The age of surface-exposed ice along the northern margin of the Greenland Ice Sheet
Each summer, surface melting of the margin of the Greenland Ice Sheet exposes a distinctive visible stratigraphy that is related to past variability in subaerial dust deposition across the accumulation zone and subsequent ice flow toward the margin. Here we map this surface stratigraphy along the no...
Published in: | Journal of Glaciology |
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Cambridge University Press
2020
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ftdoajarticles:oai:doaj.org/article:5544cfd255914d13a915138d18febefb 2023-05-15T16:24:26+02:00 The age of surface-exposed ice along the northern margin of the Greenland Ice Sheet Joseph A. MacGregor Mark A. Fahnestock William T. Colgan Nicolaj K. Larsen Kristian K. Kjeldsen Jeffrey M. Welker 2020-08-01T00:00:00Z https://doi.org/10.1017/jog.2020.62 https://doaj.org/article/5544cfd255914d13a915138d18febefb EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0022143020000623/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2020.62 0022-1430 1727-5652 https://doaj.org/article/5544cfd255914d13a915138d18febefb Journal of Glaciology, Vol 66, Pp 667-684 (2020) Ice and climate ice chronology/dating paleoclimate remote sensing Environmental sciences GE1-350 Meteorology. Climatology QC851-999 article 2020 ftdoajarticles https://doi.org/10.1017/jog.2020.62 2023-03-12T01:30:57Z Each summer, surface melting of the margin of the Greenland Ice Sheet exposes a distinctive visible stratigraphy that is related to past variability in subaerial dust deposition across the accumulation zone and subsequent ice flow toward the margin. Here we map this surface stratigraphy along the northern margin of the ice sheet using mosaicked Sentinel-2 multispectral satellite imagery from the end of the 2019 melt season and finer-resolution WorldView-2/3 imagery for smaller regions of interest. We trace three distinct transitions in apparent dust concentration and the top of a darker basal layer. The three dust transitions have been identified previously as representing late-Pleistocene climatic transitions, allowing us to develop a coarse margin chronostratigraphy for northern Greenland. Substantial folding of late-Pleistocene stratigraphy is observed but uncommon. The oldest conformal surface-exposed ice in northern Greenland is likely located adjacent to Warming Land and may be up to ~55 thousand years old. Basal ice is commonly exposed hundreds of metres from the ice margin and may indicate a widespread frozen basal thermal state. We conclude that the ice margin across northern Greenland offers multiple opportunities to recover paleoclimatically distinct ice relative to previously studied regions in southwestern Greenland. Article in Journal/Newspaper Greenland Ice Sheet Journal of Glaciology Directory of Open Access Journals: DOAJ Articles Greenland Warming Land ENVELOPE(-52.000,-52.000,81.617,81.617) Journal of Glaciology 66 258 667 684 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Ice and climate ice chronology/dating paleoclimate remote sensing Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
spellingShingle |
Ice and climate ice chronology/dating paleoclimate remote sensing Environmental sciences GE1-350 Meteorology. Climatology QC851-999 Joseph A. MacGregor Mark A. Fahnestock William T. Colgan Nicolaj K. Larsen Kristian K. Kjeldsen Jeffrey M. Welker The age of surface-exposed ice along the northern margin of the Greenland Ice Sheet |
topic_facet |
Ice and climate ice chronology/dating paleoclimate remote sensing Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
description |
Each summer, surface melting of the margin of the Greenland Ice Sheet exposes a distinctive visible stratigraphy that is related to past variability in subaerial dust deposition across the accumulation zone and subsequent ice flow toward the margin. Here we map this surface stratigraphy along the northern margin of the ice sheet using mosaicked Sentinel-2 multispectral satellite imagery from the end of the 2019 melt season and finer-resolution WorldView-2/3 imagery for smaller regions of interest. We trace three distinct transitions in apparent dust concentration and the top of a darker basal layer. The three dust transitions have been identified previously as representing late-Pleistocene climatic transitions, allowing us to develop a coarse margin chronostratigraphy for northern Greenland. Substantial folding of late-Pleistocene stratigraphy is observed but uncommon. The oldest conformal surface-exposed ice in northern Greenland is likely located adjacent to Warming Land and may be up to ~55 thousand years old. Basal ice is commonly exposed hundreds of metres from the ice margin and may indicate a widespread frozen basal thermal state. We conclude that the ice margin across northern Greenland offers multiple opportunities to recover paleoclimatically distinct ice relative to previously studied regions in southwestern Greenland. |
format |
Article in Journal/Newspaper |
author |
Joseph A. MacGregor Mark A. Fahnestock William T. Colgan Nicolaj K. Larsen Kristian K. Kjeldsen Jeffrey M. Welker |
author_facet |
Joseph A. MacGregor Mark A. Fahnestock William T. Colgan Nicolaj K. Larsen Kristian K. Kjeldsen Jeffrey M. Welker |
author_sort |
Joseph A. MacGregor |
title |
The age of surface-exposed ice along the northern margin of the Greenland Ice Sheet |
title_short |
The age of surface-exposed ice along the northern margin of the Greenland Ice Sheet |
title_full |
The age of surface-exposed ice along the northern margin of the Greenland Ice Sheet |
title_fullStr |
The age of surface-exposed ice along the northern margin of the Greenland Ice Sheet |
title_full_unstemmed |
The age of surface-exposed ice along the northern margin of the Greenland Ice Sheet |
title_sort |
age of surface-exposed ice along the northern margin of the greenland ice sheet |
publisher |
Cambridge University Press |
publishDate |
2020 |
url |
https://doi.org/10.1017/jog.2020.62 https://doaj.org/article/5544cfd255914d13a915138d18febefb |
long_lat |
ENVELOPE(-52.000,-52.000,81.617,81.617) |
geographic |
Greenland Warming Land |
geographic_facet |
Greenland Warming Land |
genre |
Greenland Ice Sheet Journal of Glaciology |
genre_facet |
Greenland Ice Sheet Journal of Glaciology |
op_source |
Journal of Glaciology, Vol 66, Pp 667-684 (2020) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0022143020000623/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2020.62 0022-1430 1727-5652 https://doaj.org/article/5544cfd255914d13a915138d18febefb |
op_doi |
https://doi.org/10.1017/jog.2020.62 |
container_title |
Journal of Glaciology |
container_volume |
66 |
container_issue |
258 |
container_start_page |
667 |
op_container_end_page |
684 |
_version_ |
1766012895335809024 |