Physical Controls on Ice Variability in the Bering Sea /
This study primarily focuses on sea ice variability in the Bering Sea, and its thermodynamic and dynamic controls. First, the seasonal cycle of sea ice variability in the Bering Sea is studied using a global fine-resolution (1/10 -degree) fully-coupled ocean and sea ice model forced with reanalysis...
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ftcdlib:qt75m1g99w 2023-05-15T15:43:16+02:00 Physical Controls on Ice Variability in the Bering Sea / Li, Linghan 1 PDF (1 online resource xiii, 148 pages) 2013-01-01 application/pdf http://www.escholarship.org/uc/item/75m1g99w http://n2t.net/ark:/20775/bb27660076 unknown eScholarship, University of California http://www.escholarship.org/uc/item/75m1g99w qt75m1g99w http://n2t.net/ark:/20775/bb27660076 public Li, Linghan. (2013). Physical Controls on Ice Variability in the Bering Sea /. UC San Diego: Retrieved from: http://www.escholarship.org/uc/item/75m1g99w UCSD Oceanography. (Discipline) Dissertations Academic dissertation 2013 ftcdlib 2016-04-02T19:04:53Z This study primarily focuses on sea ice variability in the Bering Sea, and its thermodynamic and dynamic controls. First, the seasonal cycle of sea ice variability in the Bering Sea is studied using a global fine-resolution (1/10 -degree) fully-coupled ocean and sea ice model forced with reanalysis atmospheric forcing for 1980-1989. The ocean/ sea-ice model consists of the Los Alamos National Laboratory Parallel Ocean Program (POP) and the Los Alamos Sea Ice Model (CICE). The modeled seasonal mean sea ice concentration strongly resembles satellite-derived observations. During winter, which dominates the annual mean, model sea ice is mainly formed in the northern Bering Sea, with the maximum ice growth rate occurring along the coast, due to cold air from northerly winds and ice motion away from the coast. South of St. Lawrence Island, winds drive sea ice to drift southwestward from the north to the southwestern ice covered region. Along the ice edge in the western Bering, ice is melted by warm ocean water, which is carried by the Bering Slope Current flowing to the northwest, resulting in the S-shaped asymmetric pattern seen in the ice edge. Second, the year- to-year variability of sea ice in the Bering Sea for 1980- 1989 is addressed. While thermodynamic processes dominate the variations in ice volume change in the Bering Sea on the large scale, dynamic processes are important locally near ice margins (both oceanic and land), where local dynamic and thermodynamic ice volume changes have opposite signs with large and similar amplitudes. The thermodynamic ice volume change is dominated by ice-air surface heat flux, which in turn is dominated by sensible heat flux, except near the southern ice edge where it is largely controlled by ocean-ice heat flux. This indicates that surface air temperature, which is specified from observations, strongly controls the ice volume tendency. Ice motion is generally consistent with winds driving the flow, except near certain straits in the north where ice motion largely follows ocean currents. This study also addresses Greenland supraglacial lakes on top of ice and ice-dammed lakes adjacent to glaciers. Those surface lakes have been observed to fill and drain periodically, affecting the ice motion over land. This study provides observational constraints on the volume of water contained in and drained from the lakes, based on the repeat laser altimetry Doctoral or Postdoctoral Thesis Bering Sea Greenland Sea ice St Lawrence Island University of California: eScholarship Bering Sea Greenland Lawrence Island ENVELOPE(-103.718,-103.718,56.967,56.967) |
institution |
Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
unknown |
topic |
UCSD Oceanography. (Discipline) Dissertations Academic |
spellingShingle |
UCSD Oceanography. (Discipline) Dissertations Academic Li, Linghan Physical Controls on Ice Variability in the Bering Sea / |
topic_facet |
UCSD Oceanography. (Discipline) Dissertations Academic |
description |
This study primarily focuses on sea ice variability in the Bering Sea, and its thermodynamic and dynamic controls. First, the seasonal cycle of sea ice variability in the Bering Sea is studied using a global fine-resolution (1/10 -degree) fully-coupled ocean and sea ice model forced with reanalysis atmospheric forcing for 1980-1989. The ocean/ sea-ice model consists of the Los Alamos National Laboratory Parallel Ocean Program (POP) and the Los Alamos Sea Ice Model (CICE). The modeled seasonal mean sea ice concentration strongly resembles satellite-derived observations. During winter, which dominates the annual mean, model sea ice is mainly formed in the northern Bering Sea, with the maximum ice growth rate occurring along the coast, due to cold air from northerly winds and ice motion away from the coast. South of St. Lawrence Island, winds drive sea ice to drift southwestward from the north to the southwestern ice covered region. Along the ice edge in the western Bering, ice is melted by warm ocean water, which is carried by the Bering Slope Current flowing to the northwest, resulting in the S-shaped asymmetric pattern seen in the ice edge. Second, the year- to-year variability of sea ice in the Bering Sea for 1980- 1989 is addressed. While thermodynamic processes dominate the variations in ice volume change in the Bering Sea on the large scale, dynamic processes are important locally near ice margins (both oceanic and land), where local dynamic and thermodynamic ice volume changes have opposite signs with large and similar amplitudes. The thermodynamic ice volume change is dominated by ice-air surface heat flux, which in turn is dominated by sensible heat flux, except near the southern ice edge where it is largely controlled by ocean-ice heat flux. This indicates that surface air temperature, which is specified from observations, strongly controls the ice volume tendency. Ice motion is generally consistent with winds driving the flow, except near certain straits in the north where ice motion largely follows ocean currents. This study also addresses Greenland supraglacial lakes on top of ice and ice-dammed lakes adjacent to glaciers. Those surface lakes have been observed to fill and drain periodically, affecting the ice motion over land. This study provides observational constraints on the volume of water contained in and drained from the lakes, based on the repeat laser altimetry |
format |
Doctoral or Postdoctoral Thesis |
author |
Li, Linghan |
author_facet |
Li, Linghan |
author_sort |
Li, Linghan |
title |
Physical Controls on Ice Variability in the Bering Sea / |
title_short |
Physical Controls on Ice Variability in the Bering Sea / |
title_full |
Physical Controls on Ice Variability in the Bering Sea / |
title_fullStr |
Physical Controls on Ice Variability in the Bering Sea / |
title_full_unstemmed |
Physical Controls on Ice Variability in the Bering Sea / |
title_sort |
physical controls on ice variability in the bering sea / |
publisher |
eScholarship, University of California |
publishDate |
2013 |
url |
http://www.escholarship.org/uc/item/75m1g99w http://n2t.net/ark:/20775/bb27660076 |
op_coverage |
1 PDF (1 online resource xiii, 148 pages) |
long_lat |
ENVELOPE(-103.718,-103.718,56.967,56.967) |
geographic |
Bering Sea Greenland Lawrence Island |
geographic_facet |
Bering Sea Greenland Lawrence Island |
genre |
Bering Sea Greenland Sea ice St Lawrence Island |
genre_facet |
Bering Sea Greenland Sea ice St Lawrence Island |
op_source |
Li, Linghan. (2013). Physical Controls on Ice Variability in the Bering Sea /. UC San Diego: Retrieved from: http://www.escholarship.org/uc/item/75m1g99w |
op_relation |
http://www.escholarship.org/uc/item/75m1g99w qt75m1g99w http://n2t.net/ark:/20775/bb27660076 |
op_rights |
public |
_version_ |
1766377325447872512 |