Freshwater Discharge, Sediment Transport, and Modeled Climate Impacts of the Final Drainage of Glacial Lake Agassiz
A cold event at around 8200 calendar years BP and the release, at around that time, of a huge freshwater outburst from ice-dammed glacial Lake Agassiz have lent support to the idea that the flood triggered the cold event. Some suggest that the freshwater addition caused a weakening of the North Atla...
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| Format: | Article |
| Language: | en_US |
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American Meteorological Society
2010
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| Online Access: | http://hdl.handle.net/1721.1/52530 https://orcid.org/0000-0002-7936-7256 |
| _version_ | 1811089152780795904 |
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| author | Bush, John W. M. |
| author2 | Massachusetts Institute of Technology. Department of Mathematics |
| author_facet | Massachusetts Institute of Technology. Department of Mathematics Bush, John W. M. |
| author_sort | Bush, John W. M. |
| collection | MIT |
| description | A cold event at around 8200 calendar years BP and the release, at around that time, of a huge freshwater outburst from ice-dammed glacial Lake Agassiz have lent support to the idea that the flood triggered the cold event. Some suggest that the freshwater addition caused a weakening of the North Atlantic meridional overturning circulation (MOC) thereby reducing the ocean transport of heat to high northern latitudes. Although several modeling efforts lend strength to this claim, the paleoceanographic record is equivocal. The authors’ aim is to use a coupled ocean–atmosphere model to examine the possibility that the two events are causally linked but that MOC reduction was not the main agent of change. It is found that the outburst flood and associated redirection of postflood meltwater drainage to the Labrador Sea, via Hudson Strait, can freshen the North Atlantic, leading to reduced salinity and sea surface temperature, and thus to increased sea ice production at high latitudes. The results point to the possibility that the preflood outflow to the St. Lawrence was extremely turbid and sufficiently dense to become hyperpycnal, whereas the postflood outflow through Hudson Strait had a lower load of suspended sediment and was buoyant. |
| first_indexed | 2024-09-23T14:14:31Z |
| format | Article |
| id | mit-1721.1/52530 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T14:14:31Z |
| publishDate | 2010 |
| publisher | American Meteorological Society |
| record_format | dspace |
| spelling | mit-1721.1/525302022-10-01T20:02:32Z Freshwater Discharge, Sediment Transport, and Modeled Climate Impacts of the Final Drainage of Glacial Lake Agassiz Bush, John W. M. Massachusetts Institute of Technology. Department of Mathematics Bush, John W. M. Bush, John W. M. Canadian Institute for Advanced Research Natural Sciences and Engineering Research Council of Canada Canadian Foundation for Climate and Atmospheric Sciences (CFCAS) A cold event at around 8200 calendar years BP and the release, at around that time, of a huge freshwater outburst from ice-dammed glacial Lake Agassiz have lent support to the idea that the flood triggered the cold event. Some suggest that the freshwater addition caused a weakening of the North Atlantic meridional overturning circulation (MOC) thereby reducing the ocean transport of heat to high northern latitudes. Although several modeling efforts lend strength to this claim, the paleoceanographic record is equivocal. The authors’ aim is to use a coupled ocean–atmosphere model to examine the possibility that the two events are causally linked but that MOC reduction was not the main agent of change. It is found that the outburst flood and associated redirection of postflood meltwater drainage to the Labrador Sea, via Hudson Strait, can freshen the North Atlantic, leading to reduced salinity and sea surface temperature, and thus to increased sea ice production at high latitudes. The results point to the possibility that the preflood outflow to the St. Lawrence was extremely turbid and sufficiently dense to become hyperpycnal, whereas the postflood outflow through Hudson Strait had a lower load of suspended sediment and was buoyant. 2010-03-11T21:34:59Z 2010-03-11T21:34:59Z 2009-04 2008-10 Article http://purl.org/eprint/type/JournalArticle 0894-8755 http://hdl.handle.net/1721.1/52530 Clarke, Garry K. C., Andrew B. G. Bush, and John W. M. Bush. “Freshwater Discharge, Sediment Transport, and Modeled Climate Impacts of the Final Drainage of Glacial Lake Agassiz.” Journal of Climate 22.8 (2009): 2161-2180. © 2009 American Meteorological Society https://orcid.org/0000-0002-7936-7256 en_US http://dx.doi.org/10.1175/2008JCLI2439.1 Journal of Climate Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Meteorological Society American Meteorological Society |
| spellingShingle | Canadian Institute for Advanced Research Natural Sciences and Engineering Research Council of Canada Canadian Foundation for Climate and Atmospheric Sciences (CFCAS) Bush, John W. M. Freshwater Discharge, Sediment Transport, and Modeled Climate Impacts of the Final Drainage of Glacial Lake Agassiz |
| title | Freshwater Discharge, Sediment Transport, and Modeled Climate Impacts of the Final Drainage of Glacial Lake Agassiz |
| title_full | Freshwater Discharge, Sediment Transport, and Modeled Climate Impacts of the Final Drainage of Glacial Lake Agassiz |
| title_fullStr | Freshwater Discharge, Sediment Transport, and Modeled Climate Impacts of the Final Drainage of Glacial Lake Agassiz |
| title_full_unstemmed | Freshwater Discharge, Sediment Transport, and Modeled Climate Impacts of the Final Drainage of Glacial Lake Agassiz |
| title_short | Freshwater Discharge, Sediment Transport, and Modeled Climate Impacts of the Final Drainage of Glacial Lake Agassiz |
| title_sort | freshwater discharge sediment transport and modeled climate impacts of the final drainage of glacial lake agassiz |
| topic | Canadian Institute for Advanced Research Natural Sciences and Engineering Research Council of Canada Canadian Foundation for Climate and Atmospheric Sciences (CFCAS) |
| url | http://hdl.handle.net/1721.1/52530 https://orcid.org/0000-0002-7936-7256 |
| work_keys_str_mv | AT bushjohnwm freshwaterdischargesedimenttransportandmodeledclimateimpactsofthefinaldrainageofglaciallakeagassiz |