The dynamical background of polar mesosphere winter echoes from simultaneous EISCAT and ESRAD observations
International audience On 30 October 2004 during a strong solar proton event, layers of enhanced backscatter from altitudes between 55 and 75km have been observed by both ESRAD (52MHz) and the EISCAT VHF (224MHz) radars. These echoes have earlier been termed Polar Mesosphere Winter Echoes, PMWE. Aft...
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ftinsu:oai:HAL:hal-00317706v1 2023-11-12T04:16:35+01:00 The dynamical background of polar mesosphere winter echoes from simultaneous EISCAT and ESRAD observations Belova, E. Kirkwood, S. Ekeberg, J. Osepian, A. Häggström, I. Nilsson, Hans Rietveld, M. Swedish Institute of Space Physics Kiruna (IRF) Polar Geophysical Institute of Russian Academy of Sciences (PGI) Russian Academy of Sciences Moscow (RAS) EISCAT Scientific Association 2005-06-03 https://hal.science/hal-00317706 https://hal.science/hal-00317706/document https://hal.science/hal-00317706/file/angeo-23-1239-2005.pdf en eng HAL CCSD European Geosciences Union hal-00317706 https://hal.science/hal-00317706 https://hal.science/hal-00317706/document https://hal.science/hal-00317706/file/angeo-23-1239-2005.pdf info:eu-repo/semantics/OpenAccess ISSN: 0992-7689 EISSN: 1432-0576 Annales Geophysicae https://hal.science/hal-00317706 Annales Geophysicae, 2005, 23 (4), pp.1239-1247 [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2005 ftinsu 2023-10-25T16:25:13Z International audience On 30 October 2004 during a strong solar proton event, layers of enhanced backscatter from altitudes between 55 and 75km have been observed by both ESRAD (52MHz) and the EISCAT VHF (224MHz) radars. These echoes have earlier been termed Polar Mesosphere Winter Echoes, PMWE. After considering the morphology of the layers and their relation to observed atmospheric waves, we conclude that the radars have likely seen the same phenomenon even though the radars' scattering volumes are located about 220km apart and that the most long-lasting layer is likely associated with wind-shear in an inertio-gravity wave. An ion-chemistry model is used to determine parameters necessary to relate wind-shear induced turbulent energy dissipation rates to radar backscatter. The model is verified by comparison with electron density profiles measured by the EISCAT VHF radar. Observed radar signal strengths are found to be 2-3 orders of magnitude stronger than the maximum which can be expected from neutral turbulence alone, assuming that previously published results relating radar signal scatter to turbulence parameters, and turbulence parameters to wind shear, are correct. The possibility remains that some additional or alternative mechanism may be involved in producing PMWE, such as layers of charged dust/smoke particles or large cluster ions. Article in Journal/Newspaper EISCAT Institut national des sciences de l'Univers: HAL-INSU |
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Open Polar |
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Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
English |
topic |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
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[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Belova, E. Kirkwood, S. Ekeberg, J. Osepian, A. Häggström, I. Nilsson, Hans Rietveld, M. The dynamical background of polar mesosphere winter echoes from simultaneous EISCAT and ESRAD observations |
topic_facet |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience On 30 October 2004 during a strong solar proton event, layers of enhanced backscatter from altitudes between 55 and 75km have been observed by both ESRAD (52MHz) and the EISCAT VHF (224MHz) radars. These echoes have earlier been termed Polar Mesosphere Winter Echoes, PMWE. After considering the morphology of the layers and their relation to observed atmospheric waves, we conclude that the radars have likely seen the same phenomenon even though the radars' scattering volumes are located about 220km apart and that the most long-lasting layer is likely associated with wind-shear in an inertio-gravity wave. An ion-chemistry model is used to determine parameters necessary to relate wind-shear induced turbulent energy dissipation rates to radar backscatter. The model is verified by comparison with electron density profiles measured by the EISCAT VHF radar. Observed radar signal strengths are found to be 2-3 orders of magnitude stronger than the maximum which can be expected from neutral turbulence alone, assuming that previously published results relating radar signal scatter to turbulence parameters, and turbulence parameters to wind shear, are correct. The possibility remains that some additional or alternative mechanism may be involved in producing PMWE, such as layers of charged dust/smoke particles or large cluster ions. |
author2 |
Swedish Institute of Space Physics Kiruna (IRF) Polar Geophysical Institute of Russian Academy of Sciences (PGI) Russian Academy of Sciences Moscow (RAS) EISCAT Scientific Association |
format |
Article in Journal/Newspaper |
author |
Belova, E. Kirkwood, S. Ekeberg, J. Osepian, A. Häggström, I. Nilsson, Hans Rietveld, M. |
author_facet |
Belova, E. Kirkwood, S. Ekeberg, J. Osepian, A. Häggström, I. Nilsson, Hans Rietveld, M. |
author_sort |
Belova, E. |
title |
The dynamical background of polar mesosphere winter echoes from simultaneous EISCAT and ESRAD observations |
title_short |
The dynamical background of polar mesosphere winter echoes from simultaneous EISCAT and ESRAD observations |
title_full |
The dynamical background of polar mesosphere winter echoes from simultaneous EISCAT and ESRAD observations |
title_fullStr |
The dynamical background of polar mesosphere winter echoes from simultaneous EISCAT and ESRAD observations |
title_full_unstemmed |
The dynamical background of polar mesosphere winter echoes from simultaneous EISCAT and ESRAD observations |
title_sort |
dynamical background of polar mesosphere winter echoes from simultaneous eiscat and esrad observations |
publisher |
HAL CCSD |
publishDate |
2005 |
url |
https://hal.science/hal-00317706 https://hal.science/hal-00317706/document https://hal.science/hal-00317706/file/angeo-23-1239-2005.pdf |
genre |
EISCAT |
genre_facet |
EISCAT |
op_source |
ISSN: 0992-7689 EISSN: 1432-0576 Annales Geophysicae https://hal.science/hal-00317706 Annales Geophysicae, 2005, 23 (4), pp.1239-1247 |
op_relation |
hal-00317706 https://hal.science/hal-00317706 https://hal.science/hal-00317706/document https://hal.science/hal-00317706/file/angeo-23-1239-2005.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1782333635416817664 |