Impact of geomagnetic excursions on atmospheric chemistry and dynamics
Geomagnetic excursions, i.e. short periods in time with much weaker geomagnetic fields and substantial changes in the position of the geomagnetic pole, occurred repeatedly in the Earth's history, e.g. the Laschamp event about 41 kyr ago. Although the next such excursion is certain to come, litt...
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ftunivbern:oai:boris.unibe.ch:58526 2023-08-20T04:02:02+02:00 Impact of geomagnetic excursions on atmospheric chemistry and dynamics Suter, I. Zech, Roland Anet, J. G. Peter, T. 2014 application/pdf https://boris.unibe.ch/58526/1/cp-10-1183-2014.pdf https://boris.unibe.ch/58526/ eng eng Copernicus Publications https://boris.unibe.ch/58526/ info:eu-repo/semantics/openAccess Suter, I.; Zech, Roland; Anet, J. G.; Peter, T. (2014). Impact of geomagnetic excursions on atmospheric chemistry and dynamics. Climate of the past, 10(3), pp. 1183-1194. Copernicus Publications 10.5194/cp-10-1183-2014 <http://dx.doi.org/10.5194/cp-10-1183-2014> 910 Geography & travel info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion PeerReviewed 2014 ftunivbern https://doi.org/10.5194/cp-10-1183-2014 2023-07-31T21:11:24Z Geomagnetic excursions, i.e. short periods in time with much weaker geomagnetic fields and substantial changes in the position of the geomagnetic pole, occurred repeatedly in the Earth's history, e.g. the Laschamp event about 41 kyr ago. Although the next such excursion is certain to come, little is known about the timing and possible consequences for the state of the atmosphere and the ecosystems. Here we use the global chemistry climate model SOCOL-MPIOM to simulate the effects of geomagnetic excursions on atmospheric ionization, chemistry and dynamics. Our simulations show significantly increased concentrations of nitrogen oxides (NOx) in the entire stratosphere, especially over Antarctica (+15%), due to enhanced ionization by galactic cosmic rays. Hydrogen oxides (HOx) are also produced in greater amounts (up to +40%) in the tropical and subtropical lower stratosphere, while their destruction by reactions with enhanced NOx prevails over the poles and in high altitudes (by −5%). Stratospheric ozone concentrations decrease globally above 20 km by 1–2% and at the northern hemispheric tropopause by up to 5% owing to the accelerated NOx-induced destruction. A 5% increase is found in the southern lower stratosphere and troposphere. In response to these changes in ozone and the concomitant changes in atmospheric heating rates, the Arctic vortex intensifies in boreal winter, while the Antarctic vortex weakens in austral winter and spring. Surface wind anomalies show significant intensification of the southern westerlies at their poleward edge during austral winter and a pronounced northward shift in spring. Major impacts on the global climate seem unlikely. Article in Journal/Newspaper Antarc* Antarctic Antarctica Arctic Geomagnetic Pole BORIS (Bern Open Repository and Information System, University of Bern) Antarctic Arctic Austral The Antarctic Climate of the Past 10 3 1183 1194 |
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Open Polar |
collection |
BORIS (Bern Open Repository and Information System, University of Bern) |
op_collection_id |
ftunivbern |
language |
English |
topic |
910 Geography & travel |
spellingShingle |
910 Geography & travel Suter, I. Zech, Roland Anet, J. G. Peter, T. Impact of geomagnetic excursions on atmospheric chemistry and dynamics |
topic_facet |
910 Geography & travel |
description |
Geomagnetic excursions, i.e. short periods in time with much weaker geomagnetic fields and substantial changes in the position of the geomagnetic pole, occurred repeatedly in the Earth's history, e.g. the Laschamp event about 41 kyr ago. Although the next such excursion is certain to come, little is known about the timing and possible consequences for the state of the atmosphere and the ecosystems. Here we use the global chemistry climate model SOCOL-MPIOM to simulate the effects of geomagnetic excursions on atmospheric ionization, chemistry and dynamics. Our simulations show significantly increased concentrations of nitrogen oxides (NOx) in the entire stratosphere, especially over Antarctica (+15%), due to enhanced ionization by galactic cosmic rays. Hydrogen oxides (HOx) are also produced in greater amounts (up to +40%) in the tropical and subtropical lower stratosphere, while their destruction by reactions with enhanced NOx prevails over the poles and in high altitudes (by −5%). Stratospheric ozone concentrations decrease globally above 20 km by 1–2% and at the northern hemispheric tropopause by up to 5% owing to the accelerated NOx-induced destruction. A 5% increase is found in the southern lower stratosphere and troposphere. In response to these changes in ozone and the concomitant changes in atmospheric heating rates, the Arctic vortex intensifies in boreal winter, while the Antarctic vortex weakens in austral winter and spring. Surface wind anomalies show significant intensification of the southern westerlies at their poleward edge during austral winter and a pronounced northward shift in spring. Major impacts on the global climate seem unlikely. |
format |
Article in Journal/Newspaper |
author |
Suter, I. Zech, Roland Anet, J. G. Peter, T. |
author_facet |
Suter, I. Zech, Roland Anet, J. G. Peter, T. |
author_sort |
Suter, I. |
title |
Impact of geomagnetic excursions on atmospheric chemistry and dynamics |
title_short |
Impact of geomagnetic excursions on atmospheric chemistry and dynamics |
title_full |
Impact of geomagnetic excursions on atmospheric chemistry and dynamics |
title_fullStr |
Impact of geomagnetic excursions on atmospheric chemistry and dynamics |
title_full_unstemmed |
Impact of geomagnetic excursions on atmospheric chemistry and dynamics |
title_sort |
impact of geomagnetic excursions on atmospheric chemistry and dynamics |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://boris.unibe.ch/58526/1/cp-10-1183-2014.pdf https://boris.unibe.ch/58526/ |
geographic |
Antarctic Arctic Austral The Antarctic |
geographic_facet |
Antarctic Arctic Austral The Antarctic |
genre |
Antarc* Antarctic Antarctica Arctic Geomagnetic Pole |
genre_facet |
Antarc* Antarctic Antarctica Arctic Geomagnetic Pole |
op_source |
Suter, I.; Zech, Roland; Anet, J. G.; Peter, T. (2014). Impact of geomagnetic excursions on atmospheric chemistry and dynamics. Climate of the past, 10(3), pp. 1183-1194. Copernicus Publications 10.5194/cp-10-1183-2014 <http://dx.doi.org/10.5194/cp-10-1183-2014> |
op_relation |
https://boris.unibe.ch/58526/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/cp-10-1183-2014 |
container_title |
Climate of the Past |
container_volume |
10 |
container_issue |
3 |
container_start_page |
1183 |
op_container_end_page |
1194 |
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1774712413878222848 |