Saturation and hysteresis effects in ionospheric modification experiments observed by the CUTLASS and EISCAT radars
The results of high latitude ionospheric modification experiments utilising the EISCAT heating facility at Tromsø are presented. As a result of the interaction between the high power pump waves and upper hybrid waves in the ionosphere, field-aligned electron density irregularities are artificially e...
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ftdoajarticles:oai:doaj.org/article:3fe2aca500a64d719cc2950faf60db14 2023-05-15T16:04:30+02:00 Saturation and hysteresis effects in ionospheric modification experiments observed by the CUTLASS and EISCAT radars D. M. Wright J. A. Davies T. K. Yeoman T. R. Robinson H. Shergill 2006-03-01T00:00:00Z https://doi.org/10.5194/angeo-24-543-2006 https://doaj.org/article/3fe2aca500a64d719cc2950faf60db14 EN eng Copernicus Publications https://www.ann-geophys.net/24/543/2006/angeo-24-543-2006.pdf https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 doi:10.5194/angeo-24-543-2006 0992-7689 1432-0576 https://doaj.org/article/3fe2aca500a64d719cc2950faf60db14 Annales Geophysicae, Vol 24, Pp 543-553 (2006) Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 article 2006 ftdoajarticles https://doi.org/10.5194/angeo-24-543-2006 2022-12-31T04:35:58Z The results of high latitude ionospheric modification experiments utilising the EISCAT heating facility at Tromsø are presented. As a result of the interaction between the high power pump waves and upper hybrid waves in the ionosphere, field-aligned electron density irregularities are artificially excited. Observations of these structures with the CUTLASS coherent HF radars and the EISCAT incoherent UHF radar exhibit hysteresis effects as the heater output power is varied. These are explained in terms of the two-stage mechanism which leads to the growth of the irregularities. Experiments which involve preconditioning of the ionosphere also indicate that hysteresis could be exploited to maximise the intensity of the field-aligned irregularities, especially where the available heater power is limited. In addition, the saturation of the irregularity amplitude is considered. Although, the rate of irregularity growth becomes less rapid at high heater powers it does not seem to fully saturate, indicating that the amplification would continue beyond the capabilities of the Tromsø heater - currently the most powerful of its kind. It is shown that the CUTLASS radars are sensitive to irregularities produced by very low heater powers (effective radiated powers <4 MW). This fact is discussed from the perspective of a new heating facility, SPEAR, located on Spitzbergen and capable of transmitting high frequency radio waves with an effective radiated power ~10% of that of the Tromsø heater (28MW). Article in Journal/Newspaper EISCAT Spitzbergen Tromsø Directory of Open Access Journals: DOAJ Articles Tromsø Annales Geophysicae 24 2 543 553 |
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 D. M. Wright J. A. Davies T. K. Yeoman T. R. Robinson H. Shergill Saturation and hysteresis effects in ionospheric modification experiments observed by the CUTLASS and EISCAT radars |
topic_facet |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 |
description |
The results of high latitude ionospheric modification experiments utilising the EISCAT heating facility at Tromsø are presented. As a result of the interaction between the high power pump waves and upper hybrid waves in the ionosphere, field-aligned electron density irregularities are artificially excited. Observations of these structures with the CUTLASS coherent HF radars and the EISCAT incoherent UHF radar exhibit hysteresis effects as the heater output power is varied. These are explained in terms of the two-stage mechanism which leads to the growth of the irregularities. Experiments which involve preconditioning of the ionosphere also indicate that hysteresis could be exploited to maximise the intensity of the field-aligned irregularities, especially where the available heater power is limited. In addition, the saturation of the irregularity amplitude is considered. Although, the rate of irregularity growth becomes less rapid at high heater powers it does not seem to fully saturate, indicating that the amplification would continue beyond the capabilities of the Tromsø heater - currently the most powerful of its kind. It is shown that the CUTLASS radars are sensitive to irregularities produced by very low heater powers (effective radiated powers <4 MW). This fact is discussed from the perspective of a new heating facility, SPEAR, located on Spitzbergen and capable of transmitting high frequency radio waves with an effective radiated power ~10% of that of the Tromsø heater (28MW). |
format |
Article in Journal/Newspaper |
author |
D. M. Wright J. A. Davies T. K. Yeoman T. R. Robinson H. Shergill |
author_facet |
D. M. Wright J. A. Davies T. K. Yeoman T. R. Robinson H. Shergill |
author_sort |
D. M. Wright |
title |
Saturation and hysteresis effects in ionospheric modification experiments observed by the CUTLASS and EISCAT radars |
title_short |
Saturation and hysteresis effects in ionospheric modification experiments observed by the CUTLASS and EISCAT radars |
title_full |
Saturation and hysteresis effects in ionospheric modification experiments observed by the CUTLASS and EISCAT radars |
title_fullStr |
Saturation and hysteresis effects in ionospheric modification experiments observed by the CUTLASS and EISCAT radars |
title_full_unstemmed |
Saturation and hysteresis effects in ionospheric modification experiments observed by the CUTLASS and EISCAT radars |
title_sort |
saturation and hysteresis effects in ionospheric modification experiments observed by the cutlass and eiscat radars |
publisher |
Copernicus Publications |
publishDate |
2006 |
url |
https://doi.org/10.5194/angeo-24-543-2006 https://doaj.org/article/3fe2aca500a64d719cc2950faf60db14 |
geographic |
Tromsø |
geographic_facet |
Tromsø |
genre |
EISCAT Spitzbergen Tromsø |
genre_facet |
EISCAT Spitzbergen Tromsø |
op_source |
Annales Geophysicae, Vol 24, Pp 543-553 (2006) |
op_relation |
https://www.ann-geophys.net/24/543/2006/angeo-24-543-2006.pdf https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 doi:10.5194/angeo-24-543-2006 0992-7689 1432-0576 https://doaj.org/article/3fe2aca500a64d719cc2950faf60db14 |
op_doi |
https://doi.org/10.5194/angeo-24-543-2006 |
container_title |
Annales Geophysicae |
container_volume |
24 |
container_issue |
2 |
container_start_page |
543 |
op_container_end_page |
553 |
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1766400086362816512 |