Transport of methane in open talik thermokarst lakes in discontinuous permafrost aquifers in Interior Alaska 2015-2017
As northern regions of the world experience warming climate, scientists look to permafrost, a crucial component of arctic and subarctic ecosystems, as a source and sink of atmospheric carbon. It is well-known that the thawing of permafrost from above as a result of warming climate is a considerable...
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dataone:doi:10.18739/A2HX15R89 2024-06-03T18:46:42+00:00 Transport of methane in open talik thermokarst lakes in discontinuous permafrost aquifers in Interior Alaska 2015-2017 Bridget Eckhardt Goldstream Valley, northwest of Fairbanks, Alaska. ENVELOPE(-147.97284,-147.81308,64.93289,64.88055) BEGINDATE: 2015-01-01T00:00:00Z ENDDATE: 2017-01-01T00:00:00Z 2020-01-01T00:00:00Z https://doi.org/10.18739/A2HX15R89 unknown Arctic Data Center thermokarst discontinuous permafrost methane Dataset 2020 dataone:urn:node:ARCTIC https://doi.org/10.18739/A2HX15R89 2024-06-03T18:17:00Z As northern regions of the world experience warming climate, scientists look to permafrost, a crucial component of arctic and subarctic ecosystems, as a source and sink of atmospheric carbon. It is well-known that the thawing of permafrost from above as a result of warming climate is a considerable source of greenhouse gases. However, few studies have considered the production of methane, a potent greenhouse gas, beneath the permafrost. A rugged permafrost bottom is proposed to favor the storage of gas in "pockets" that have been formed through permafrost thaw and degradation from below. Sub (below)-permafrost methane can migrate to reach the atmosphere when connections between the sub-permafrost and supra- permafrost opens pathways from the pocket to the bottom of an open talik lake. We hypothesized that the migration of methane occurs through advection and diffusion as a dissolved gas and by movement as an immiscible fluid. Through measurement of environmental tracers in two thermokarst lakes in Goldstream Creek Basin, Fairbanks, Alaska, from 2015 to 2017, we found that advection was variable and was seasonally and climatically dependent demonstrating both upward and downward groundwater flow within our study lakes. Measurements of dissolved methane concentrations in the lakes demonstrated that diffusion of methane was not a significant transport mechanism in the groundwater-to-lake pathway due to the extreme temporal and spatial variability of methane concentrations. Immiscible flow of free-phase methane is likely the dominant transport mechanism but is dependent on the lake sediment composition and the formation of secondary pathways within the talik. Data obtained from this study allowed for a better understanding of methane transport and thermokarst lake dynamics. Dataset Arctic permafrost Subarctic Thermokarst Alaska Arctic Data Center (via DataONE) Arctic Fairbanks Talik ENVELOPE(146.601,146.601,59.667,59.667) ENVELOPE(-147.97284,-147.81308,64.93289,64.88055) |
institution |
Open Polar |
collection |
Arctic Data Center (via DataONE) |
op_collection_id |
dataone:urn:node:ARCTIC |
language |
unknown |
topic |
thermokarst discontinuous permafrost methane |
spellingShingle |
thermokarst discontinuous permafrost methane Bridget Eckhardt Transport of methane in open talik thermokarst lakes in discontinuous permafrost aquifers in Interior Alaska 2015-2017 |
topic_facet |
thermokarst discontinuous permafrost methane |
description |
As northern regions of the world experience warming climate, scientists look to permafrost, a crucial component of arctic and subarctic ecosystems, as a source and sink of atmospheric carbon. It is well-known that the thawing of permafrost from above as a result of warming climate is a considerable source of greenhouse gases. However, few studies have considered the production of methane, a potent greenhouse gas, beneath the permafrost. A rugged permafrost bottom is proposed to favor the storage of gas in "pockets" that have been formed through permafrost thaw and degradation from below. Sub (below)-permafrost methane can migrate to reach the atmosphere when connections between the sub-permafrost and supra- permafrost opens pathways from the pocket to the bottom of an open talik lake. We hypothesized that the migration of methane occurs through advection and diffusion as a dissolved gas and by movement as an immiscible fluid. Through measurement of environmental tracers in two thermokarst lakes in Goldstream Creek Basin, Fairbanks, Alaska, from 2015 to 2017, we found that advection was variable and was seasonally and climatically dependent demonstrating both upward and downward groundwater flow within our study lakes. Measurements of dissolved methane concentrations in the lakes demonstrated that diffusion of methane was not a significant transport mechanism in the groundwater-to-lake pathway due to the extreme temporal and spatial variability of methane concentrations. Immiscible flow of free-phase methane is likely the dominant transport mechanism but is dependent on the lake sediment composition and the formation of secondary pathways within the talik. Data obtained from this study allowed for a better understanding of methane transport and thermokarst lake dynamics. |
format |
Dataset |
author |
Bridget Eckhardt |
author_facet |
Bridget Eckhardt |
author_sort |
Bridget Eckhardt |
title |
Transport of methane in open talik thermokarst lakes in discontinuous permafrost aquifers in Interior Alaska 2015-2017 |
title_short |
Transport of methane in open talik thermokarst lakes in discontinuous permafrost aquifers in Interior Alaska 2015-2017 |
title_full |
Transport of methane in open talik thermokarst lakes in discontinuous permafrost aquifers in Interior Alaska 2015-2017 |
title_fullStr |
Transport of methane in open talik thermokarst lakes in discontinuous permafrost aquifers in Interior Alaska 2015-2017 |
title_full_unstemmed |
Transport of methane in open talik thermokarst lakes in discontinuous permafrost aquifers in Interior Alaska 2015-2017 |
title_sort |
transport of methane in open talik thermokarst lakes in discontinuous permafrost aquifers in interior alaska 2015-2017 |
publisher |
Arctic Data Center |
publishDate |
2020 |
url |
https://doi.org/10.18739/A2HX15R89 |
op_coverage |
Goldstream Valley, northwest of Fairbanks, Alaska. ENVELOPE(-147.97284,-147.81308,64.93289,64.88055) BEGINDATE: 2015-01-01T00:00:00Z ENDDATE: 2017-01-01T00:00:00Z |
long_lat |
ENVELOPE(146.601,146.601,59.667,59.667) ENVELOPE(-147.97284,-147.81308,64.93289,64.88055) |
geographic |
Arctic Fairbanks Talik |
geographic_facet |
Arctic Fairbanks Talik |
genre |
Arctic permafrost Subarctic Thermokarst Alaska |
genre_facet |
Arctic permafrost Subarctic Thermokarst Alaska |
op_doi |
https://doi.org/10.18739/A2HX15R89 |
_version_ |
1800869904626221056 |