Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard
Large reservoirs of methane present in Arctic marine sediments are susceptible to rapid warming, promoting increasing methane emissions. Gas bubbles in the water-column can be detected and flow-rates can be quantified using hydroacoustic survey methods, making it possible to monitor spatiotemporal v...
Published in: | Geophysical Research Letters |
---|---|
Main Authors: | , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
American Geophysical Union (AGU)
2019
|
Subjects: | |
Online Access: | http://hdl.handle.net/10092/17447 https://doi.org/10.1029/2019GL082750 |
id |
ftunivcanter:oai:ir.canterbury.ac.nz:10092/17447 |
---|---|
record_format |
openpolar |
spelling |
ftunivcanter:oai:ir.canterbury.ac.nz:10092/17447 2023-05-15T15:06:31+02:00 Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard Veloso-Alarcon ME Janson P De Batiste M Minshulls TA Westbrook GK Paelike H Bunz S Wright I Greinert J 2019-10-08T21:26:47Z application/pdf http://hdl.handle.net/10092/17447 https://doi.org/10.1029/2019GL082750 English en eng American Geophysical Union (AGU) Veloso-Alarcon ME, Janson P, De Batiste M, Minshulls TA, Westbrook GK, Paelike H, Bunz S, Wright I, Greinert J (2019). Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard. GEOPHYSICAL RESEARCH LETTERS. 46(15). 9072-9081. 0094-8276 1944-8007 http://hdl.handle.net/10092/17447 https://doi.org/10.1029/2019GL082750 Fields of Research::37 - Earth sciences::3705 - Geology::370509 - Sedimentology Fields of Research::37 - Earth sciences::3705 - Geology::370504 - Marine geoscience Field of Research::04 - Earth Sciences::0401 - Atmospheric Sciences::040104 - Climate Change Processes Fields of Research::37 - Earth sciences::3703 - Geochemistry::370304 - Organic geochemistry Journal Article 2019 ftunivcanter https://doi.org/10.1029/2019GL082750 2022-09-08T13:28:38Z Large reservoirs of methane present in Arctic marine sediments are susceptible to rapid warming, promoting increasing methane emissions. Gas bubbles in the water-column can be detected and flow-rates can be quantified using hydroacoustic survey methods, making it possible to monitor spatiotemporal variability. We present methane (CH4) bubble flow-rates derived from hydroacoustic datasets acquired during 11 research expeditions to the western Svalbard continental margin (2008-2014). Three seepage areas emit in total 725–1125 t CH4 y -1 and bubble fluxes are up to 2 kg m-2 y -1 . Bubble fluxes vary between different surveys but no clear trend can be identified. Flux variability analyses suggest that two areas are geologically interconnected, displaying alternating flow changes. Spatial migration of bubble-seepage was observed to follow seasonal changes in the theoretical landward limit of the hydrate stability zone, suggesting that formation/dissociation of shallow hydrates, modulated by bottom water temperatures, influences seafloor bubble release. Article in Journal/Newspaper Arctic Climate change Svalbard University of Canterbury, Christchurch: UC Research Repository Arctic Svalbard Geophysical Research Letters 46 15 9072 9081 |
institution |
Open Polar |
collection |
University of Canterbury, Christchurch: UC Research Repository |
op_collection_id |
ftunivcanter |
language |
English |
topic |
Fields of Research::37 - Earth sciences::3705 - Geology::370509 - Sedimentology Fields of Research::37 - Earth sciences::3705 - Geology::370504 - Marine geoscience Field of Research::04 - Earth Sciences::0401 - Atmospheric Sciences::040104 - Climate Change Processes Fields of Research::37 - Earth sciences::3703 - Geochemistry::370304 - Organic geochemistry |
spellingShingle |
Fields of Research::37 - Earth sciences::3705 - Geology::370509 - Sedimentology Fields of Research::37 - Earth sciences::3705 - Geology::370504 - Marine geoscience Field of Research::04 - Earth Sciences::0401 - Atmospheric Sciences::040104 - Climate Change Processes Fields of Research::37 - Earth sciences::3703 - Geochemistry::370304 - Organic geochemistry Veloso-Alarcon ME Janson P De Batiste M Minshulls TA Westbrook GK Paelike H Bunz S Wright I Greinert J Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard |
topic_facet |
Fields of Research::37 - Earth sciences::3705 - Geology::370509 - Sedimentology Fields of Research::37 - Earth sciences::3705 - Geology::370504 - Marine geoscience Field of Research::04 - Earth Sciences::0401 - Atmospheric Sciences::040104 - Climate Change Processes Fields of Research::37 - Earth sciences::3703 - Geochemistry::370304 - Organic geochemistry |
description |
Large reservoirs of methane present in Arctic marine sediments are susceptible to rapid warming, promoting increasing methane emissions. Gas bubbles in the water-column can be detected and flow-rates can be quantified using hydroacoustic survey methods, making it possible to monitor spatiotemporal variability. We present methane (CH4) bubble flow-rates derived from hydroacoustic datasets acquired during 11 research expeditions to the western Svalbard continental margin (2008-2014). Three seepage areas emit in total 725–1125 t CH4 y -1 and bubble fluxes are up to 2 kg m-2 y -1 . Bubble fluxes vary between different surveys but no clear trend can be identified. Flux variability analyses suggest that two areas are geologically interconnected, displaying alternating flow changes. Spatial migration of bubble-seepage was observed to follow seasonal changes in the theoretical landward limit of the hydrate stability zone, suggesting that formation/dissociation of shallow hydrates, modulated by bottom water temperatures, influences seafloor bubble release. |
format |
Article in Journal/Newspaper |
author |
Veloso-Alarcon ME Janson P De Batiste M Minshulls TA Westbrook GK Paelike H Bunz S Wright I Greinert J |
author_facet |
Veloso-Alarcon ME Janson P De Batiste M Minshulls TA Westbrook GK Paelike H Bunz S Wright I Greinert J |
author_sort |
Veloso-Alarcon ME |
title |
Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard |
title_short |
Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard |
title_full |
Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard |
title_fullStr |
Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard |
title_full_unstemmed |
Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard |
title_sort |
variability of acoustically evidenced methane bubble emissions offshore western svalbard |
publisher |
American Geophysical Union (AGU) |
publishDate |
2019 |
url |
http://hdl.handle.net/10092/17447 https://doi.org/10.1029/2019GL082750 |
geographic |
Arctic Svalbard |
geographic_facet |
Arctic Svalbard |
genre |
Arctic Climate change Svalbard |
genre_facet |
Arctic Climate change Svalbard |
op_relation |
Veloso-Alarcon ME, Janson P, De Batiste M, Minshulls TA, Westbrook GK, Paelike H, Bunz S, Wright I, Greinert J (2019). Variability of Acoustically Evidenced Methane Bubble Emissions Offshore Western Svalbard. GEOPHYSICAL RESEARCH LETTERS. 46(15). 9072-9081. 0094-8276 1944-8007 http://hdl.handle.net/10092/17447 https://doi.org/10.1029/2019GL082750 |
op_doi |
https://doi.org/10.1029/2019GL082750 |
container_title |
Geophysical Research Letters |
container_volume |
46 |
container_issue |
15 |
container_start_page |
9072 |
op_container_end_page |
9081 |
_version_ |
1766338107416772608 |