High spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the Tromsø heater
The CUTLASS Finland HF radar has been operated in conjunction with the EISCAT Tromsø RF ionospheric heater facility to examine a ULF wave characteristic of the development of a field line resonance (FLR) driven by a cavity mode caused by a magnetospheric impulse. When the heater is on, striating the...
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ftdoajarticles:oai:doaj.org/article:e9137030898445b4b9915fffe3d115ae 2023-05-15T16:04:48+02:00 High spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the Tromsø heater T. K. Yeoman D. M. Wright T. R. Robinson J. A. Davies M. Rietveld 1997-06-01T00:00:00Z https://doi.org/10.1007/s00585-997-0634-9 https://doaj.org/article/e9137030898445b4b9915fffe3d115ae EN eng Copernicus Publications https://www.ann-geophys.net/15/634/1997/angeo-15-634-1997.pdf https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 doi:10.1007/s00585-997-0634-9 0992-7689 1432-0576 https://doaj.org/article/e9137030898445b4b9915fffe3d115ae Annales Geophysicae, Vol 15, Pp 634-644 (1997) Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 article 1997 ftdoajarticles https://doi.org/10.1007/s00585-997-0634-9 2022-12-31T01:28:27Z The CUTLASS Finland HF radar has been operated in conjunction with the EISCAT Tromsø RF ionospheric heater facility to examine a ULF wave characteristic of the development of a field line resonance (FLR) driven by a cavity mode caused by a magnetospheric impulse. When the heater is on, striating the ionosphere with field-aligned ionospheric electron density irregularities, a large enough radar target is generated to allow post-integration over only 1 second. When combined with 15 km range gates, this gives radar measurements of a naturally occurring ULF wave at a far better temporal and spatial resolution than has been achieved previously. The time-dependent signature of the ULF wave has been examined as it evolves from a large-scale cavity resonance, through a transient where the wave period was latitude-dependent and the oscillation had the characteristics of freely ringing field lines, and finally to a very narrow, small-scale local field line resonance. The resonance width of the FLR is only 60 km and this is compared with previous observations and theory. The FLR wave signature is strongly attenuated in the ground magnetometer data. The characterisation of the impulse driven FLR was only achieved very crudely with the ground magnetometer data and, in fact, an accurate determination of the properties of the cavity and field line resonant systems challenges the currently available limitations of ionospheric radar techniques. The combination of the latest ionospheric radars and facilities such as the Tromsø ionospheric heater can result in a powerful new tool for geophysical research. Article in Journal/Newspaper EISCAT Tromsø Directory of Open Access Journals: DOAJ Articles Tromsø Annales Geophysicae 15 6 634 644 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 |
spellingShingle |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 T. K. Yeoman D. M. Wright T. R. Robinson J. A. Davies M. Rietveld High spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the Tromsø heater |
topic_facet |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 |
description |
The CUTLASS Finland HF radar has been operated in conjunction with the EISCAT Tromsø RF ionospheric heater facility to examine a ULF wave characteristic of the development of a field line resonance (FLR) driven by a cavity mode caused by a magnetospheric impulse. When the heater is on, striating the ionosphere with field-aligned ionospheric electron density irregularities, a large enough radar target is generated to allow post-integration over only 1 second. When combined with 15 km range gates, this gives radar measurements of a naturally occurring ULF wave at a far better temporal and spatial resolution than has been achieved previously. The time-dependent signature of the ULF wave has been examined as it evolves from a large-scale cavity resonance, through a transient where the wave period was latitude-dependent and the oscillation had the characteristics of freely ringing field lines, and finally to a very narrow, small-scale local field line resonance. The resonance width of the FLR is only 60 km and this is compared with previous observations and theory. The FLR wave signature is strongly attenuated in the ground magnetometer data. The characterisation of the impulse driven FLR was only achieved very crudely with the ground magnetometer data and, in fact, an accurate determination of the properties of the cavity and field line resonant systems challenges the currently available limitations of ionospheric radar techniques. The combination of the latest ionospheric radars and facilities such as the Tromsø ionospheric heater can result in a powerful new tool for geophysical research. |
format |
Article in Journal/Newspaper |
author |
T. K. Yeoman D. M. Wright T. R. Robinson J. A. Davies M. Rietveld |
author_facet |
T. K. Yeoman D. M. Wright T. R. Robinson J. A. Davies M. Rietveld |
author_sort |
T. K. Yeoman |
title |
High spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the Tromsø heater |
title_short |
High spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the Tromsø heater |
title_full |
High spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the Tromsø heater |
title_fullStr |
High spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the Tromsø heater |
title_full_unstemmed |
High spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the Tromsø heater |
title_sort |
high spatial and temporal resolution observations of an impulse-driven field line resonance in radar backscatter artificially generated with the tromsø heater |
publisher |
Copernicus Publications |
publishDate |
1997 |
url |
https://doi.org/10.1007/s00585-997-0634-9 https://doaj.org/article/e9137030898445b4b9915fffe3d115ae |
geographic |
Tromsø |
geographic_facet |
Tromsø |
genre |
EISCAT Tromsø |
genre_facet |
EISCAT Tromsø |
op_source |
Annales Geophysicae, Vol 15, Pp 634-644 (1997) |
op_relation |
https://www.ann-geophys.net/15/634/1997/angeo-15-634-1997.pdf https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 doi:10.1007/s00585-997-0634-9 0992-7689 1432-0576 https://doaj.org/article/e9137030898445b4b9915fffe3d115ae |
op_doi |
https://doi.org/10.1007/s00585-997-0634-9 |
container_title |
Annales Geophysicae |
container_volume |
15 |
container_issue |
6 |
container_start_page |
634 |
op_container_end_page |
644 |
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1766400436382728192 |