A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis
Methane (CH4) is the second most important anthropogenic greenhouse gas in the atmosphere. Rapid variations of the CH4 concentration, as frequently registered, for example, during the last ice age, have been used as reliable time markers for the definition of a common time scale of polar ice cores....
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ftunivbern:oai:boris.unibe.ch:37499 2023-08-20T04:00:18+02:00 A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis Schüpbach, Simon Federer, Urs Kaufmann, Patrik R. Hutterli, Manuel A. Buiron, Daphné Blunier, Thomas Fischer, Hubertus Stocker, Thomas F. 2009 application/pdf https://boris.unibe.ch/37499/1/es9003137.pdf https://boris.unibe.ch/37499/ eng eng ACS Publications https://boris.unibe.ch/37499/ info:eu-repo/semantics/restrictedAccess Schüpbach, Simon; Federer, Urs; Kaufmann, Patrik R.; Hutterli, Manuel A.; Buiron, Daphné; Blunier, Thomas; Fischer, Hubertus; Stocker, Thomas F. (2009). A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis. Environmental science & technology, 43(14), pp. 5371-5376. Washington, D.C.: ACS Publications 10.1021/es9003137 <http://dx.doi.org/10.1021/es9003137> 530 Physics info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion PeerReviewed 2009 ftunivbern https://doi.org/10.1021/es9003137 2023-07-31T20:59:35Z Methane (CH4) is the second most important anthropogenic greenhouse gas in the atmosphere. Rapid variations of the CH4 concentration, as frequently registered, for example, during the last ice age, have been used as reliable time markers for the definition of a common time scale of polar ice cores. In addition, these variations indicate changes in the sources of methane primarily associated with the presence of wetlands. In order to determine the exact time evolution of such fast concentration changes, CH4 measurements of the highest resolution in the ice core archive are required. Here, we present a new, semicontinuous and field-deployable CH4 detection method, which was incorporated in a continuous flow analysis (CFA) system. In CFA, samples cut along the axis of an ice core are melted at a melt speed of typically 3.5 cm/min. The air from bubbles in the ice core is extracted continuously from the meltwater and forwarded to a gas chromatograph (GC) for high-resolution CH4 measurements. The GC performs a measurement every 3.5 min, hence, a depth resolution of 15 cm is achieved at the chosen melt rate. An even higher resolution is not necessary due to the low pass filtering of air in ice cores caused by the slow bubble enclosure process and the diffusion of air in firn. Reproducibility of the new method is 3%, thus, for a typical CH4 concentration of 500 ppb during an ice age, this corresponds to an absolute precision of 15 ppb, comparable to traditional analyses on discrete samples. Results of CFA-CH4 measurements on the ice core from Talos Dome (Antarctica) illustrate the much higher temporal resolution of our method compared with established melt-refreeze CH4 measurements and demonstrate the feasibility of the new method. Article in Journal/Newspaper Antarc* Antarctica ice core BORIS (Bern Open Repository and Information System, University of Bern) Talos Dome ENVELOPE(158.000,158.000,-73.000,-73.000) Environmental Science & Technology 43 14 5371 5376 |
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Open Polar |
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BORIS (Bern Open Repository and Information System, University of Bern) |
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ftunivbern |
language |
English |
topic |
530 Physics |
spellingShingle |
530 Physics Schüpbach, Simon Federer, Urs Kaufmann, Patrik R. Hutterli, Manuel A. Buiron, Daphné Blunier, Thomas Fischer, Hubertus Stocker, Thomas F. A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis |
topic_facet |
530 Physics |
description |
Methane (CH4) is the second most important anthropogenic greenhouse gas in the atmosphere. Rapid variations of the CH4 concentration, as frequently registered, for example, during the last ice age, have been used as reliable time markers for the definition of a common time scale of polar ice cores. In addition, these variations indicate changes in the sources of methane primarily associated with the presence of wetlands. In order to determine the exact time evolution of such fast concentration changes, CH4 measurements of the highest resolution in the ice core archive are required. Here, we present a new, semicontinuous and field-deployable CH4 detection method, which was incorporated in a continuous flow analysis (CFA) system. In CFA, samples cut along the axis of an ice core are melted at a melt speed of typically 3.5 cm/min. The air from bubbles in the ice core is extracted continuously from the meltwater and forwarded to a gas chromatograph (GC) for high-resolution CH4 measurements. The GC performs a measurement every 3.5 min, hence, a depth resolution of 15 cm is achieved at the chosen melt rate. An even higher resolution is not necessary due to the low pass filtering of air in ice cores caused by the slow bubble enclosure process and the diffusion of air in firn. Reproducibility of the new method is 3%, thus, for a typical CH4 concentration of 500 ppb during an ice age, this corresponds to an absolute precision of 15 ppb, comparable to traditional analyses on discrete samples. Results of CFA-CH4 measurements on the ice core from Talos Dome (Antarctica) illustrate the much higher temporal resolution of our method compared with established melt-refreeze CH4 measurements and demonstrate the feasibility of the new method. |
format |
Article in Journal/Newspaper |
author |
Schüpbach, Simon Federer, Urs Kaufmann, Patrik R. Hutterli, Manuel A. Buiron, Daphné Blunier, Thomas Fischer, Hubertus Stocker, Thomas F. |
author_facet |
Schüpbach, Simon Federer, Urs Kaufmann, Patrik R. Hutterli, Manuel A. Buiron, Daphné Blunier, Thomas Fischer, Hubertus Stocker, Thomas F. |
author_sort |
Schüpbach, Simon |
title |
A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis |
title_short |
A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis |
title_full |
A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis |
title_fullStr |
A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis |
title_full_unstemmed |
A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis |
title_sort |
new method for high resolution methane measurements on polar ice cores using continuous flow analysis |
publisher |
ACS Publications |
publishDate |
2009 |
url |
https://boris.unibe.ch/37499/1/es9003137.pdf https://boris.unibe.ch/37499/ |
long_lat |
ENVELOPE(158.000,158.000,-73.000,-73.000) |
geographic |
Talos Dome |
geographic_facet |
Talos Dome |
genre |
Antarc* Antarctica ice core |
genre_facet |
Antarc* Antarctica ice core |
op_source |
Schüpbach, Simon; Federer, Urs; Kaufmann, Patrik R.; Hutterli, Manuel A.; Buiron, Daphné; Blunier, Thomas; Fischer, Hubertus; Stocker, Thomas F. (2009). A new method for high resolution methane measurements on polar ice cores using Continuous Flow Analysis. Environmental science & technology, 43(14), pp. 5371-5376. Washington, D.C.: ACS Publications 10.1021/es9003137 <http://dx.doi.org/10.1021/es9003137> |
op_relation |
https://boris.unibe.ch/37499/ |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1021/es9003137 |
container_title |
Environmental Science & Technology |
container_volume |
43 |
container_issue |
14 |
container_start_page |
5371 |
op_container_end_page |
5376 |
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1774717465633226752 |