Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling
Methane stored in seabed reservoirs such as methane hydrates can reach the atmosphere in the form of bubbles or dissolved in water. Hydrates could destabilize with rising temperature further increasing greenhouse gas emissions in a warming climate. To assess the impact of oceanic emissions from the...
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ftunivcam:oai:www.repository.cam.ac.uk:1810/262439 2024-02-04T09:56:59+01:00 Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling Pisso, I Myhre, CL Platt, SM Eckhardt, S Hermansen, O Schmidbauer, N Mienert, J Vadakkepuliyambatta, S Bauguitte, S Pitt, J Allen, G Bower, KN O'Shea, S Gallagher, MW Percival, CJ Pyle, J Cain, M Stohl, A 2016-12-16 application/pdf https://www.repository.cam.ac.uk/handle/1810/262439 https://doi.org/10.17863/CAM.7703 eng eng AGU Publications http://dx.doi.org/10.1002/2016jd025590 Journal of Geophysical Research: Atmospheres https://www.repository.cam.ac.uk/handle/1810/262439 doi:10.17863/CAM.7703 Attribution 4.0 International http://creativecommons.org/licenses/by/4.0/ 37 Earth Sciences 3701 Atmospheric Sciences 13 Climate Action Article 2016 ftunivcam https://doi.org/10.17863/CAM.7703 2024-01-11T23:19:18Z Methane stored in seabed reservoirs such as methane hydrates can reach the atmosphere in the form of bubbles or dissolved in water. Hydrates could destabilize with rising temperature further increasing greenhouse gas emissions in a warming climate. To assess the impact of oceanic emissions from the area west of Svalbard, where methane hydrates are abundant, we used measurements collected with a research aircraft (Facility for Airborne Atmospheric Measurements) and a ship (Helmer Hansen) during the Summer 2014 and for Zeppelin Observatory for the full year. We present a model-supported analysis of the atmospheric CH$_{4}$mixing ratios measured by the different platforms. To address uncertainty about where CH$_{4}$ emissions actually occur, we explored three scenarios: areas with known seeps, a hydrate stability model, and an ocean depth criterion. We then used a budget analysis and a Lagrangian particle dispersion model to compare measurements taken upwind and downwind of the potential CH$_{4}$ emission areas. We found small differences between the CH$_{4}$ mixing ratios measured upwind and downwind of the potential emission areas during the campaign. By taking into account measurement and sampling uncertainties and by determining the sensitivity of the measured mixing ratios to potential oceanic emissions, we provide upper limits for the CH$_{4}$ fluxes. The CH$_{4}$ flux during the campaign was small, with an upper limit of 2.5 nmol m$^{-2}$ s$^{-1}$ in the stability model scenario. The Zeppelin Observatory data for 2014 suggest CH$_{4}$ fluxes from the Svalbard continental platform below 0.2 Tg yr$^{-1}$. All estimates are in the lower range of values previously reported. MOCA—Methane Emissions from the Arctic OCean to the Atmosphere: Present and Future Climate Effects is funded by the Research Council of Norway, grant 225814. CAGE—Centre for Arctic Gas Hydrate, Environment and Climate research work was supported by the Research Council of Norway through its Centres of Excellence funding scheme grant 223259. ... Article in Journal/Newspaper Arctic Gas Hydrate, Environment and Climate Arctic Arctic Ocean Svalbard Apollo - University of Cambridge Repository Arctic Arctic Ocean Svalbard Norway |
institution |
Open Polar |
collection |
Apollo - University of Cambridge Repository |
op_collection_id |
ftunivcam |
language |
English |
topic |
37 Earth Sciences 3701 Atmospheric Sciences 13 Climate Action |
spellingShingle |
37 Earth Sciences 3701 Atmospheric Sciences 13 Climate Action Pisso, I Myhre, CL Platt, SM Eckhardt, S Hermansen, O Schmidbauer, N Mienert, J Vadakkepuliyambatta, S Bauguitte, S Pitt, J Allen, G Bower, KN O'Shea, S Gallagher, MW Percival, CJ Pyle, J Cain, M Stohl, A Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling |
topic_facet |
37 Earth Sciences 3701 Atmospheric Sciences 13 Climate Action |
description |
Methane stored in seabed reservoirs such as methane hydrates can reach the atmosphere in the form of bubbles or dissolved in water. Hydrates could destabilize with rising temperature further increasing greenhouse gas emissions in a warming climate. To assess the impact of oceanic emissions from the area west of Svalbard, where methane hydrates are abundant, we used measurements collected with a research aircraft (Facility for Airborne Atmospheric Measurements) and a ship (Helmer Hansen) during the Summer 2014 and for Zeppelin Observatory for the full year. We present a model-supported analysis of the atmospheric CH$_{4}$mixing ratios measured by the different platforms. To address uncertainty about where CH$_{4}$ emissions actually occur, we explored three scenarios: areas with known seeps, a hydrate stability model, and an ocean depth criterion. We then used a budget analysis and a Lagrangian particle dispersion model to compare measurements taken upwind and downwind of the potential CH$_{4}$ emission areas. We found small differences between the CH$_{4}$ mixing ratios measured upwind and downwind of the potential emission areas during the campaign. By taking into account measurement and sampling uncertainties and by determining the sensitivity of the measured mixing ratios to potential oceanic emissions, we provide upper limits for the CH$_{4}$ fluxes. The CH$_{4}$ flux during the campaign was small, with an upper limit of 2.5 nmol m$^{-2}$ s$^{-1}$ in the stability model scenario. The Zeppelin Observatory data for 2014 suggest CH$_{4}$ fluxes from the Svalbard continental platform below 0.2 Tg yr$^{-1}$. All estimates are in the lower range of values previously reported. MOCA—Methane Emissions from the Arctic OCean to the Atmosphere: Present and Future Climate Effects is funded by the Research Council of Norway, grant 225814. CAGE—Centre for Arctic Gas Hydrate, Environment and Climate research work was supported by the Research Council of Norway through its Centres of Excellence funding scheme grant 223259. ... |
format |
Article in Journal/Newspaper |
author |
Pisso, I Myhre, CL Platt, SM Eckhardt, S Hermansen, O Schmidbauer, N Mienert, J Vadakkepuliyambatta, S Bauguitte, S Pitt, J Allen, G Bower, KN O'Shea, S Gallagher, MW Percival, CJ Pyle, J Cain, M Stohl, A |
author_facet |
Pisso, I Myhre, CL Platt, SM Eckhardt, S Hermansen, O Schmidbauer, N Mienert, J Vadakkepuliyambatta, S Bauguitte, S Pitt, J Allen, G Bower, KN O'Shea, S Gallagher, MW Percival, CJ Pyle, J Cain, M Stohl, A |
author_sort |
Pisso, I |
title |
Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling |
title_short |
Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling |
title_full |
Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling |
title_fullStr |
Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling |
title_full_unstemmed |
Constraints on oceanic methane emissions west of Svalbard from atmospheric in situ measurements and Lagrangian transport modeling |
title_sort |
constraints on oceanic methane emissions west of svalbard from atmospheric in situ measurements and lagrangian transport modeling |
publisher |
AGU Publications |
publishDate |
2016 |
url |
https://www.repository.cam.ac.uk/handle/1810/262439 https://doi.org/10.17863/CAM.7703 |
geographic |
Arctic Arctic Ocean Svalbard Norway |
geographic_facet |
Arctic Arctic Ocean Svalbard Norway |
genre |
Arctic Gas Hydrate, Environment and Climate Arctic Arctic Ocean Svalbard |
genre_facet |
Arctic Gas Hydrate, Environment and Climate Arctic Arctic Ocean Svalbard |
op_relation |
https://www.repository.cam.ac.uk/handle/1810/262439 doi:10.17863/CAM.7703 |
op_rights |
Attribution 4.0 International http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.17863/CAM.7703 |
_version_ |
1789961297982390272 |