Radiocarbon distribution and the effect of legacy in lakes of the McMurdo Dry Valleys, Antarctica
The water of the ice‐covered lakes of the McMurdo Dry Valleys is derived primarily from glacial melt streams and to a lesser extent permafrost seeps and subglacial outflow. The result is a mixture of radiocarbon ages that reflect both the end‐member water source and the biogeochemical processing of...
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crwiley:10.4319/lo.2014.59.3.0811 2024-04-28T08:01:01+00:00 Radiocarbon distribution and the effect of legacy in lakes of the McMurdo Dry Valleys, Antarctica Doran, Peter T. Kenig, Fabien Knoepfle, Jennifer Lawson Mikucki, Jill A. Lyons, W. Berry 2014 http://dx.doi.org/10.4319/lo.2014.59.3.0811 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.4319%2Flo.2014.59.3.0811 https://aslopubs.onlinelibrary.wiley.com/doi/pdf/10.4319/lo.2014.59.3.0811 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Limnology and Oceanography volume 59, issue 3, page 811-826 ISSN 0024-3590 1939-5590 Aquatic Science Oceanography journal-article 2014 crwiley https://doi.org/10.4319/lo.2014.59.3.0811 2024-04-08T06:52:44Z The water of the ice‐covered lakes of the McMurdo Dry Valleys is derived primarily from glacial melt streams and to a lesser extent permafrost seeps and subglacial outflow. The result is a mixture of radiocarbon ages that reflect both the end‐member water source and the biogeochemical processing of waters as they migrate to the lake‐water column. Samples were collected from various locations within perennially ice‐covered Antarctic lakes and the streams that feed them, and they were analyzed for radiocarbon abundance of organic and inorganic carbon. Stream gradient and length were shown to affect the degree of equilibration of water with the modern atmosphere prior to entering the lakes. Stream microbial mats assimilate inorganic carbon flowing over them. Seasonal ice‐free ‘moat’ water dissolved inorganic carbon (DIC) is largely dependent on the amount of meltwater input from streams (modern) vs. that from direct glaciers input (old). Under the ice cover, 14 C ages of lake‐water DIC and organic matter are dependent on lake history, composition, and quantity of particulate matter fallout. Bottom waters of the west lobe of Lake Bonney have a DIC age of µ 27,000 14 C yr before present, which we believe are the most radiocarbon‐deficient lake waters on Earth. Comparison of the radiocarbon profiles in the two lobes of Lake Bonney, along with previously published geochemical data, provides a new chronology of the evolution of these two waterbodies and shows that currently deep saline water is being displaced over the sill separating them. Article in Journal/Newspaper Antarc* Antarctic Antarctica Ice McMurdo Dry Valleys permafrost Wiley Online Library Limnology and Oceanography 59 3 811 826 |
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English |
topic |
Aquatic Science Oceanography |
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Aquatic Science Oceanography Doran, Peter T. Kenig, Fabien Knoepfle, Jennifer Lawson Mikucki, Jill A. Lyons, W. Berry Radiocarbon distribution and the effect of legacy in lakes of the McMurdo Dry Valleys, Antarctica |
topic_facet |
Aquatic Science Oceanography |
description |
The water of the ice‐covered lakes of the McMurdo Dry Valleys is derived primarily from glacial melt streams and to a lesser extent permafrost seeps and subglacial outflow. The result is a mixture of radiocarbon ages that reflect both the end‐member water source and the biogeochemical processing of waters as they migrate to the lake‐water column. Samples were collected from various locations within perennially ice‐covered Antarctic lakes and the streams that feed them, and they were analyzed for radiocarbon abundance of organic and inorganic carbon. Stream gradient and length were shown to affect the degree of equilibration of water with the modern atmosphere prior to entering the lakes. Stream microbial mats assimilate inorganic carbon flowing over them. Seasonal ice‐free ‘moat’ water dissolved inorganic carbon (DIC) is largely dependent on the amount of meltwater input from streams (modern) vs. that from direct glaciers input (old). Under the ice cover, 14 C ages of lake‐water DIC and organic matter are dependent on lake history, composition, and quantity of particulate matter fallout. Bottom waters of the west lobe of Lake Bonney have a DIC age of µ 27,000 14 C yr before present, which we believe are the most radiocarbon‐deficient lake waters on Earth. Comparison of the radiocarbon profiles in the two lobes of Lake Bonney, along with previously published geochemical data, provides a new chronology of the evolution of these two waterbodies and shows that currently deep saline water is being displaced over the sill separating them. |
format |
Article in Journal/Newspaper |
author |
Doran, Peter T. Kenig, Fabien Knoepfle, Jennifer Lawson Mikucki, Jill A. Lyons, W. Berry |
author_facet |
Doran, Peter T. Kenig, Fabien Knoepfle, Jennifer Lawson Mikucki, Jill A. Lyons, W. Berry |
author_sort |
Doran, Peter T. |
title |
Radiocarbon distribution and the effect of legacy in lakes of the McMurdo Dry Valleys, Antarctica |
title_short |
Radiocarbon distribution and the effect of legacy in lakes of the McMurdo Dry Valleys, Antarctica |
title_full |
Radiocarbon distribution and the effect of legacy in lakes of the McMurdo Dry Valleys, Antarctica |
title_fullStr |
Radiocarbon distribution and the effect of legacy in lakes of the McMurdo Dry Valleys, Antarctica |
title_full_unstemmed |
Radiocarbon distribution and the effect of legacy in lakes of the McMurdo Dry Valleys, Antarctica |
title_sort |
radiocarbon distribution and the effect of legacy in lakes of the mcmurdo dry valleys, antarctica |
publisher |
Wiley |
publishDate |
2014 |
url |
http://dx.doi.org/10.4319/lo.2014.59.3.0811 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.4319%2Flo.2014.59.3.0811 https://aslopubs.onlinelibrary.wiley.com/doi/pdf/10.4319/lo.2014.59.3.0811 |
genre |
Antarc* Antarctic Antarctica Ice McMurdo Dry Valleys permafrost |
genre_facet |
Antarc* Antarctic Antarctica Ice McMurdo Dry Valleys permafrost |
op_source |
Limnology and Oceanography volume 59, issue 3, page 811-826 ISSN 0024-3590 1939-5590 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.4319/lo.2014.59.3.0811 |
container_title |
Limnology and Oceanography |
container_volume |
59 |
container_issue |
3 |
container_start_page |
811 |
op_container_end_page |
826 |
_version_ |
1797572968889450496 |