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...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2013
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-7-987-2013 https://noa.gwlb.de/receive/cop_mods_00022512 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00022467/tc-7-987-2013.pdf https://tc.copernicus.org/articles/7/987/2013/tc-7-987-2013.pdf |
id |
ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00022512 |
---|---|
record_format |
openpolar |
spelling |
ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00022512 2023-05-15T18:29:48+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, R. Pohjola, V. A. Isaksson, E. Divine, D. 2013-06 electronic https://doi.org/10.5194/tc-7-987-2013 https://noa.gwlb.de/receive/cop_mods_00022512 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00022467/tc-7-987-2013.pdf https://tc.copernicus.org/articles/7/987/2013/tc-7-987-2013.pdf eng eng Copernicus Publications The Cryosphere -- ˜Theœ Cryosphere -- http://www.bibliothek.uni-regensburg.de/ezeit/?2393169 -- http://www.the-cryosphere.net/ -- 1994-0424 https://doi.org/10.5194/tc-7-987-2013 https://noa.gwlb.de/receive/cop_mods_00022512 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00022467/tc-7-987-2013.pdf https://tc.copernicus.org/articles/7/987/2013/tc-7-987-2013.pdf uneingeschränkt info:eu-repo/semantics/openAccess article Verlagsveröffentlichung article Text doc-type:article 2013 ftnonlinearchiv https://doi.org/10.5194/tc-7-987-2013 2022-02-08T22:51:04Z 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 Nordenskiöldbreen, 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 Niedersächsisches Online-Archiv NOA Nordenskiöldbreen ENVELOPE(17.166,17.166,78.676,78.676) Svalbard The Cryosphere 7 3 987 1006 |
institution |
Open Polar |
collection |
Niedersächsisches Online-Archiv NOA |
op_collection_id |
ftnonlinearchiv |
language |
English |
topic |
article Verlagsveröffentlichung |
spellingShingle |
article Verlagsveröffentlichung van Pelt, W. J. J. Oerlemans, J. Reijmer, C. H. Pettersson, R. Pohjola, V. A. Isaksson, E. Divine, D. An iterative inverse method to estimate basal topography and initialize ice flow models |
topic_facet |
article Verlagsveröffentlichung |
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 Nordenskiöldbreen, 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, R. Pohjola, V. A. Isaksson, E. Divine, D. |
author_facet |
van Pelt, W. J. J. Oerlemans, J. Reijmer, C. H. Pettersson, R. Pohjola, V. 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 |
Copernicus Publications |
publishDate |
2013 |
url |
https://doi.org/10.5194/tc-7-987-2013 https://noa.gwlb.de/receive/cop_mods_00022512 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00022467/tc-7-987-2013.pdf https://tc.copernicus.org/articles/7/987/2013/tc-7-987-2013.pdf |
long_lat |
ENVELOPE(17.166,17.166,78.676,78.676) |
geographic |
Nordenskiöldbreen Svalbard |
geographic_facet |
Nordenskiöldbreen Svalbard |
genre |
Svalbard The Cryosphere |
genre_facet |
Svalbard The Cryosphere |
op_relation |
The Cryosphere -- ˜Theœ Cryosphere -- http://www.bibliothek.uni-regensburg.de/ezeit/?2393169 -- http://www.the-cryosphere.net/ -- 1994-0424 https://doi.org/10.5194/tc-7-987-2013 https://noa.gwlb.de/receive/cop_mods_00022512 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00022467/tc-7-987-2013.pdf https://tc.copernicus.org/articles/7/987/2013/tc-7-987-2013.pdf |
op_rights |
uneingeschränkt 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_ |
1766213201770315776 |