On the relationship of energetic particle precipitation and mesopause temperature
Energetic particle precipitation (EPP) has the potential to change the neutral atmospheric temperature in the mesopause region. However, recent results are inconsistent, leaving the mechanism and the actual effect still unresolved. In this study we have searched for electron precipitation events and...
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ftdoajarticles:oai:doaj.org/article:c0d662f5e2eb40139f0899a221064a83 2023-05-15T16:04:49+02:00 On the relationship of energetic particle precipitation and mesopause temperature F. Enengl N. Partamies N. Ivchenko L. Baddeley 2021-09-01T00:00:00Z https://doi.org/10.5194/angeo-39-795-2021 https://doaj.org/article/c0d662f5e2eb40139f0899a221064a83 EN eng Copernicus Publications https://angeo.copernicus.org/articles/39/795/2021/angeo-39-795-2021.pdf https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 doi:10.5194/angeo-39-795-2021 0992-7689 1432-0576 https://doaj.org/article/c0d662f5e2eb40139f0899a221064a83 Annales Geophysicae, Vol 39, Pp 795-809 (2021) Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 article 2021 ftdoajarticles https://doi.org/10.5194/angeo-39-795-2021 2022-12-31T07:09:05Z Energetic particle precipitation (EPP) has the potential to change the neutral atmospheric temperature in the mesopause region. However, recent results are inconsistent, leaving the mechanism and the actual effect still unresolved. In this study we have searched for electron precipitation events and investigated a possible correlation between D-region electron density enhancements and simultaneous neutral temperature changes. The rotational temperature of the excited hydroxyl (OH) molecules is retrieved from the infrared spectrum of the OH airglow. The electron density is monitored by the European Incoherent Scatter Scientific Association (EISCAT) Svalbard Radar. We use all available experiments from the International Polar Year (IPY) in 2007–2008 until February 2019. Particle precipitation events are characterized by rapid increases in electron density by a factor of 4 at an altitude range of 80–95 km, which overlaps with the nominal altitude of the infrared OH airglow layer. The OH airglow measurements and the electron density measurements are co-located. Six of the 10 analysed electron precipitation events are associated with a temperature decrease of 10–20 K. Four events were related to a temperature change of less than 10 K. We interpret the results in terms of the change in the chemical composition in the mesosphere. Due to EPP ionization the population of excited OH at the top of the airglow layer may decrease. As a consequence, the airglow peak height changes and the temperatures are probed at lower altitudes. The observed change in temperature thus depends on the behaviour of the vertical temperature profile within the airglow layer. This is in agreement with conclusions of earlier studies but is, for the first time, constructed from electron precipitation measurements as opposed to proxies. The EPP-related temperature change recovers very fast, typically within less than 60 min. We therefore further conclude that this type of EPP event reaching the mesopause region would only have a significant impact ... Article in Journal/Newspaper EISCAT International Polar Year IPY Svalbard Directory of Open Access Journals: DOAJ Articles Svalbard Annales Geophysicae 39 5 795 809 |
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 F. Enengl N. Partamies N. Ivchenko L. Baddeley On the relationship of energetic particle precipitation and mesopause temperature |
topic_facet |
Science Q Physics QC1-999 Geophysics. Cosmic physics QC801-809 |
description |
Energetic particle precipitation (EPP) has the potential to change the neutral atmospheric temperature in the mesopause region. However, recent results are inconsistent, leaving the mechanism and the actual effect still unresolved. In this study we have searched for electron precipitation events and investigated a possible correlation between D-region electron density enhancements and simultaneous neutral temperature changes. The rotational temperature of the excited hydroxyl (OH) molecules is retrieved from the infrared spectrum of the OH airglow. The electron density is monitored by the European Incoherent Scatter Scientific Association (EISCAT) Svalbard Radar. We use all available experiments from the International Polar Year (IPY) in 2007–2008 until February 2019. Particle precipitation events are characterized by rapid increases in electron density by a factor of 4 at an altitude range of 80–95 km, which overlaps with the nominal altitude of the infrared OH airglow layer. The OH airglow measurements and the electron density measurements are co-located. Six of the 10 analysed electron precipitation events are associated with a temperature decrease of 10–20 K. Four events were related to a temperature change of less than 10 K. We interpret the results in terms of the change in the chemical composition in the mesosphere. Due to EPP ionization the population of excited OH at the top of the airglow layer may decrease. As a consequence, the airglow peak height changes and the temperatures are probed at lower altitudes. The observed change in temperature thus depends on the behaviour of the vertical temperature profile within the airglow layer. This is in agreement with conclusions of earlier studies but is, for the first time, constructed from electron precipitation measurements as opposed to proxies. The EPP-related temperature change recovers very fast, typically within less than 60 min. We therefore further conclude that this type of EPP event reaching the mesopause region would only have a significant impact ... |
format |
Article in Journal/Newspaper |
author |
F. Enengl N. Partamies N. Ivchenko L. Baddeley |
author_facet |
F. Enengl N. Partamies N. Ivchenko L. Baddeley |
author_sort |
F. Enengl |
title |
On the relationship of energetic particle precipitation and mesopause temperature |
title_short |
On the relationship of energetic particle precipitation and mesopause temperature |
title_full |
On the relationship of energetic particle precipitation and mesopause temperature |
title_fullStr |
On the relationship of energetic particle precipitation and mesopause temperature |
title_full_unstemmed |
On the relationship of energetic particle precipitation and mesopause temperature |
title_sort |
on the relationship of energetic particle precipitation and mesopause temperature |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://doi.org/10.5194/angeo-39-795-2021 https://doaj.org/article/c0d662f5e2eb40139f0899a221064a83 |
geographic |
Svalbard |
geographic_facet |
Svalbard |
genre |
EISCAT International Polar Year IPY Svalbard |
genre_facet |
EISCAT International Polar Year IPY Svalbard |
op_source |
Annales Geophysicae, Vol 39, Pp 795-809 (2021) |
op_relation |
https://angeo.copernicus.org/articles/39/795/2021/angeo-39-795-2021.pdf https://doaj.org/toc/0992-7689 https://doaj.org/toc/1432-0576 doi:10.5194/angeo-39-795-2021 0992-7689 1432-0576 https://doaj.org/article/c0d662f5e2eb40139f0899a221064a83 |
op_doi |
https://doi.org/10.5194/angeo-39-795-2021 |
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Annales Geophysicae |
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39 |
container_issue |
5 |
container_start_page |
795 |
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809 |
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