Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands.
Previous studies of thermokarst lakes have drawn attention to the potential for accumulation of CH₄ under the ice and its subsequent release in spring; however, such observations have not been available for thermokarst waters in carbon‐rich peatlands. Here we undertook a winter profiling of five bla...
Published in: | Journal of Geophysical Research: Biogeosciences |
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ftinrsquebec:oai:espace.inrs.ca:9663 2023-05-15T16:37:17+02:00 Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands. Matveev, Alex Laurion, Isabelle Vincent, Warwick F. 2019 https://espace.inrs.ca/id/eprint/9663/ https://doi.org/10.1029/2019JG005078 unknown Matveev, Alex, Laurion, Isabelle orcid:0000-0001-8694-3330 et Vincent, Warwick F. (2019). Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands. Journal of Geophysical Research: Biogeosciences , vol. 124 , nº 11. p. 3521-3535. DOI:10.1029/2019JG005078 <https://doi.org/10.1029/2019JG005078>. doi:10.1029/2019JG005078 methane permafrost thermokarst oxygen climate change winter mixing Article Évalué par les pairs 2019 ftinrsquebec https://doi.org/10.1029/2019JG005078 2023-02-10T11:45:44Z Previous studies of thermokarst lakes have drawn attention to the potential for accumulation of CH₄ under the ice and its subsequent release in spring; however, such observations have not been available for thermokarst waters in carbon‐rich peatlands. Here we undertook a winter profiling of five black‐water lakes located on eroding permafrost peatlands in subarctic Quebec for comparison with summer profiles and used a 2‐year data set of automated water temperature, conductivity, and oxygen measurements to evaluate how the annual mixing dynamics may affect the venting of greenhouse gases to the atmosphere. All of the sampled lakes contained large amounts of dissolved CH₄ under their winter ice cover. These sub‐ice concentrations were up to 5 orders of magnitude above air equilibrium (i.e., the expected concentration in lake water equilibrated with the atmosphere), resulting in calculated emission rates at ice breakup that would be 1–2 orders of magnitude higher than midsummer averages. The amount of CO₂ dissolved in the water column was reduced in winter, and the estimated ratio of potential diffusive CO₂ to CH₄ emission in spring was half the measured summer ratio, suggesting a seasonal shift in methanogenesis and bacterial activity. All surface lake ice contained bubbles of CH₄ and CO₂, but this amounted to <5% of the total amount of the dissolved CH₄ and CO₂ in the corresponding lake water column. The continuous logging records suggested that lake morphometry may play a role in controlling the timing and extent of CH₄ and CO₂ release from the water column to the atmosphere. Article in Journal/Newspaper Ice permafrost Subarctic Thermokarst Institut national de la recherche scientifique, Québec: Espace INRS Journal of Geophysical Research: Biogeosciences 124 11 3521 3535 |
institution |
Open Polar |
collection |
Institut national de la recherche scientifique, Québec: Espace INRS |
op_collection_id |
ftinrsquebec |
language |
unknown |
topic |
methane permafrost thermokarst oxygen climate change winter mixing |
spellingShingle |
methane permafrost thermokarst oxygen climate change winter mixing Matveev, Alex Laurion, Isabelle Vincent, Warwick F. Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands. |
topic_facet |
methane permafrost thermokarst oxygen climate change winter mixing |
description |
Previous studies of thermokarst lakes have drawn attention to the potential for accumulation of CH₄ under the ice and its subsequent release in spring; however, such observations have not been available for thermokarst waters in carbon‐rich peatlands. Here we undertook a winter profiling of five black‐water lakes located on eroding permafrost peatlands in subarctic Quebec for comparison with summer profiles and used a 2‐year data set of automated water temperature, conductivity, and oxygen measurements to evaluate how the annual mixing dynamics may affect the venting of greenhouse gases to the atmosphere. All of the sampled lakes contained large amounts of dissolved CH₄ under their winter ice cover. These sub‐ice concentrations were up to 5 orders of magnitude above air equilibrium (i.e., the expected concentration in lake water equilibrated with the atmosphere), resulting in calculated emission rates at ice breakup that would be 1–2 orders of magnitude higher than midsummer averages. The amount of CO₂ dissolved in the water column was reduced in winter, and the estimated ratio of potential diffusive CO₂ to CH₄ emission in spring was half the measured summer ratio, suggesting a seasonal shift in methanogenesis and bacterial activity. All surface lake ice contained bubbles of CH₄ and CO₂, but this amounted to <5% of the total amount of the dissolved CH₄ and CO₂ in the corresponding lake water column. The continuous logging records suggested that lake morphometry may play a role in controlling the timing and extent of CH₄ and CO₂ release from the water column to the atmosphere. |
format |
Article in Journal/Newspaper |
author |
Matveev, Alex Laurion, Isabelle Vincent, Warwick F. |
author_facet |
Matveev, Alex Laurion, Isabelle Vincent, Warwick F. |
author_sort |
Matveev, Alex |
title |
Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands. |
title_short |
Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands. |
title_full |
Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands. |
title_fullStr |
Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands. |
title_full_unstemmed |
Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands. |
title_sort |
winter accumulation of methane and its variable timing of release from thermokarst lakes in subarctic peatlands. |
publishDate |
2019 |
url |
https://espace.inrs.ca/id/eprint/9663/ https://doi.org/10.1029/2019JG005078 |
genre |
Ice permafrost Subarctic Thermokarst |
genre_facet |
Ice permafrost Subarctic Thermokarst |
op_relation |
Matveev, Alex, Laurion, Isabelle orcid:0000-0001-8694-3330 et Vincent, Warwick F. (2019). Winter Accumulation of Methane and its Variable Timing of Release from Thermokarst Lakes in Subarctic Peatlands. Journal of Geophysical Research: Biogeosciences , vol. 124 , nº 11. p. 3521-3535. DOI:10.1029/2019JG005078 <https://doi.org/10.1029/2019JG005078>. doi:10.1029/2019JG005078 |
op_doi |
https://doi.org/10.1029/2019JG005078 |
container_title |
Journal of Geophysical Research: Biogeosciences |
container_volume |
124 |
container_issue |
11 |
container_start_page |
3521 |
op_container_end_page |
3535 |
_version_ |
1766027577597624320 |