Arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft
The Arctic terrestrial and sub-sea permafrost region contains approximately 30 % of the global carbon stock, and therefore understanding Arctic methane emissions and how they might change with a changing climate is important for quantifying the global methane budget and understanding its growth in t...
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ftdoajarticles:oai:doaj.org/article:734acf4b03874f118ecf1d37e592377c 2023-05-15T14:31:47+02:00 Arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft D. S. Sayres R. Dobosy C. Healy E. Dumas J. Kochendorfer J. Munster J. Wilkerson B. Baker J. G. Anderson 2017-07-01T00:00:00Z https://doi.org/10.5194/acp-17-8619-2017 https://doaj.org/article/734acf4b03874f118ecf1d37e592377c EN eng Copernicus Publications https://www.atmos-chem-phys.net/17/8619/2017/acp-17-8619-2017.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-17-8619-2017 1680-7316 1680-7324 https://doaj.org/article/734acf4b03874f118ecf1d37e592377c Atmospheric Chemistry and Physics, Vol 17, Pp 8619-8633 (2017) Physics QC1-999 Chemistry QD1-999 article 2017 ftdoajarticles https://doi.org/10.5194/acp-17-8619-2017 2022-12-31T16:26:59Z The Arctic terrestrial and sub-sea permafrost region contains approximately 30 % of the global carbon stock, and therefore understanding Arctic methane emissions and how they might change with a changing climate is important for quantifying the global methane budget and understanding its growth in the atmosphere. Here we present measurements from a new in situ flux observation system designed for use on a small, low-flying aircraft that was deployed over the North Slope of Alaska during August 2013. The system combines a small methane instrument based on integrated cavity output spectroscopy (ICOS) with an air turbulence probe to calculate methane fluxes based on eddy covariance. We group surface fluxes by land class using a map based on LandSat Thematic Mapper (TM) data with 30 m resolution. We find that wet sedge areas dominate the methane fluxes with a mean flux of 2.1 µg m −2 s −1 during the first part of August. Methane emissions from the Sagavanirktok River have the second highest at almost 1 µg m −2 s −1 . During the second half of August, after soil temperatures had cooled by 7 °C, methane emissions fell to between 0 and 0.5 µg m −2 s −1 for all areas measured. We compare the aircraft measurements with an eddy covariance flux tower located in a wet sedge area and show that the two measurements agree quantitatively when the footprints of both overlap. However, fluxes from sedge vary at times by a factor of 2 or more even within a few kilometers of the tower demonstrating the importance of making regional measurements to map out methane emissions spatial heterogeneity. Aircraft measurements of surface flux can play an important role in bridging the gap between ground-based measurements and regional measurements from remote sensing instruments and models. Article in Journal/Newspaper arctic methane Arctic north slope permafrost Alaska Directory of Open Access Journals: DOAJ Articles Arctic Atmospheric Chemistry and Physics 17 13 8619 8633 |
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Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
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English |
topic |
Physics QC1-999 Chemistry QD1-999 |
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Physics QC1-999 Chemistry QD1-999 D. S. Sayres R. Dobosy C. Healy E. Dumas J. Kochendorfer J. Munster J. Wilkerson B. Baker J. G. Anderson Arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
The Arctic terrestrial and sub-sea permafrost region contains approximately 30 % of the global carbon stock, and therefore understanding Arctic methane emissions and how they might change with a changing climate is important for quantifying the global methane budget and understanding its growth in the atmosphere. Here we present measurements from a new in situ flux observation system designed for use on a small, low-flying aircraft that was deployed over the North Slope of Alaska during August 2013. The system combines a small methane instrument based on integrated cavity output spectroscopy (ICOS) with an air turbulence probe to calculate methane fluxes based on eddy covariance. We group surface fluxes by land class using a map based on LandSat Thematic Mapper (TM) data with 30 m resolution. We find that wet sedge areas dominate the methane fluxes with a mean flux of 2.1 µg m −2 s −1 during the first part of August. Methane emissions from the Sagavanirktok River have the second highest at almost 1 µg m −2 s −1 . During the second half of August, after soil temperatures had cooled by 7 °C, methane emissions fell to between 0 and 0.5 µg m −2 s −1 for all areas measured. We compare the aircraft measurements with an eddy covariance flux tower located in a wet sedge area and show that the two measurements agree quantitatively when the footprints of both overlap. However, fluxes from sedge vary at times by a factor of 2 or more even within a few kilometers of the tower demonstrating the importance of making regional measurements to map out methane emissions spatial heterogeneity. Aircraft measurements of surface flux can play an important role in bridging the gap between ground-based measurements and regional measurements from remote sensing instruments and models. |
format |
Article in Journal/Newspaper |
author |
D. S. Sayres R. Dobosy C. Healy E. Dumas J. Kochendorfer J. Munster J. Wilkerson B. Baker J. G. Anderson |
author_facet |
D. S. Sayres R. Dobosy C. Healy E. Dumas J. Kochendorfer J. Munster J. Wilkerson B. Baker J. G. Anderson |
author_sort |
D. S. Sayres |
title |
Arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft |
title_short |
Arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft |
title_full |
Arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft |
title_fullStr |
Arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft |
title_full_unstemmed |
Arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft |
title_sort |
arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft |
publisher |
Copernicus Publications |
publishDate |
2017 |
url |
https://doi.org/10.5194/acp-17-8619-2017 https://doaj.org/article/734acf4b03874f118ecf1d37e592377c |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
arctic methane Arctic north slope permafrost Alaska |
genre_facet |
arctic methane Arctic north slope permafrost Alaska |
op_source |
Atmospheric Chemistry and Physics, Vol 17, Pp 8619-8633 (2017) |
op_relation |
https://www.atmos-chem-phys.net/17/8619/2017/acp-17-8619-2017.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-17-8619-2017 1680-7316 1680-7324 https://doaj.org/article/734acf4b03874f118ecf1d37e592377c |
op_doi |
https://doi.org/10.5194/acp-17-8619-2017 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
17 |
container_issue |
13 |
container_start_page |
8619 |
op_container_end_page |
8633 |
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1766305319407845376 |