Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region
The field-aligned neutral oscillations in the F-region (altitudes between 165 and 275 km) were compared using data obtained simultaneously with two independent instruments: the European Incoherent Scatter (EISCAT) UHF radar and a scanning Fabry-Perot interferometer (FPI). During the night of Februar...
Published in: | Annales Geophysicae |
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00036675 2023-05-15T16:04:31+02:00 Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region Oyama, S. Nozawa, S. Buchert, S. C. Ishii, M. Watari, S. Sagawa, E. Kofman, W. Lilensten, J. Fujii, R. 2000-09 electronic https://doi.org/10.1007/s00585-000-1154-z https://noa.gwlb.de/receive/cop_mods_00036675 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00036629/angeo-18-1154-2000.pdf https://angeo.copernicus.org/articles/18/1154/2000/angeo-18-1154-2000.pdf eng eng Springer Verlag Annales Geophysicae -- http://www.bibliothek.uni-regensburg.de/ezeit/?1458425 -- https://www.ann-geophys.net/ -- https://www.ann-geophys.net/volumes.html -- http://link.springer.com/journal/585 -- 1432-0576 https://doi.org/10.1007/s00585-000-1154-z https://noa.gwlb.de/receive/cop_mods_00036675 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00036629/angeo-18-1154-2000.pdf https://angeo.copernicus.org/articles/18/1154/2000/angeo-18-1154-2000.pdf https://open-access.net/ uneingeschränkt info:eu-repo/semantics/openAccess article Verlagsveröffentlichung article Text doc-type:article 2000 ftnonlinearchiv https://doi.org/10.1007/s00585-000-1154-z 2022-02-08T22:43:53Z The field-aligned neutral oscillations in the F-region (altitudes between 165 and 275 km) were compared using data obtained simultaneously with two independent instruments: the European Incoherent Scatter (EISCAT) UHF radar and a scanning Fabry-Perot interferometer (FPI). During the night of February 8, 1997, simultaneous observations with these instruments were conducted at Tromsø, Norway. Theoretically, the field-aligned neutral wind velocity can be obtained from the field-aligned ion velocity and by diffusion and ambipolar diffusion velocities. We thus derived field-aligned neutral wind velocities from the plasma velocities in EISCAT radar data. They were compared with those observed with the FPI (λ=630.0 nm), which are assumed to be weighted height averages of the actual neutral wind. The weighting function is the normalized height dependent emission rate. We used two model weighting functions to derive the neutral wind from EISCAT data. One was that the neutral wind velocity observed with the FPI is velocity integrated over the entire emission layer and multiplied by the theoretical normalized emission rate. The other was that the neutral wind velocity observed with the FPI corresponds to the velocity only around an altitude where the emission rate has a peak. Differences between the two methods were identified, but not completely clarified. However, the neutral wind velocities from both instruments had peak-to-peak correspondences at oscillation periods of about 10–40 min, shorter than that for the momentum transfer from ions to neutrals, but longer than from neutrals to ions. The synchronizing motions in the neutral wind velocities suggest that the momentum transfer from neutrals to ions was thought to be dominant for the observed field-aligned oscillations rather than the transfer from ions to neutrals. It is concluded that during the observation, the plasma oscillations observed with the EISCAT radar at different altitudes in the F-region are thought to be due to the motion of neutrals. Key words: Ionosphere (Ionosphere–atmosphere interactions) – Meteorology and atmospheric dynamics (thermospheric dynamics; waves and tides) Article in Journal/Newspaper EISCAT Tromsø Niedersächsisches Online-Archiv NOA Norway Tromsø Annales Geophysicae 18 9 1154 1163 |
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Niedersächsisches Online-Archiv NOA |
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ftnonlinearchiv |
language |
English |
topic |
article Verlagsveröffentlichung |
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article Verlagsveröffentlichung Oyama, S. Nozawa, S. Buchert, S. C. Ishii, M. Watari, S. Sagawa, E. Kofman, W. Lilensten, J. Fujii, R. Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region |
topic_facet |
article Verlagsveröffentlichung |
description |
The field-aligned neutral oscillations in the F-region (altitudes between 165 and 275 km) were compared using data obtained simultaneously with two independent instruments: the European Incoherent Scatter (EISCAT) UHF radar and a scanning Fabry-Perot interferometer (FPI). During the night of February 8, 1997, simultaneous observations with these instruments were conducted at Tromsø, Norway. Theoretically, the field-aligned neutral wind velocity can be obtained from the field-aligned ion velocity and by diffusion and ambipolar diffusion velocities. We thus derived field-aligned neutral wind velocities from the plasma velocities in EISCAT radar data. They were compared with those observed with the FPI (λ=630.0 nm), which are assumed to be weighted height averages of the actual neutral wind. The weighting function is the normalized height dependent emission rate. We used two model weighting functions to derive the neutral wind from EISCAT data. One was that the neutral wind velocity observed with the FPI is velocity integrated over the entire emission layer and multiplied by the theoretical normalized emission rate. The other was that the neutral wind velocity observed with the FPI corresponds to the velocity only around an altitude where the emission rate has a peak. Differences between the two methods were identified, but not completely clarified. However, the neutral wind velocities from both instruments had peak-to-peak correspondences at oscillation periods of about 10–40 min, shorter than that for the momentum transfer from ions to neutrals, but longer than from neutrals to ions. The synchronizing motions in the neutral wind velocities suggest that the momentum transfer from neutrals to ions was thought to be dominant for the observed field-aligned oscillations rather than the transfer from ions to neutrals. It is concluded that during the observation, the plasma oscillations observed with the EISCAT radar at different altitudes in the F-region are thought to be due to the motion of neutrals. Key words: Ionosphere (Ionosphere–atmosphere interactions) – Meteorology and atmospheric dynamics (thermospheric dynamics; waves and tides) |
format |
Article in Journal/Newspaper |
author |
Oyama, S. Nozawa, S. Buchert, S. C. Ishii, M. Watari, S. Sagawa, E. Kofman, W. Lilensten, J. Fujii, R. |
author_facet |
Oyama, S. Nozawa, S. Buchert, S. C. Ishii, M. Watari, S. Sagawa, E. Kofman, W. Lilensten, J. Fujii, R. |
author_sort |
Oyama, S. |
title |
Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region |
title_short |
Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region |
title_full |
Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region |
title_fullStr |
Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region |
title_full_unstemmed |
Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region |
title_sort |
effects of atmospheric oscillations on the field-aligned ion motions in the polar f-region |
publisher |
Springer Verlag |
publishDate |
2000 |
url |
https://doi.org/10.1007/s00585-000-1154-z https://noa.gwlb.de/receive/cop_mods_00036675 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00036629/angeo-18-1154-2000.pdf https://angeo.copernicus.org/articles/18/1154/2000/angeo-18-1154-2000.pdf |
geographic |
Norway Tromsø |
geographic_facet |
Norway Tromsø |
genre |
EISCAT Tromsø |
genre_facet |
EISCAT Tromsø |
op_relation |
Annales Geophysicae -- http://www.bibliothek.uni-regensburg.de/ezeit/?1458425 -- https://www.ann-geophys.net/ -- https://www.ann-geophys.net/volumes.html -- http://link.springer.com/journal/585 -- 1432-0576 https://doi.org/10.1007/s00585-000-1154-z https://noa.gwlb.de/receive/cop_mods_00036675 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00036629/angeo-18-1154-2000.pdf https://angeo.copernicus.org/articles/18/1154/2000/angeo-18-1154-2000.pdf |
op_rights |
https://open-access.net/ uneingeschränkt info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1007/s00585-000-1154-z |
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Annales Geophysicae |
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18 |
container_issue |
9 |
container_start_page |
1154 |
op_container_end_page |
1163 |
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1766400090279247872 |