The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis
The Arctic Ocean, especially the East Siberian Arctic Shelf (ESAS), has been proposed as a significant source of methane that might play an increasingly important role in the future. However, the underlying processes of formation, removal and transport associated with such emissions are to date stro...
Published in: | Biogeosciences |
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Online Access: | https://pure.au.dk/portal/da/publications/the-origin-of-methane-in-the-east-siberian-arctic-shelf-unraveled-with-triple-isotope-analysis(bbcd30ee-ee1c-4539-af45-203e28eb0b0f).html https://doi.org/10.5194/bg-14-2283-2017 |
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ftuniaarhuspubl:oai:pure.atira.dk:publications/bbcd30ee-ee1c-4539-af45-203e28eb0b0f 2023-05-15T14:26:47+02:00 The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis Sapart, Celia J. Shakhova, Natalia Semiletov, Igor Jansen, Joachim Szidat, Sonke Kosmach, Denis Dudarev, Oleg van der Veen, Carina Egger, Matthias Sergienko, Valentine Salyuk, Anatoly Tumskoy, Vladimir Tison, Jean Louis Rockmann, Thomas 2017-05-05 https://pure.au.dk/portal/da/publications/the-origin-of-methane-in-the-east-siberian-arctic-shelf-unraveled-with-triple-isotope-analysis(bbcd30ee-ee1c-4539-af45-203e28eb0b0f).html https://doi.org/10.5194/bg-14-2283-2017 eng eng info:eu-repo/semantics/restrictedAccess Sapart , C J , Shakhova , N , Semiletov , I , Jansen , J , Szidat , S , Kosmach , D , Dudarev , O , van der Veen , C , Egger , M , Sergienko , V , Salyuk , A , Tumskoy , V , Tison , J L & Rockmann , T 2017 , ' The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis ' , Biogeosciences , vol. 14 , no. 9 , pp. 2283-2292 . https://doi.org/10.5194/bg-14-2283-2017 TERRESTRIAL ORGANIC-MATTER BUOR-KHAYA BAY LAPTEV SEA SUBMARINE PERMAFROST ANAEROBIC OXIDATION CARBON ISOTOPES NE SIBERIA LENA RIVER DEGRADATION WATERS article 2017 ftuniaarhuspubl https://doi.org/10.5194/bg-14-2283-2017 2022-11-23T23:54:59Z The Arctic Ocean, especially the East Siberian Arctic Shelf (ESAS), has been proposed as a significant source of methane that might play an increasingly important role in the future. However, the underlying processes of formation, removal and transport associated with such emissions are to date strongly debated. CH4 concentration and triple isotope composition were analyzed on gas extracted from sediment and water sampled at numerous locations on the shallow ESAS from 2007 to 2013. We find high concentrations (up to 500 mu M) of CH4 in the pore water of the partially thawed subsea permafrost of this region. For all sediment cores, both hydrogen and carbon isotope data reveal the predominant occurrence of CH4 that is not of thermogenic origin as it has long been thought, but resultant from microbial CH4 formation. At some locations, meltwater from buried meteoric ice and/or old organic matter preserved in the subsea permafrost were used as sub-strates. Radiocarbon data demonstrate that the CH4 present in the ESAS sediment is of Pleistocene age or older, but a small contribution of highly C-14-enriched CH4, from unknown origin, prohibits precise age determination for one sediment core and in the water column. Our sediment data suggest that at locations where bubble plumes have been observed, CH4 can escape anaerobic oxidation in the surface sediment. Article in Journal/Newspaper Arctic Arctic Arctic Ocean Ice laptev Laptev Sea lena river permafrost Siberia Aarhus University: Research Arctic Arctic Ocean Buor-Khaya ENVELOPE(127.803,127.803,72.287,72.287) Khaya ENVELOPE(135.167,135.167,60.567,60.567) Laptev Sea Biogeosciences 14 9 2283 2292 |
institution |
Open Polar |
collection |
Aarhus University: Research |
op_collection_id |
ftuniaarhuspubl |
language |
English |
topic |
TERRESTRIAL ORGANIC-MATTER BUOR-KHAYA BAY LAPTEV SEA SUBMARINE PERMAFROST ANAEROBIC OXIDATION CARBON ISOTOPES NE SIBERIA LENA RIVER DEGRADATION WATERS |
spellingShingle |
TERRESTRIAL ORGANIC-MATTER BUOR-KHAYA BAY LAPTEV SEA SUBMARINE PERMAFROST ANAEROBIC OXIDATION CARBON ISOTOPES NE SIBERIA LENA RIVER DEGRADATION WATERS Sapart, Celia J. Shakhova, Natalia Semiletov, Igor Jansen, Joachim Szidat, Sonke Kosmach, Denis Dudarev, Oleg van der Veen, Carina Egger, Matthias Sergienko, Valentine Salyuk, Anatoly Tumskoy, Vladimir Tison, Jean Louis Rockmann, Thomas The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis |
topic_facet |
TERRESTRIAL ORGANIC-MATTER BUOR-KHAYA BAY LAPTEV SEA SUBMARINE PERMAFROST ANAEROBIC OXIDATION CARBON ISOTOPES NE SIBERIA LENA RIVER DEGRADATION WATERS |
description |
The Arctic Ocean, especially the East Siberian Arctic Shelf (ESAS), has been proposed as a significant source of methane that might play an increasingly important role in the future. However, the underlying processes of formation, removal and transport associated with such emissions are to date strongly debated. CH4 concentration and triple isotope composition were analyzed on gas extracted from sediment and water sampled at numerous locations on the shallow ESAS from 2007 to 2013. We find high concentrations (up to 500 mu M) of CH4 in the pore water of the partially thawed subsea permafrost of this region. For all sediment cores, both hydrogen and carbon isotope data reveal the predominant occurrence of CH4 that is not of thermogenic origin as it has long been thought, but resultant from microbial CH4 formation. At some locations, meltwater from buried meteoric ice and/or old organic matter preserved in the subsea permafrost were used as sub-strates. Radiocarbon data demonstrate that the CH4 present in the ESAS sediment is of Pleistocene age or older, but a small contribution of highly C-14-enriched CH4, from unknown origin, prohibits precise age determination for one sediment core and in the water column. Our sediment data suggest that at locations where bubble plumes have been observed, CH4 can escape anaerobic oxidation in the surface sediment. |
format |
Article in Journal/Newspaper |
author |
Sapart, Celia J. Shakhova, Natalia Semiletov, Igor Jansen, Joachim Szidat, Sonke Kosmach, Denis Dudarev, Oleg van der Veen, Carina Egger, Matthias Sergienko, Valentine Salyuk, Anatoly Tumskoy, Vladimir Tison, Jean Louis Rockmann, Thomas |
author_facet |
Sapart, Celia J. Shakhova, Natalia Semiletov, Igor Jansen, Joachim Szidat, Sonke Kosmach, Denis Dudarev, Oleg van der Veen, Carina Egger, Matthias Sergienko, Valentine Salyuk, Anatoly Tumskoy, Vladimir Tison, Jean Louis Rockmann, Thomas |
author_sort |
Sapart, Celia J. |
title |
The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis |
title_short |
The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis |
title_full |
The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis |
title_fullStr |
The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis |
title_full_unstemmed |
The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis |
title_sort |
origin of methane in the east siberian arctic shelf unraveled with triple isotope analysis |
publishDate |
2017 |
url |
https://pure.au.dk/portal/da/publications/the-origin-of-methane-in-the-east-siberian-arctic-shelf-unraveled-with-triple-isotope-analysis(bbcd30ee-ee1c-4539-af45-203e28eb0b0f).html https://doi.org/10.5194/bg-14-2283-2017 |
long_lat |
ENVELOPE(127.803,127.803,72.287,72.287) ENVELOPE(135.167,135.167,60.567,60.567) |
geographic |
Arctic Arctic Ocean Buor-Khaya Khaya Laptev Sea |
geographic_facet |
Arctic Arctic Ocean Buor-Khaya Khaya Laptev Sea |
genre |
Arctic Arctic Arctic Ocean Ice laptev Laptev Sea lena river permafrost Siberia |
genre_facet |
Arctic Arctic Arctic Ocean Ice laptev Laptev Sea lena river permafrost Siberia |
op_source |
Sapart , C J , Shakhova , N , Semiletov , I , Jansen , J , Szidat , S , Kosmach , D , Dudarev , O , van der Veen , C , Egger , M , Sergienko , V , Salyuk , A , Tumskoy , V , Tison , J L & Rockmann , T 2017 , ' The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis ' , Biogeosciences , vol. 14 , no. 9 , pp. 2283-2292 . https://doi.org/10.5194/bg-14-2283-2017 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.5194/bg-14-2283-2017 |
container_title |
Biogeosciences |
container_volume |
14 |
container_issue |
9 |
container_start_page |
2283 |
op_container_end_page |
2292 |
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1766300217631571968 |