St. Lawrence Island polynya: Ice circulation and dense water production
Dissertation (Ph.D.) University of Alaska Fairbanks, 1999 The St. Lawrence Island polynya (SLIP) opens every winter off the coast of St. Lawrence Island as winds move ice away from the shore. The SLIP is an important site for production of the dense water that flows northward through the Bering Stra...
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1999
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ftunivalaska:oai:scholarworks.alaska.edu:11122/9527 2023-06-11T04:09:08+02:00 St. Lawrence Island polynya: Ice circulation and dense water production Glueck, Mary Frances Milkovich Weingartner, Thomas J. 1999 http://hdl.handle.net/11122/9527 unknown http://hdl.handle.net/11122/9527 Physical oceanography Physics Atmospheric Science Polynyas Alaska Saint Lawrence Island Ice Sea ice Oceanography Sea ice drift Ocean temperature Ocean-atmosphere interaction Dissertation phd 1999 ftunivalaska 2023-05-11T17:54:52Z Dissertation (Ph.D.) University of Alaska Fairbanks, 1999 The St. Lawrence Island polynya (SLIP) opens every winter off the coast of St. Lawrence Island as winds move ice away from the shore. The SLIP is an important site for production of the dense water that flows northward through the Bering Strait to help maintain the Arctic Ocean halocline. Winter 1991/1992 ERS-1 SAR, thermal infrared, and passive microwave imagery are analyzed in combination with regional climate system and analytical simulations to investigate SLIP ice circulation, heat fluxes, and dense water production. Emphasis is on the February 1992 southern SLIP event. Satellite-based measurements show this polynya extended ~165km offshore and ~100km along shore at maximum extent. ERS-1 SAR GPS-derived ice motion indicated maximum ice speeds of ~30km day -1 during polynya expansion. Ice along the polynya boundary drifted parallel to the wind at 3--4% of the wind speed during north/northeasterly winds >7m s-1 Heat fluxes associated with the SLIP varied depending on method of calculation, but indicated increasing trends during polynya development. Associated ice production rates of 4.218.9cm day-1 were computed via different models. Dense water production, derived from ice production rates and polynya size, ranged from 0.011--0.017Sv, suggesting that the SLIP could account for 19--27% of the Bering Sea's contribution and 1--2% of the total Arctic contribution to Arctic Ocean halocline maintenance. Although the regional climate system model generated the SLIP on the same time scales as observed, a larger polynya resulted. The simulated polynya's heat and moisture impact was observed to at least 800mb, reaching 50km downstream. During periods of sustained winds, ice circulation was similar to that observed. Incorporation of a "barotropic" ocean component suggested that ocean circulation may be an important ice circulation forcing mechanism at the SLIP, especially during periods of weak winds, as inclusion greatly improved the simulated ice ... Doctoral or Postdoctoral Thesis Arctic Arctic Ocean Bering Strait Sea ice St Lawrence Island Alaska University of Alaska: ScholarWorks@UA Arctic Arctic Ocean Fairbanks Bering Strait Lawrence Island ENVELOPE(-103.718,-103.718,56.967,56.967) |
institution |
Open Polar |
collection |
University of Alaska: ScholarWorks@UA |
op_collection_id |
ftunivalaska |
language |
unknown |
topic |
Physical oceanography Physics Atmospheric Science Polynyas Alaska Saint Lawrence Island Ice Sea ice Oceanography Sea ice drift Ocean temperature Ocean-atmosphere interaction |
spellingShingle |
Physical oceanography Physics Atmospheric Science Polynyas Alaska Saint Lawrence Island Ice Sea ice Oceanography Sea ice drift Ocean temperature Ocean-atmosphere interaction Glueck, Mary Frances Milkovich St. Lawrence Island polynya: Ice circulation and dense water production |
topic_facet |
Physical oceanography Physics Atmospheric Science Polynyas Alaska Saint Lawrence Island Ice Sea ice Oceanography Sea ice drift Ocean temperature Ocean-atmosphere interaction |
description |
Dissertation (Ph.D.) University of Alaska Fairbanks, 1999 The St. Lawrence Island polynya (SLIP) opens every winter off the coast of St. Lawrence Island as winds move ice away from the shore. The SLIP is an important site for production of the dense water that flows northward through the Bering Strait to help maintain the Arctic Ocean halocline. Winter 1991/1992 ERS-1 SAR, thermal infrared, and passive microwave imagery are analyzed in combination with regional climate system and analytical simulations to investigate SLIP ice circulation, heat fluxes, and dense water production. Emphasis is on the February 1992 southern SLIP event. Satellite-based measurements show this polynya extended ~165km offshore and ~100km along shore at maximum extent. ERS-1 SAR GPS-derived ice motion indicated maximum ice speeds of ~30km day -1 during polynya expansion. Ice along the polynya boundary drifted parallel to the wind at 3--4% of the wind speed during north/northeasterly winds >7m s-1 Heat fluxes associated with the SLIP varied depending on method of calculation, but indicated increasing trends during polynya development. Associated ice production rates of 4.218.9cm day-1 were computed via different models. Dense water production, derived from ice production rates and polynya size, ranged from 0.011--0.017Sv, suggesting that the SLIP could account for 19--27% of the Bering Sea's contribution and 1--2% of the total Arctic contribution to Arctic Ocean halocline maintenance. Although the regional climate system model generated the SLIP on the same time scales as observed, a larger polynya resulted. The simulated polynya's heat and moisture impact was observed to at least 800mb, reaching 50km downstream. During periods of sustained winds, ice circulation was similar to that observed. Incorporation of a "barotropic" ocean component suggested that ocean circulation may be an important ice circulation forcing mechanism at the SLIP, especially during periods of weak winds, as inclusion greatly improved the simulated ice ... |
author2 |
Weingartner, Thomas J. |
format |
Doctoral or Postdoctoral Thesis |
author |
Glueck, Mary Frances Milkovich |
author_facet |
Glueck, Mary Frances Milkovich |
author_sort |
Glueck, Mary Frances Milkovich |
title |
St. Lawrence Island polynya: Ice circulation and dense water production |
title_short |
St. Lawrence Island polynya: Ice circulation and dense water production |
title_full |
St. Lawrence Island polynya: Ice circulation and dense water production |
title_fullStr |
St. Lawrence Island polynya: Ice circulation and dense water production |
title_full_unstemmed |
St. Lawrence Island polynya: Ice circulation and dense water production |
title_sort |
st. lawrence island polynya: ice circulation and dense water production |
publishDate |
1999 |
url |
http://hdl.handle.net/11122/9527 |
long_lat |
ENVELOPE(-103.718,-103.718,56.967,56.967) |
geographic |
Arctic Arctic Ocean Fairbanks Bering Strait Lawrence Island |
geographic_facet |
Arctic Arctic Ocean Fairbanks Bering Strait Lawrence Island |
genre |
Arctic Arctic Ocean Bering Strait Sea ice St Lawrence Island Alaska |
genre_facet |
Arctic Arctic Ocean Bering Strait Sea ice St Lawrence Island Alaska |
op_relation |
http://hdl.handle.net/11122/9527 |
_version_ |
1768382872398331904 |