Planimetric ice-flow convergence and flow-orthonormal strain rate across the Antarctic Ice Sheet, with links to model result files
Fast-flowing ice streams discharge most of the ice from the interior of the Antarctic Ice Sheet coastward. Understanding how their tributary organisation is governed and evolves is essential for developing reliable models of the ice sheet's response to climate change. Despite much research on i...
Main Author: | |
---|---|
Format: | Dataset |
Language: | English |
Published: |
PANGAEA
2015
|
Subjects: | |
Online Access: | https://doi.pangaea.de/10.1594/PANGAEA.841137 https://doi.org/10.1594/PANGAEA.841137 |
id |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.841137 |
---|---|
record_format |
openpolar |
spelling |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.841137 2023-05-15T14:03:04+02:00 Planimetric ice-flow convergence and flow-orthonormal strain rate across the Antarctic Ice Sheet, with links to model result files Ng, Felix S L LATITUDE: -90.000000 * LONGITUDE: 0.000000 2015-01-05 text/tab-separated-values, 40 data points https://doi.pangaea.de/10.1594/PANGAEA.841137 https://doi.org/10.1594/PANGAEA.841137 en eng PANGAEA Description of data files (URI: hdl:10013/epic.45941.d001) https://doi.pangaea.de/10.1594/PANGAEA.841137 https://doi.org/10.1594/PANGAEA.841137 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Ng, Felix S L (2015): Spatial complexity of ice flow across the Antarctic Ice Sheet. Nature Geoscience, 8(10), https://doi.org/10.1038/ngeo2532 File content File format File name File size pan-Antarctica Uniform resource locator/link to model result file Dataset 2015 ftpangaea https://doi.org/10.1594/PANGAEA.841137 https://doi.org/10.1038/ngeo2532 2023-01-20T09:04:57Z Fast-flowing ice streams discharge most of the ice from the interior of the Antarctic Ice Sheet coastward. Understanding how their tributary organisation is governed and evolves is essential for developing reliable models of the ice sheet's response to climate change. Despite much research on ice-stream mechanics, this problem is unsolved, because the complexity of flow within and across the tributary networks has hardly been interrogated. Here I present the first map of planimetric flow convergence across the ice sheet, calculated from satellite measurements of ice surface velocity, and use it to explore this complexity. The convergence map of Antarctica elucidates how ice-stream tributaries draw ice from the interior. It also reveals curvilinear zones of convergence along lateral shear margins of streaming, and abundant convergence ripples associated with nonlinear ice rheology and changes in bed topography and friction. Flow convergence on ice-stream tributaries and their feeding zones is markedly uneven, and interspersed with divergence at distances of the order of kilometres. For individual drainage basins as well as the ice sheet as a whole, the range of convergence and divergence decreases systematically with flow speed, implying that fast flow cannot converge or diverge as much as slow flow. I therefore deduce that flow in ice-stream networks is subject to mechanical regulation that limits flow-orthonormal strain rates. These properties and the gridded data of convergence and flow-orthonormal strain rate in this archive provide targets for ice- sheet simulations and motivate more research into the origin and dynamics of tributarization. Dataset Antarc* Antarctic Antarctica Ice Sheet PANGAEA - Data Publisher for Earth & Environmental Science Antarctic The Antarctic ENVELOPE(0.000000,0.000000,-90.000000,-90.000000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
File content File format File name File size pan-Antarctica Uniform resource locator/link to model result file |
spellingShingle |
File content File format File name File size pan-Antarctica Uniform resource locator/link to model result file Ng, Felix S L Planimetric ice-flow convergence and flow-orthonormal strain rate across the Antarctic Ice Sheet, with links to model result files |
topic_facet |
File content File format File name File size pan-Antarctica Uniform resource locator/link to model result file |
description |
Fast-flowing ice streams discharge most of the ice from the interior of the Antarctic Ice Sheet coastward. Understanding how their tributary organisation is governed and evolves is essential for developing reliable models of the ice sheet's response to climate change. Despite much research on ice-stream mechanics, this problem is unsolved, because the complexity of flow within and across the tributary networks has hardly been interrogated. Here I present the first map of planimetric flow convergence across the ice sheet, calculated from satellite measurements of ice surface velocity, and use it to explore this complexity. The convergence map of Antarctica elucidates how ice-stream tributaries draw ice from the interior. It also reveals curvilinear zones of convergence along lateral shear margins of streaming, and abundant convergence ripples associated with nonlinear ice rheology and changes in bed topography and friction. Flow convergence on ice-stream tributaries and their feeding zones is markedly uneven, and interspersed with divergence at distances of the order of kilometres. For individual drainage basins as well as the ice sheet as a whole, the range of convergence and divergence decreases systematically with flow speed, implying that fast flow cannot converge or diverge as much as slow flow. I therefore deduce that flow in ice-stream networks is subject to mechanical regulation that limits flow-orthonormal strain rates. These properties and the gridded data of convergence and flow-orthonormal strain rate in this archive provide targets for ice- sheet simulations and motivate more research into the origin and dynamics of tributarization. |
format |
Dataset |
author |
Ng, Felix S L |
author_facet |
Ng, Felix S L |
author_sort |
Ng, Felix S L |
title |
Planimetric ice-flow convergence and flow-orthonormal strain rate across the Antarctic Ice Sheet, with links to model result files |
title_short |
Planimetric ice-flow convergence and flow-orthonormal strain rate across the Antarctic Ice Sheet, with links to model result files |
title_full |
Planimetric ice-flow convergence and flow-orthonormal strain rate across the Antarctic Ice Sheet, with links to model result files |
title_fullStr |
Planimetric ice-flow convergence and flow-orthonormal strain rate across the Antarctic Ice Sheet, with links to model result files |
title_full_unstemmed |
Planimetric ice-flow convergence and flow-orthonormal strain rate across the Antarctic Ice Sheet, with links to model result files |
title_sort |
planimetric ice-flow convergence and flow-orthonormal strain rate across the antarctic ice sheet, with links to model result files |
publisher |
PANGAEA |
publishDate |
2015 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.841137 https://doi.org/10.1594/PANGAEA.841137 |
op_coverage |
LATITUDE: -90.000000 * LONGITUDE: 0.000000 |
long_lat |
ENVELOPE(0.000000,0.000000,-90.000000,-90.000000) |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Antarctica Ice Sheet |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet |
op_source |
Supplement to: Ng, Felix S L (2015): Spatial complexity of ice flow across the Antarctic Ice Sheet. Nature Geoscience, 8(10), https://doi.org/10.1038/ngeo2532 |
op_relation |
Description of data files (URI: hdl:10013/epic.45941.d001) https://doi.pangaea.de/10.1594/PANGAEA.841137 https://doi.org/10.1594/PANGAEA.841137 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/PANGAEA.841137 https://doi.org/10.1038/ngeo2532 |
_version_ |
1766273564053340160 |