An iterative inverse method to estimate basal topography and initialize ice flow models
We evaluate an inverse approach to reconstruct distributed bedrock topography and simultaneously initialize an ice flow model. The inverse method involves an iterative procedure in which an ice dynamical model (PISM) is run multiple times over a prescribed period, while being forced with space-and t...
Published in: | The Cryosphere |
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Language: | English |
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Uppsala universitet, Luft-, vatten- och landskapslära
2013
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Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-205409 https://doi.org/10.5194/tc-7-987-2013 |
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ftuppsalauniv:oai:DiVA.org:uu-205409 2023-05-15T18:29:49+02:00 An iterative inverse method to estimate basal topography and initialize ice flow models van Pelt, W. J. J. Oerlemans, J. Reijmer, C. H. Pettersson, Rikard Pohjola, Veijo A. Isaksson, E. Divine, D. 2013 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-205409 https://doi.org/10.5194/tc-7-987-2013 eng eng Uppsala universitet, Luft-, vatten- och landskapslära The Cryosphere, 1994-0416, 2013, 7:3, s. 987-1006 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-205409 doi:10.5194/tc-7-987-2013 ISI:000321144100018 info:eu-repo/semantics/openAccess Natural Sciences Naturvetenskap Article in journal info:eu-repo/semantics/article text 2013 ftuppsalauniv https://doi.org/10.5194/tc-7-987-2013 2023-02-23T21:52:07Z We evaluate an inverse approach to reconstruct distributed bedrock topography and simultaneously initialize an ice flow model. The inverse method involves an iterative procedure in which an ice dynamical model (PISM) is run multiple times over a prescribed period, while being forced with space-and time-dependent climate input. After every iteration bed heights are adjusted using information of the remaining misfit between observed and modeled surface topography. The inverse method is first applied in synthetic experiments with a constant climate forcing to verify convergence and robustness of the approach in three dimensions. In a next step, the inverse approach is applied to Nordenskioldbreen, Svalbard, forced with height-and time-dependent climate input since 1300 AD. An L-curve stopping criterion is used to prevent overfitting. Validation against radar data reveals a high correlation (up to R = 0.89) between modeled and observed thicknesses. Remaining uncertainties can mainly be ascribed to inaccurate model physics, in particular, uncertainty in the description of sliding. Results demonstrate the applicability of this inverse method to reconstruct the ice thickness distribution of glaciers and ice caps. In addition to reconstructing bedrock topography, the method provides a direct tool to initialize ice flow models for forecasting experiments. Article in Journal/Newspaper Svalbard The Cryosphere Uppsala University: Publications (DiVA) Svalbard The Cryosphere 7 3 987 1006 |
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Open Polar |
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Uppsala University: Publications (DiVA) |
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ftuppsalauniv |
language |
English |
topic |
Natural Sciences Naturvetenskap |
spellingShingle |
Natural Sciences Naturvetenskap van Pelt, W. J. J. Oerlemans, J. Reijmer, C. H. Pettersson, Rikard Pohjola, Veijo A. Isaksson, E. Divine, D. An iterative inverse method to estimate basal topography and initialize ice flow models |
topic_facet |
Natural Sciences Naturvetenskap |
description |
We evaluate an inverse approach to reconstruct distributed bedrock topography and simultaneously initialize an ice flow model. The inverse method involves an iterative procedure in which an ice dynamical model (PISM) is run multiple times over a prescribed period, while being forced with space-and time-dependent climate input. After every iteration bed heights are adjusted using information of the remaining misfit between observed and modeled surface topography. The inverse method is first applied in synthetic experiments with a constant climate forcing to verify convergence and robustness of the approach in three dimensions. In a next step, the inverse approach is applied to Nordenskioldbreen, Svalbard, forced with height-and time-dependent climate input since 1300 AD. An L-curve stopping criterion is used to prevent overfitting. Validation against radar data reveals a high correlation (up to R = 0.89) between modeled and observed thicknesses. Remaining uncertainties can mainly be ascribed to inaccurate model physics, in particular, uncertainty in the description of sliding. Results demonstrate the applicability of this inverse method to reconstruct the ice thickness distribution of glaciers and ice caps. In addition to reconstructing bedrock topography, the method provides a direct tool to initialize ice flow models for forecasting experiments. |
format |
Article in Journal/Newspaper |
author |
van Pelt, W. J. J. Oerlemans, J. Reijmer, C. H. Pettersson, Rikard Pohjola, Veijo A. Isaksson, E. Divine, D. |
author_facet |
van Pelt, W. J. J. Oerlemans, J. Reijmer, C. H. Pettersson, Rikard Pohjola, Veijo A. Isaksson, E. Divine, D. |
author_sort |
van Pelt, W. J. J. |
title |
An iterative inverse method to estimate basal topography and initialize ice flow models |
title_short |
An iterative inverse method to estimate basal topography and initialize ice flow models |
title_full |
An iterative inverse method to estimate basal topography and initialize ice flow models |
title_fullStr |
An iterative inverse method to estimate basal topography and initialize ice flow models |
title_full_unstemmed |
An iterative inverse method to estimate basal topography and initialize ice flow models |
title_sort |
iterative inverse method to estimate basal topography and initialize ice flow models |
publisher |
Uppsala universitet, Luft-, vatten- och landskapslära |
publishDate |
2013 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-205409 https://doi.org/10.5194/tc-7-987-2013 |
geographic |
Svalbard |
geographic_facet |
Svalbard |
genre |
Svalbard The Cryosphere |
genre_facet |
Svalbard The Cryosphere |
op_relation |
The Cryosphere, 1994-0416, 2013, 7:3, s. 987-1006 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-205409 doi:10.5194/tc-7-987-2013 ISI:000321144100018 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/tc-7-987-2013 |
container_title |
The Cryosphere |
container_volume |
7 |
container_issue |
3 |
container_start_page |
987 |
op_container_end_page |
1006 |
_version_ |
1766213220633149440 |