Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada
Uplands of the Canadian Arctic Islands supported Late Wisconsinan ice caps that developed two landscape zones reflecting basal thermal conditions regulated by long-sustained ice flow patterns. Central cold-based zones protected older glacial and preglacial landscapes while peripheral warm-based zone...
Published in: | Progress in Physical Geography: Earth and Environment |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
SAGE Publications
1993
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1177/030913339301700208 http://journals.sagepub.com/doi/pdf/10.1177/030913339301700208 |
id |
crsagepubl:10.1177/030913339301700208 |
---|---|
record_format |
openpolar |
spelling |
crsagepubl:10.1177/030913339301700208 2024-06-23T07:50:00+00:00 Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada Dyke, Arthur S. 1993 http://dx.doi.org/10.1177/030913339301700208 http://journals.sagepub.com/doi/pdf/10.1177/030913339301700208 en eng SAGE Publications http://journals.sagepub.com/page/policies/text-and-data-mining-license Progress in Physical Geography: Earth and Environment volume 17, issue 2, page 223-247 ISSN 0309-1333 1477-0296 journal-article 1993 crsagepubl https://doi.org/10.1177/030913339301700208 2024-06-11T04:31:03Z Uplands of the Canadian Arctic Islands supported Late Wisconsinan ice caps that developed two landscape zones reflecting basal thermal conditions regulated by long-sustained ice flow patterns. Central cold-based zones protected older glacial and preglacial landscapes while peripheral warm-based zones scoured and otherwise altered their beds. Some geomorphic effects are independent of ice cap scale, others vary with scale. For ice caps of 30 km radius or more, scour-zone width remains proportionally constant to flowline length under similar flow conditions. But intensity of scouring, ice moulding of drift and rock eminences, size and abundance of subglacial meltwater features, and development of end moraines increase with ice cap size. Ice caps became entirely cold based early in retreat as the boundary between warm and cold ice shifted outward, probably because ice thinned and flow slackened. The frozen margins deflected meltwater, thus maximizing formation of lateral meltwater channels throughout retreat. The landform record of cold-based glaciers in this region is easily interpreted. Hence, regional ice sheet models invoking or based on the premise that cold-based ice leaves no geomorphic record seem untenable. Article in Journal/Newspaper Arctic glacier* Ice cap Ice Sheet SAGE Publications Arctic Canada Progress in Physical Geography: Earth and Environment 17 2 223 247 |
institution |
Open Polar |
collection |
SAGE Publications |
op_collection_id |
crsagepubl |
language |
English |
description |
Uplands of the Canadian Arctic Islands supported Late Wisconsinan ice caps that developed two landscape zones reflecting basal thermal conditions regulated by long-sustained ice flow patterns. Central cold-based zones protected older glacial and preglacial landscapes while peripheral warm-based zones scoured and otherwise altered their beds. Some geomorphic effects are independent of ice cap scale, others vary with scale. For ice caps of 30 km radius or more, scour-zone width remains proportionally constant to flowline length under similar flow conditions. But intensity of scouring, ice moulding of drift and rock eminences, size and abundance of subglacial meltwater features, and development of end moraines increase with ice cap size. Ice caps became entirely cold based early in retreat as the boundary between warm and cold ice shifted outward, probably because ice thinned and flow slackened. The frozen margins deflected meltwater, thus maximizing formation of lateral meltwater channels throughout retreat. The landform record of cold-based glaciers in this region is easily interpreted. Hence, regional ice sheet models invoking or based on the premise that cold-based ice leaves no geomorphic record seem untenable. |
format |
Article in Journal/Newspaper |
author |
Dyke, Arthur S. |
spellingShingle |
Dyke, Arthur S. Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada |
author_facet |
Dyke, Arthur S. |
author_sort |
Dyke, Arthur S. |
title |
Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada |
title_short |
Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada |
title_full |
Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada |
title_fullStr |
Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada |
title_full_unstemmed |
Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada |
title_sort |
landscapes of cold-centred late wisconsinan ice caps, arctic canada |
publisher |
SAGE Publications |
publishDate |
1993 |
url |
http://dx.doi.org/10.1177/030913339301700208 http://journals.sagepub.com/doi/pdf/10.1177/030913339301700208 |
geographic |
Arctic Canada |
geographic_facet |
Arctic Canada |
genre |
Arctic glacier* Ice cap Ice Sheet |
genre_facet |
Arctic glacier* Ice cap Ice Sheet |
op_source |
Progress in Physical Geography: Earth and Environment volume 17, issue 2, page 223-247 ISSN 0309-1333 1477-0296 |
op_rights |
http://journals.sagepub.com/page/policies/text-and-data-mining-license |
op_doi |
https://doi.org/10.1177/030913339301700208 |
container_title |
Progress in Physical Geography: Earth and Environment |
container_volume |
17 |
container_issue |
2 |
container_start_page |
223 |
op_container_end_page |
247 |
_version_ |
1802640734565695488 |