Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea
This study investigates the hydrographic processes involved in setting the maximum wintertime sea ice (SI) extent in the Labrador Sea and Baffin Bay. The analysis is based on an ocean and sea ice state estimate covering the summer-to-summer 1996/97 annual cycle. The estimate is a synthesis of in sit...
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ftmit:oai:dspace.mit.edu:1721.1/82887 2023-06-11T04:09:49+02:00 Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea Fenty, Ian Heimbach, Patrick Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Heimbach, Patrick 2012-10 application/pdf http://hdl.handle.net/1721.1/82887 en_US eng American Meteorological Society http://dx.doi.org/10.1175/JPO-D-12-064.1 Journal of Physical Oceanography 0022-3670 1520-0485 http://hdl.handle.net/1721.1/82887 Fenty, Ian, and Patrick Heimbach. “Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea.” Journal of Physical Oceanography 43, no. 5 (May 2013): 863-883. © 2013 American Meteorological Society orcid:0000-0003-3925-6161 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. American Meteorological Society Article http://purl.org/eprint/type/JournalArticle 2012 ftmit https://doi.org/10.1175/JPO-D-12-064.1 2023-05-29T07:24:53Z This study investigates the hydrographic processes involved in setting the maximum wintertime sea ice (SI) extent in the Labrador Sea and Baffin Bay. The analysis is based on an ocean and sea ice state estimate covering the summer-to-summer 1996/97 annual cycle. The estimate is a synthesis of in situ and satellite hydrographic and ice data with a regional coupled ⅓° ocean–sea ice model. SI advective processes are first demonstrated to be required to reproduce the observed ice extent. With advection, the marginal ice zone (MIZ) location stabilizes where ice melt balances ice mass convergence, a quasi-equilibrium condition achieved via the convergence of warm subtropical-origin subsurface waters into the mixed layer seaward of the MIZ. An analysis of ocean surface buoyancy fluxes reveals a critical role of low-salinity upper ocean (100 m) anomalies for the advancement of SI seaward of the Arctic Water–Irminger Water Thermohaline Front. Anomalous low-salinity waters slow the rate of buoyancy loss–driven mixed layer deepening, shielding an advancing SI pack from the warm subsurface waters, and are conducive to a positive surface meltwater stabilization enhancement (MESEM) feedback driven by SI meltwater release. The low-salinity upper-ocean hydrographic conditions in which the MESEM efficiently operates are termed sea ice–preconditioned waters (SIPW). The SI extent seaward of the Thermohaline Front is shown to closely correspond to the distribution of SIPW. The analysis of two additional state estimates (1992/93, 2003/04) suggests that interannual hydrographic variability provides a first-order explanation for SI maximum extent anomalies in the region. National Science Foundation (U.S.) (Grant ARC-1023499) United States. National Aeronautics and Space Administration (MAP Grant NNX11AQ12G) Article in Journal/Newspaper Arctic Baffin Bay Baffin Bay Baffin Labrador Sea Sea ice DSpace@MIT (Massachusetts Institute of Technology) Arctic Baffin Bay Journal of Physical Oceanography 43 5 863 883 |
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Open Polar |
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DSpace@MIT (Massachusetts Institute of Technology) |
op_collection_id |
ftmit |
language |
English |
description |
This study investigates the hydrographic processes involved in setting the maximum wintertime sea ice (SI) extent in the Labrador Sea and Baffin Bay. The analysis is based on an ocean and sea ice state estimate covering the summer-to-summer 1996/97 annual cycle. The estimate is a synthesis of in situ and satellite hydrographic and ice data with a regional coupled ⅓° ocean–sea ice model. SI advective processes are first demonstrated to be required to reproduce the observed ice extent. With advection, the marginal ice zone (MIZ) location stabilizes where ice melt balances ice mass convergence, a quasi-equilibrium condition achieved via the convergence of warm subtropical-origin subsurface waters into the mixed layer seaward of the MIZ. An analysis of ocean surface buoyancy fluxes reveals a critical role of low-salinity upper ocean (100 m) anomalies for the advancement of SI seaward of the Arctic Water–Irminger Water Thermohaline Front. Anomalous low-salinity waters slow the rate of buoyancy loss–driven mixed layer deepening, shielding an advancing SI pack from the warm subsurface waters, and are conducive to a positive surface meltwater stabilization enhancement (MESEM) feedback driven by SI meltwater release. The low-salinity upper-ocean hydrographic conditions in which the MESEM efficiently operates are termed sea ice–preconditioned waters (SIPW). The SI extent seaward of the Thermohaline Front is shown to closely correspond to the distribution of SIPW. The analysis of two additional state estimates (1992/93, 2003/04) suggests that interannual hydrographic variability provides a first-order explanation for SI maximum extent anomalies in the region. National Science Foundation (U.S.) (Grant ARC-1023499) United States. National Aeronautics and Space Administration (MAP Grant NNX11AQ12G) |
author2 |
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Heimbach, Patrick |
format |
Article in Journal/Newspaper |
author |
Fenty, Ian Heimbach, Patrick |
spellingShingle |
Fenty, Ian Heimbach, Patrick Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea |
author_facet |
Fenty, Ian Heimbach, Patrick |
author_sort |
Fenty, Ian |
title |
Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea |
title_short |
Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea |
title_full |
Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea |
title_fullStr |
Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea |
title_full_unstemmed |
Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea |
title_sort |
hydrographic preconditioning for seasonal sea ice anomalies in the labrador sea |
publisher |
American Meteorological Society |
publishDate |
2012 |
url |
http://hdl.handle.net/1721.1/82887 |
geographic |
Arctic Baffin Bay |
geographic_facet |
Arctic Baffin Bay |
genre |
Arctic Baffin Bay Baffin Bay Baffin Labrador Sea Sea ice |
genre_facet |
Arctic Baffin Bay Baffin Bay Baffin Labrador Sea Sea ice |
op_source |
American Meteorological Society |
op_relation |
http://dx.doi.org/10.1175/JPO-D-12-064.1 Journal of Physical Oceanography 0022-3670 1520-0485 http://hdl.handle.net/1721.1/82887 Fenty, Ian, and Patrick Heimbach. “Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea.” Journal of Physical Oceanography 43, no. 5 (May 2013): 863-883. © 2013 American Meteorological Society orcid:0000-0003-3925-6161 |
op_rights |
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. |
op_doi |
https://doi.org/10.1175/JPO-D-12-064.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
43 |
container_issue |
5 |
container_start_page |
863 |
op_container_end_page |
883 |
_version_ |
1768383827905871872 |