Oceanic Boundary Conditions for Jakobshavn Glacier. Part I: Variability and Renewal of Ilulissat Icefjord Waters, 2001–14
Jakobshavn Glacier, west Greenland, has responded to temperature changes in Ilulissat Icefjord, into which it terminates. This study collected hydrographic observations inside Ilulissat Icefjord and from adjacent Disko Bay between 2001 and 2014. The warmest deep Disko Bay waters were blocked by the...
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| Format: | Article |
| Language: | en_US |
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American Meteorological Society
2015
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| Online Access: | http://hdl.handle.net/1721.1/97579 https://orcid.org/0000-0002-3694-9942 |
| _version_ | 1826215928090591232 |
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| author | Holland, David M. Rosing-Asvid, Aqqalu Behrens, Jane W. Boje, Jesper Gladish, Carl |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Holland, David M. Rosing-Asvid, Aqqalu Behrens, Jane W. Boje, Jesper Gladish, Carl |
| author_sort | Holland, David M. |
| collection | MIT |
| description | Jakobshavn Glacier, west Greenland, has responded to temperature changes in Ilulissat Icefjord, into which it terminates. This study collected hydrographic observations inside Ilulissat Icefjord and from adjacent Disko Bay between 2001 and 2014. The warmest deep Disko Bay waters were blocked by the entrance sill and did not reach Jakobshavn Glacier. In the fjord basin, the summer mean temperature was 2.8°C from 2009 to 2013, excluding 2010, when it was 1°C cooler. Despite this variability, summer potential densities in the basin were in the narrow range of 27.20 ≤ σ[subscript θ] ≤ 27.31 kg m[superscript −3], and basin water properties matched those of Disko Bay in this layer each summer. This relation has likely held since at least 1980. Basin waters from 2009 and 2011–13 were therefore similar to those in 1998/99, when Jakobshavn Glacier began to retreat, while basin waters in 2010 were as cool as in the 1980s. The 2010 basin temperature anomaly was advected into Disko Bay, not produced by local atmospheric variability.
This anomaly also shows that Ilulissat Icefjord basin waters were renewed annually or faster. Time series fragments inside the fjord did not capture the 2010 anomaly but show that the basin temperatures varied little subannually, outside of summer. Fjord velocity profiles from summer 2013 implied a basin renewal time scale of about 1 month. In model simulations of the fjord circulation, subglacial discharge from Jakobshavn Glacier could drive renewal of the fjord basin over a single summer, while baroclinic forcing from outside the fjord could not, because of the sill at the mouth. |
| first_indexed | 2024-09-23T16:39:15Z |
| format | Article |
| id | mit-1721.1/97579 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T16:39:15Z |
| publishDate | 2015 |
| publisher | American Meteorological Society |
| record_format | dspace |
| spelling | mit-1721.1/975792022-09-29T20:33:55Z Oceanic Boundary Conditions for Jakobshavn Glacier. Part I: Variability and Renewal of Ilulissat Icefjord Waters, 2001–14 Holland, David M. Rosing-Asvid, Aqqalu Behrens, Jane W. Boje, Jesper Gladish, Carl Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Gladish, Carl Jakobshavn Glacier, west Greenland, has responded to temperature changes in Ilulissat Icefjord, into which it terminates. This study collected hydrographic observations inside Ilulissat Icefjord and from adjacent Disko Bay between 2001 and 2014. The warmest deep Disko Bay waters were blocked by the entrance sill and did not reach Jakobshavn Glacier. In the fjord basin, the summer mean temperature was 2.8°C from 2009 to 2013, excluding 2010, when it was 1°C cooler. Despite this variability, summer potential densities in the basin were in the narrow range of 27.20 ≤ σ[subscript θ] ≤ 27.31 kg m[superscript −3], and basin water properties matched those of Disko Bay in this layer each summer. This relation has likely held since at least 1980. Basin waters from 2009 and 2011–13 were therefore similar to those in 1998/99, when Jakobshavn Glacier began to retreat, while basin waters in 2010 were as cool as in the 1980s. The 2010 basin temperature anomaly was advected into Disko Bay, not produced by local atmospheric variability. This anomaly also shows that Ilulissat Icefjord basin waters were renewed annually or faster. Time series fragments inside the fjord did not capture the 2010 anomaly but show that the basin temperatures varied little subannually, outside of summer. Fjord velocity profiles from summer 2013 implied a basin renewal time scale of about 1 month. In model simulations of the fjord circulation, subglacial discharge from Jakobshavn Glacier could drive renewal of the fjord basin over a single summer, while baroclinic forcing from outside the fjord could not, because of the sill at the mouth. 2015-06-30T15:09:11Z 2015-06-30T15:09:11Z 2015-01 2014-10 Article http://purl.org/eprint/type/JournalArticle 0022-3670 1520-0485 http://hdl.handle.net/1721.1/97579 Gladish, Carl V., David M. Holland, Aqqalu Rosing-Asvid, Jane W. Behrens, and Jesper Boje. “Oceanic Boundary Conditions for Jakobshavn Glacier. Part I: Variability and Renewal of Ilulissat Icefjord Waters, 2001–14.” J. Phys. Oceanogr. 45, no. 1 (January 2015): 3–32. © 2015 American Meteorological Society https://orcid.org/0000-0002-3694-9942 en_US http://dx.doi.org/10.1175/JPO-D-14-0044.1 Journal of Physical Oceanography 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 | Holland, David M. Rosing-Asvid, Aqqalu Behrens, Jane W. Boje, Jesper Gladish, Carl Oceanic Boundary Conditions for Jakobshavn Glacier. Part I: Variability and Renewal of Ilulissat Icefjord Waters, 2001–14 |
| title | Oceanic Boundary Conditions for Jakobshavn Glacier. Part I: Variability and Renewal of Ilulissat Icefjord Waters, 2001–14 |
| title_full | Oceanic Boundary Conditions for Jakobshavn Glacier. Part I: Variability and Renewal of Ilulissat Icefjord Waters, 2001–14 |
| title_fullStr | Oceanic Boundary Conditions for Jakobshavn Glacier. Part I: Variability and Renewal of Ilulissat Icefjord Waters, 2001–14 |
| title_full_unstemmed | Oceanic Boundary Conditions for Jakobshavn Glacier. Part I: Variability and Renewal of Ilulissat Icefjord Waters, 2001–14 |
| title_short | Oceanic Boundary Conditions for Jakobshavn Glacier. Part I: Variability and Renewal of Ilulissat Icefjord Waters, 2001–14 |
| title_sort | oceanic boundary conditions for jakobshavn glacier part i variability and renewal of ilulissat icefjord waters 2001 14 |
| url | http://hdl.handle.net/1721.1/97579 https://orcid.org/0000-0002-3694-9942 |
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