingShingle |
Kebede, Fasil Tesema Partamies, Noora Tyssøy, Hilde Nesse McKay, Derek Observations of precipitation energies during different types of pulsating aurora |
author_facet |
Kebede, Fasil Tesema Partamies, Noora Tyssøy, Hilde Nesse McKay, Derek |
author_sort |
Kebede, Fasil Tesema |
title |
Observations of precipitation energies during different types of pulsating aurora |
title_short |
Observations of precipitation energies during different types of pulsating aurora |
title_full |
Observations of precipitation energies during different types of pulsating aurora |
title_fullStr |
Observations of precipitation energies during different types of pulsating aurora |
title_full_unstemmed |
Observations of precipitation energies during different types of pulsating aurora |
title_sort |
observations of precipitation energies during different types of pulsating aurora |
publisher |
Copernicus |
publishDate |
2020 |
url |
https://hdl.handle.net/11250/2756880 https://doi.org/10.5194/angeo-38-1191-2020 |
long_lat |
ENVELOPE(20.767,20.767,69.034,69.034) |
geographic |
Kilpisjärvi |
geographic_facet |
Kilpisjärvi |
genre |
EISCAT Fennoscandian Kilpisjärvi |
genre_facet |
EISCAT Fennoscandian Kilpisjärvi |
op_source |
Annales Geophysicae 38 6 1191-1202 |
op_relation |
urn:issn:0992-7689 https://hdl.handle.net/11250/2756880 https://doi.org/10.5194/angeo-38-1191-2020 cristin:1855591 Annales Geophysicae. 2020, 38, 1191–1202 |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2020 The Authors |
op_doi |
https://doi.org/10.5194/angeo-38-1191-2020 |
container_title |
Annales Geophysicae |
container_volume |
38 |
container_issue |
6 |
container_start_page |
1191 |
op_container_end_page |
1202 |
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1766400250243710976 |