Ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the Scandinavian Ice Sheet
High-resolution digital elevation models of Finland and Sweden based on LiDAR (Light Detection and Ranging) reveal subglacial landforms in great detail. We describe the ice-sheet scale distribution and morphometric characteristics of a glacial landform that is distinctive in morphology and occurs co...
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Cambridge University Press
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ftdoajarticles:oai:doaj.org/article:d7e1f5d96d50466ab46c10dd1a88ea0c 2023-05-15T13:29:35+02:00 Ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the Scandinavian Ice Sheet Antti E. K. Ojala Gustaf Peterson Joni Mäkinen Mark D. Johnson Kari Kajuutti Jukka-Pekka Palmu Elina Ahokangas Christian Öhrling 2019-12-01T00:00:00Z https://doi.org/10.1017/aog.2019.34 https://doaj.org/article/d7e1f5d96d50466ab46c10dd1a88ea0c EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S026030551900034X/type/journal_article https://doaj.org/toc/0260-3055 https://doaj.org/toc/1727-5644 doi:10.1017/aog.2019.34 0260-3055 1727-5644 https://doaj.org/article/d7e1f5d96d50466ab46c10dd1a88ea0c Annals of Glaciology, Vol 60, Pp 115-126 (2019) Geomorphology glacial geology glacier hydrology landform murtoo Meteorology. Climatology QC851-999 article 2019 ftdoajarticles https://doi.org/10.1017/aog.2019.34 2023-03-12T01:31:55Z High-resolution digital elevation models of Finland and Sweden based on LiDAR (Light Detection and Ranging) reveal subglacial landforms in great detail. We describe the ice-sheet scale distribution and morphometric characteristics of a glacial landform that is distinctive in morphology and occurs commonly in the central parts of the former Scandinavian Ice Sheet, especially up-ice of the Younger Dryas end moraine zone. We refer to these triangular or V-shaped landforms as murtoos (singular, ‘murtoo’). Murtoos are typically 30–200 m in length and 30–200 m in width with a relief of commonly <5 m. Murtoos have straight and steep edges, a triangular tip oriented parallel to ice-flow direction, and an asymmetric longitudinal profile with a shorter, but steeper down-ice slope. The spatial distribution of murtoos and their geomorphic relation to other landforms indicate that they formed subglacially during times of climate warming and rapid retreat of the Scandinavian Ice Sheet when large amounts of meltwater were delivered to the bed. Murtoos are formed under warm-based ice and may be associated with a non-channelized subglacial hydraulic system that evacuated large discharges of subglacial water. Article in Journal/Newspaper Annals of Glaciology Ice Sheet Directory of Open Access Journals: DOAJ Articles Annals of Glaciology 60 80 115 126 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Geomorphology glacial geology glacier hydrology landform murtoo Meteorology. Climatology QC851-999 |
spellingShingle |
Geomorphology glacial geology glacier hydrology landform murtoo Meteorology. Climatology QC851-999 Antti E. K. Ojala Gustaf Peterson Joni Mäkinen Mark D. Johnson Kari Kajuutti Jukka-Pekka Palmu Elina Ahokangas Christian Öhrling Ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the Scandinavian Ice Sheet |
topic_facet |
Geomorphology glacial geology glacier hydrology landform murtoo Meteorology. Climatology QC851-999 |
description |
High-resolution digital elevation models of Finland and Sweden based on LiDAR (Light Detection and Ranging) reveal subglacial landforms in great detail. We describe the ice-sheet scale distribution and morphometric characteristics of a glacial landform that is distinctive in morphology and occurs commonly in the central parts of the former Scandinavian Ice Sheet, especially up-ice of the Younger Dryas end moraine zone. We refer to these triangular or V-shaped landforms as murtoos (singular, ‘murtoo’). Murtoos are typically 30–200 m in length and 30–200 m in width with a relief of commonly <5 m. Murtoos have straight and steep edges, a triangular tip oriented parallel to ice-flow direction, and an asymmetric longitudinal profile with a shorter, but steeper down-ice slope. The spatial distribution of murtoos and their geomorphic relation to other landforms indicate that they formed subglacially during times of climate warming and rapid retreat of the Scandinavian Ice Sheet when large amounts of meltwater were delivered to the bed. Murtoos are formed under warm-based ice and may be associated with a non-channelized subglacial hydraulic system that evacuated large discharges of subglacial water. |
format |
Article in Journal/Newspaper |
author |
Antti E. K. Ojala Gustaf Peterson Joni Mäkinen Mark D. Johnson Kari Kajuutti Jukka-Pekka Palmu Elina Ahokangas Christian Öhrling |
author_facet |
Antti E. K. Ojala Gustaf Peterson Joni Mäkinen Mark D. Johnson Kari Kajuutti Jukka-Pekka Palmu Elina Ahokangas Christian Öhrling |
author_sort |
Antti E. K. Ojala |
title |
Ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the Scandinavian Ice Sheet |
title_short |
Ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the Scandinavian Ice Sheet |
title_full |
Ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the Scandinavian Ice Sheet |
title_fullStr |
Ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the Scandinavian Ice Sheet |
title_full_unstemmed |
Ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the Scandinavian Ice Sheet |
title_sort |
ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the scandinavian ice sheet |
publisher |
Cambridge University Press |
publishDate |
2019 |
url |
https://doi.org/10.1017/aog.2019.34 https://doaj.org/article/d7e1f5d96d50466ab46c10dd1a88ea0c |
genre |
Annals of Glaciology Ice Sheet |
genre_facet |
Annals of Glaciology Ice Sheet |
op_source |
Annals of Glaciology, Vol 60, Pp 115-126 (2019) |
op_relation |
https://www.cambridge.org/core/product/identifier/S026030551900034X/type/journal_article https://doaj.org/toc/0260-3055 https://doaj.org/toc/1727-5644 doi:10.1017/aog.2019.34 0260-3055 1727-5644 https://doaj.org/article/d7e1f5d96d50466ab46c10dd1a88ea0c |
op_doi |
https://doi.org/10.1017/aog.2019.34 |
container_title |
Annals of Glaciology |
container_volume |
60 |
container_issue |
80 |
container_start_page |
115 |
op_container_end_page |
126 |
_version_ |
1766001343835668480 |