20th century trends and budget implications of chloroform and related tri-and dihalomethanes inferred from firn air
Four trihalomethane (THM; CHCl3, CHBrCl2, CHBr 2Cl and CHBr3) and two dihalomethane (DHM; CH 2BrCl and CH2Br2) trace gases have been measured in air extracted from polar firn collected at the North Greenland Icecore Project (NGRIP) site. CHCl3 was also measured in firn air from Devon Island (DI), Ca...
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2022
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ftinfoscience:oai:infoscience.epfl.ch:298254 2023-05-15T13:43:17+02:00 20th century trends and budget implications of chloroform and related tri-and dihalomethanes inferred from firn air Worton, D. R. Sturges, W. T. Schwander, J. Mulvaney, R. Barnola, J.-M. Chappellaz, J. 2022-11-23T16:10:45Z https://doi.org/10.5194/acp-6-2847-2006 https://infoscience.epfl.ch/record/298254/files/acp-6-2847-2006.pdf http://infoscience.epfl.ch/record/298254 unknown Gottingen, Copernicus GmbH doi:10.5194/acp-6-2847-2006 isi:000238985900001 https://infoscience.epfl.ch/record/298254/files/acp-6-2847-2006.pdf http://infoscience.epfl.ch/record/298254 http://infoscience.epfl.ch/record/298254 Text 2022 ftinfoscience https://doi.org/10.5194/acp-6-2847-2006 2023-02-13T23:12:29Z Four trihalomethane (THM; CHCl3, CHBrCl2, CHBr 2Cl and CHBr3) and two dihalomethane (DHM; CH 2BrCl and CH2Br2) trace gases have been measured in air extracted from polar firn collected at the North Greenland Icecore Project (NGRIP) site. CHCl3 was also measured in firn air from Devon Island (DI), Canada, Dronning Maud Land (DML), Antarctica and Dome Concordia (Dome C), Antarctica. All of these species are believed to be almost entirely of natural origin except for CHCl3 where anthropogenic sources have been reported to contribute ∼10% to the global burden. A 2-D atmospheric model was run for CHCl3 using reported emission estimates to produce historical atmospheric trends at the firn sites, which were then input into a firn diffusion model to produce concentration depth profiles that were compared against the measurements. The anthropogenic emissions were modified in order to give the best model fit to the firn data at NGRIP, Dome C and DML. As a result, the contribution of CHCl3 from anthropogenic sources, mainly from pulp and paper manufacture, to the total chloroform budget appears to have been considerably underestimated and was likely to have been close to ∼50% at the maximum in atmospheric CHCl3 concentrations around 1990, declining to ∼29% at the beginning of the 21st century. We also show that the atmospheric burden of the brominated THM's in the Northern Hemisphere have increased over the 20th century while CH2Br 2 has remained constant over time implying that it is entirely of natural origin. Text Antarc* Antarctica Devon Island DML Dronning Maud Land Greenland NGRIP North Greenland EPFL Infoscience (Ecole Polytechnique Fédérale Lausanne) Dronning Maud Land Canada Greenland Devon Island ENVELOPE(-88.000,-88.000,75.252,75.252) Atmospheric Chemistry and Physics 6 10 2847 2863 |
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Open Polar |
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EPFL Infoscience (Ecole Polytechnique Fédérale Lausanne) |
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ftinfoscience |
language |
unknown |
description |
Four trihalomethane (THM; CHCl3, CHBrCl2, CHBr 2Cl and CHBr3) and two dihalomethane (DHM; CH 2BrCl and CH2Br2) trace gases have been measured in air extracted from polar firn collected at the North Greenland Icecore Project (NGRIP) site. CHCl3 was also measured in firn air from Devon Island (DI), Canada, Dronning Maud Land (DML), Antarctica and Dome Concordia (Dome C), Antarctica. All of these species are believed to be almost entirely of natural origin except for CHCl3 where anthropogenic sources have been reported to contribute ∼10% to the global burden. A 2-D atmospheric model was run for CHCl3 using reported emission estimates to produce historical atmospheric trends at the firn sites, which were then input into a firn diffusion model to produce concentration depth profiles that were compared against the measurements. The anthropogenic emissions were modified in order to give the best model fit to the firn data at NGRIP, Dome C and DML. As a result, the contribution of CHCl3 from anthropogenic sources, mainly from pulp and paper manufacture, to the total chloroform budget appears to have been considerably underestimated and was likely to have been close to ∼50% at the maximum in atmospheric CHCl3 concentrations around 1990, declining to ∼29% at the beginning of the 21st century. We also show that the atmospheric burden of the brominated THM's in the Northern Hemisphere have increased over the 20th century while CH2Br 2 has remained constant over time implying that it is entirely of natural origin. |
format |
Text |
author |
Worton, D. R. Sturges, W. T. Schwander, J. Mulvaney, R. Barnola, J.-M. Chappellaz, J. |
spellingShingle |
Worton, D. R. Sturges, W. T. Schwander, J. Mulvaney, R. Barnola, J.-M. Chappellaz, J. 20th century trends and budget implications of chloroform and related tri-and dihalomethanes inferred from firn air |
author_facet |
Worton, D. R. Sturges, W. T. Schwander, J. Mulvaney, R. Barnola, J.-M. Chappellaz, J. |
author_sort |
Worton, D. R. |
title |
20th century trends and budget implications of chloroform and related tri-and dihalomethanes inferred from firn air |
title_short |
20th century trends and budget implications of chloroform and related tri-and dihalomethanes inferred from firn air |
title_full |
20th century trends and budget implications of chloroform and related tri-and dihalomethanes inferred from firn air |
title_fullStr |
20th century trends and budget implications of chloroform and related tri-and dihalomethanes inferred from firn air |
title_full_unstemmed |
20th century trends and budget implications of chloroform and related tri-and dihalomethanes inferred from firn air |
title_sort |
20th century trends and budget implications of chloroform and related tri-and dihalomethanes inferred from firn air |
publisher |
Gottingen, Copernicus GmbH |
publishDate |
2022 |
url |
https://doi.org/10.5194/acp-6-2847-2006 https://infoscience.epfl.ch/record/298254/files/acp-6-2847-2006.pdf http://infoscience.epfl.ch/record/298254 |
long_lat |
ENVELOPE(-88.000,-88.000,75.252,75.252) |
geographic |
Dronning Maud Land Canada Greenland Devon Island |
geographic_facet |
Dronning Maud Land Canada Greenland Devon Island |
genre |
Antarc* Antarctica Devon Island DML Dronning Maud Land Greenland NGRIP North Greenland |
genre_facet |
Antarc* Antarctica Devon Island DML Dronning Maud Land Greenland NGRIP North Greenland |
op_source |
http://infoscience.epfl.ch/record/298254 |
op_relation |
doi:10.5194/acp-6-2847-2006 isi:000238985900001 https://infoscience.epfl.ch/record/298254/files/acp-6-2847-2006.pdf http://infoscience.epfl.ch/record/298254 |
op_doi |
https://doi.org/10.5194/acp-6-2847-2006 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
6 |
container_issue |
10 |
container_start_page |
2847 |
op_container_end_page |
2863 |
_version_ |
1766186737302765568 |