Determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model
We have used the Whole Atmosphere Community Climate Model (WACCM), with an updated treatment of loss processes, to determine the atmospheric lifetime of sulfur hexafluoride (SF 6 ). The model includes the following SF 6 removal processes: photolysis, electron attachment and reaction with mesospheric...
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ftcopernicus:oai:publications.copernicus.org:acp53944 2023-05-15T18:20:18+02:00 Determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model Kovács, Tamás Feng, Wuhu Totterdill, Anna Plane, John M. C. Dhomse, Sandip Gómez-Martín, Juan Carlos Stiller, Gabriele P. Haenel, Florian J. Smith, Christopher Forster, Piers M. García, Rolando R. Marsh, Daniel R. Chipperfield, Martyn P. 2018-09-16 application/pdf https://doi.org/10.5194/acp-17-883-2017 https://www.atmos-chem-phys.net/17/883/2017/ eng eng doi:10.5194/acp-17-883-2017 https://www.atmos-chem-phys.net/17/883/2017/ eISSN: 1680-7324 Text 2018 ftcopernicus https://doi.org/10.5194/acp-17-883-2017 2019-12-24T09:51:43Z We have used the Whole Atmosphere Community Climate Model (WACCM), with an updated treatment of loss processes, to determine the atmospheric lifetime of sulfur hexafluoride (SF 6 ). The model includes the following SF 6 removal processes: photolysis, electron attachment and reaction with mesospheric metal atoms. The Sodankylä Ion Chemistry (SIC) model is incorporated into the standard version of WACCM to produce a new version with a detailed D region ion chemistry with cluster ions and negative ions. This is used to determine a latitude- and altitude-dependent scaling factor for the electron density in the standard WACCM in order to carry out multi-year SF 6 simulations. The model gives a mean SF 6 lifetime over an 11-year solar cycle ( τ ) of 1278 years (with a range from 1120 to 1475 years), which is much shorter than the currently widely used value of 3200 years, due to the larger contribution (97.4 %) of the modelled electron density to the total atmospheric loss. The loss of SF 6 by reaction with mesospheric metal atoms (Na and K) is far too slow to affect the lifetime. We investigate how this shorter atmospheric lifetime impacts the use of SF 6 to derive stratospheric age of air. The age of air derived from this shorter lifetime SF 6 tracer is longer by 9 % in polar latitudes at 20 km compared to a passive SF 6 tracer. We also present laboratory measurements of the infrared spectrum of SF 6 and find good agreement with previous studies. We calculate the resulting radiative forcings and efficiencies to be, on average, very similar to those reported previously. Our values for the 20-, 100- and 500-year global warming potentials are 18 000, 23 800 and 31 300, respectively. Text Sodankylä Copernicus Publications: E-Journals Sodankylä ENVELOPE(26.600,26.600,67.417,67.417) Atmospheric Chemistry and Physics 17 2 883 898 |
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Open Polar |
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Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
We have used the Whole Atmosphere Community Climate Model (WACCM), with an updated treatment of loss processes, to determine the atmospheric lifetime of sulfur hexafluoride (SF 6 ). The model includes the following SF 6 removal processes: photolysis, electron attachment and reaction with mesospheric metal atoms. The Sodankylä Ion Chemistry (SIC) model is incorporated into the standard version of WACCM to produce a new version with a detailed D region ion chemistry with cluster ions and negative ions. This is used to determine a latitude- and altitude-dependent scaling factor for the electron density in the standard WACCM in order to carry out multi-year SF 6 simulations. The model gives a mean SF 6 lifetime over an 11-year solar cycle ( τ ) of 1278 years (with a range from 1120 to 1475 years), which is much shorter than the currently widely used value of 3200 years, due to the larger contribution (97.4 %) of the modelled electron density to the total atmospheric loss. The loss of SF 6 by reaction with mesospheric metal atoms (Na and K) is far too slow to affect the lifetime. We investigate how this shorter atmospheric lifetime impacts the use of SF 6 to derive stratospheric age of air. The age of air derived from this shorter lifetime SF 6 tracer is longer by 9 % in polar latitudes at 20 km compared to a passive SF 6 tracer. We also present laboratory measurements of the infrared spectrum of SF 6 and find good agreement with previous studies. We calculate the resulting radiative forcings and efficiencies to be, on average, very similar to those reported previously. Our values for the 20-, 100- and 500-year global warming potentials are 18 000, 23 800 and 31 300, respectively. |
format |
Text |
author |
Kovács, Tamás Feng, Wuhu Totterdill, Anna Plane, John M. C. Dhomse, Sandip Gómez-Martín, Juan Carlos Stiller, Gabriele P. Haenel, Florian J. Smith, Christopher Forster, Piers M. García, Rolando R. Marsh, Daniel R. Chipperfield, Martyn P. |
spellingShingle |
Kovács, Tamás Feng, Wuhu Totterdill, Anna Plane, John M. C. Dhomse, Sandip Gómez-Martín, Juan Carlos Stiller, Gabriele P. Haenel, Florian J. Smith, Christopher Forster, Piers M. García, Rolando R. Marsh, Daniel R. Chipperfield, Martyn P. Determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model |
author_facet |
Kovács, Tamás Feng, Wuhu Totterdill, Anna Plane, John M. C. Dhomse, Sandip Gómez-Martín, Juan Carlos Stiller, Gabriele P. Haenel, Florian J. Smith, Christopher Forster, Piers M. García, Rolando R. Marsh, Daniel R. Chipperfield, Martyn P. |
author_sort |
Kovács, Tamás |
title |
Determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model |
title_short |
Determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model |
title_full |
Determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model |
title_fullStr |
Determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model |
title_full_unstemmed |
Determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model |
title_sort |
determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model |
publishDate |
2018 |
url |
https://doi.org/10.5194/acp-17-883-2017 https://www.atmos-chem-phys.net/17/883/2017/ |
long_lat |
ENVELOPE(26.600,26.600,67.417,67.417) |
geographic |
Sodankylä |
geographic_facet |
Sodankylä |
genre |
Sodankylä |
genre_facet |
Sodankylä |
op_source |
eISSN: 1680-7324 |
op_relation |
doi:10.5194/acp-17-883-2017 https://www.atmos-chem-phys.net/17/883/2017/ |
op_doi |
https://doi.org/10.5194/acp-17-883-2017 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
17 |
container_issue |
2 |
container_start_page |
883 |
op_container_end_page |
898 |
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1766197818663370752 |