Ice-sheet-driven methane storage and release in the Arctic

Published version. Source at http://dx.doi.org/10.1038/ncomms10314 A manuscript version of this article is part of Aleksei Portnov's Ph.D. thesis, which is available in Munin at http://hdl.handle.net/10037/8220 It is established that late-twentieth and twenty-first century ocean warming has forc...

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Published in:Nature Communications
Main Authors: Portnov, Aleksei D, Vadakkepuliyambatta, Sunil, Mienert, Jurgen, Hubbard, Alun Lloyd
Format: Article in Journal/Newspaper
Language:English
Published: Nature Publishing Group 2016
Subjects:
Online Access:https://hdl.handle.net/10037/10695
https://doi.org/10.1038/ncomms10314
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author Portnov, Aleksei D
Vadakkepuliyambatta, Sunil
Mienert, Jurgen
Hubbard, Alun Lloyd
author_facet Portnov, Aleksei D
Vadakkepuliyambatta, Sunil
Mienert, Jurgen
Hubbard, Alun Lloyd
author_sort Portnov, Aleksei D
collection University of Tromsø: Munin Open Research Archive
container_issue 1
container_title Nature Communications
container_volume 7
description Published version. Source at http://dx.doi.org/10.1038/ncomms10314 A manuscript version of this article is part of Aleksei Portnov's Ph.D. thesis, which is available in Munin at http://hdl.handle.net/10037/8220 It is established that late-twentieth and twenty-first century ocean warming has forced dissociation of gas hydrates with concomitant seabed methane release. However, recent dating of methane expulsion sites suggests that gas release has been ongoing over many millennia. Here we synthesize observations of B1,900 fluid escape features—pockmarks and active gas flares—across a previously glaciated Arctic margin with ice-sheet thermomechanical and gas hydrate stability zone modelling. Our results indicate that even under conservative estimates of ice thickness with temperate subglacial conditions, a 500-m thick gas hydrate stability zone—which could serve as a methane sink—existed beneath the ice sheet. Moreover, we reveal that in water depths 150–520 m methane release also per- sisted through a 20-km-wide window between the subsea and subglacial gas hydrate stability zone. This window expanded in response to post-glacial climate warming and deglaciation thereby opening the Arctic shelf for methane release.
format Article in Journal/Newspaper
genre Arctic
Ice Sheet
genre_facet Arctic
Ice Sheet
geographic Arctic
geographic_facet Arctic
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spelling ftunivtroemsoe:oai:munin.uit.no:10037/10695 2025-04-13T14:13:36+00:00 Ice-sheet-driven methane storage and release in the Arctic Portnov, Aleksei D Vadakkepuliyambatta, Sunil Mienert, Jurgen Hubbard, Alun Lloyd 2016-01-07 https://hdl.handle.net/10037/10695 https://doi.org/10.1038/ncomms10314 eng eng Nature Publishing Group Nature Communications info:eu-repo/grantAgreement/NRC/SFF/223259/Jurisdiction/CAGE// FRIDAID 1301756 doi:10.1038/ncomms10314 https://hdl.handle.net/10037/10695 openAccess VDP::Matematikk og Naturvitenskap: 400::Geofag: 450 VDP::Mathematics and natural science: 400::Geosciences: 450 Journal article Tidsskriftartikkel Peer reviewed 2016 ftunivtroemsoe https://doi.org/10.1038/ncomms10314 2025-03-14T05:17:56Z Published version. Source at http://dx.doi.org/10.1038/ncomms10314 A manuscript version of this article is part of Aleksei Portnov's Ph.D. thesis, which is available in Munin at http://hdl.handle.net/10037/8220 It is established that late-twentieth and twenty-first century ocean warming has forced dissociation of gas hydrates with concomitant seabed methane release. However, recent dating of methane expulsion sites suggests that gas release has been ongoing over many millennia. Here we synthesize observations of B1,900 fluid escape features—pockmarks and active gas flares—across a previously glaciated Arctic margin with ice-sheet thermomechanical and gas hydrate stability zone modelling. Our results indicate that even under conservative estimates of ice thickness with temperate subglacial conditions, a 500-m thick gas hydrate stability zone—which could serve as a methane sink—existed beneath the ice sheet. Moreover, we reveal that in water depths 150–520 m methane release also per- sisted through a 20-km-wide window between the subsea and subglacial gas hydrate stability zone. This window expanded in response to post-glacial climate warming and deglaciation thereby opening the Arctic shelf for methane release. Article in Journal/Newspaper Arctic Ice Sheet University of Tromsø: Munin Open Research Archive Arctic Nature Communications 7 1
spellingShingle VDP::Matematikk og Naturvitenskap: 400::Geofag: 450
VDP::Mathematics and natural science: 400::Geosciences: 450
Portnov, Aleksei D
Vadakkepuliyambatta, Sunil
Mienert, Jurgen
Hubbard, Alun Lloyd
Ice-sheet-driven methane storage and release in the Arctic
title Ice-sheet-driven methane storage and release in the Arctic
title_full Ice-sheet-driven methane storage and release in the Arctic
title_fullStr Ice-sheet-driven methane storage and release in the Arctic
title_full_unstemmed Ice-sheet-driven methane storage and release in the Arctic
title_short Ice-sheet-driven methane storage and release in the Arctic
title_sort ice-sheet-driven methane storage and release in the arctic
topic VDP::Matematikk og Naturvitenskap: 400::Geofag: 450
VDP::Mathematics and natural science: 400::Geosciences: 450
topic_facet VDP::Matematikk og Naturvitenskap: 400::Geofag: 450
VDP::Mathematics and natural science: 400::Geosciences: 450
url https://hdl.handle.net/10037/10695
https://doi.org/10.1038/ncomms10314