The transferability of adjoint inversion products between different ice flow models
Among the most important challenges faced by ice flow models is how to represent basal and rheological conditions, which are challenging to obtain from direct observations. A common practice is to use numerical inversions to calculate estimates for the unknown properties, but there are many possible...
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ftcopernicus:oai:publications.copernicus.org:tcd88574 2023-05-15T13:24:06+02:00 The transferability of adjoint inversion products between different ice flow models Barnes, Jowan M. Santos, Thiago Dias Goldberg, Daniel Gudmundsson, G. Hilmar Morlighem, Mathieu Rydt, Jan 2020-09-21 application/pdf https://doi.org/10.5194/tc-2020-235 https://tc.copernicus.org/preprints/tc-2020-235/ eng eng doi:10.5194/tc-2020-235 https://tc.copernicus.org/preprints/tc-2020-235/ eISSN: 1994-0424 Text 2020 ftcopernicus https://doi.org/10.5194/tc-2020-235 2020-09-28T16:22:13Z Among the most important challenges faced by ice flow models is how to represent basal and rheological conditions, which are challenging to obtain from direct observations. A common practice is to use numerical inversions to calculate estimates for the unknown properties, but there are many possible methods and not one standardised approach. As such, every ice flow model has a unique initialisation procedure. Here we compare the outputs of inversions from three different ice flow models, each employing a variant of adjoint-based optimisation to calculate basal sliding coefficients and flow rate factors using the same observed surface velocities and ice thickness distribution. The region we focus on is the Amundsen Sea Embayment in West Antarctica, the subject of much investigation due to rapid changes in the area over recent decades. We find that our inversions produce similar distributions of basal sliding across all models, despite using different techniques, implying that the methods used are highly robust and represent the physics without much influence by individual model behaviours. Transferring the products of inversions between models results in time-dependent simulations displaying variability on the order of or lower than existing model intercomparisons and process studies. While the successful transfer of inversion outputs from one model to another requires some extra effort and technical knowledge of the particular models involved, it is certainly possible and could indeed be useful for future intercomparison projects. Text Amundsen Sea Antarc* Antarctica West Antarctica Copernicus Publications: E-Journals Amundsen Sea West Antarctica |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
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English |
description |
Among the most important challenges faced by ice flow models is how to represent basal and rheological conditions, which are challenging to obtain from direct observations. A common practice is to use numerical inversions to calculate estimates for the unknown properties, but there are many possible methods and not one standardised approach. As such, every ice flow model has a unique initialisation procedure. Here we compare the outputs of inversions from three different ice flow models, each employing a variant of adjoint-based optimisation to calculate basal sliding coefficients and flow rate factors using the same observed surface velocities and ice thickness distribution. The region we focus on is the Amundsen Sea Embayment in West Antarctica, the subject of much investigation due to rapid changes in the area over recent decades. We find that our inversions produce similar distributions of basal sliding across all models, despite using different techniques, implying that the methods used are highly robust and represent the physics without much influence by individual model behaviours. Transferring the products of inversions between models results in time-dependent simulations displaying variability on the order of or lower than existing model intercomparisons and process studies. While the successful transfer of inversion outputs from one model to another requires some extra effort and technical knowledge of the particular models involved, it is certainly possible and could indeed be useful for future intercomparison projects. |
format |
Text |
author |
Barnes, Jowan M. Santos, Thiago Dias Goldberg, Daniel Gudmundsson, G. Hilmar Morlighem, Mathieu Rydt, Jan |
spellingShingle |
Barnes, Jowan M. Santos, Thiago Dias Goldberg, Daniel Gudmundsson, G. Hilmar Morlighem, Mathieu Rydt, Jan The transferability of adjoint inversion products between different ice flow models |
author_facet |
Barnes, Jowan M. Santos, Thiago Dias Goldberg, Daniel Gudmundsson, G. Hilmar Morlighem, Mathieu Rydt, Jan |
author_sort |
Barnes, Jowan M. |
title |
The transferability of adjoint inversion products between different ice flow models |
title_short |
The transferability of adjoint inversion products between different ice flow models |
title_full |
The transferability of adjoint inversion products between different ice flow models |
title_fullStr |
The transferability of adjoint inversion products between different ice flow models |
title_full_unstemmed |
The transferability of adjoint inversion products between different ice flow models |
title_sort |
transferability of adjoint inversion products between different ice flow models |
publishDate |
2020 |
url |
https://doi.org/10.5194/tc-2020-235 https://tc.copernicus.org/preprints/tc-2020-235/ |
geographic |
Amundsen Sea West Antarctica |
geographic_facet |
Amundsen Sea West Antarctica |
genre |
Amundsen Sea Antarc* Antarctica West Antarctica |
genre_facet |
Amundsen Sea Antarc* Antarctica West Antarctica |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-2020-235 https://tc.copernicus.org/preprints/tc-2020-235/ |
op_doi |
https://doi.org/10.5194/tc-2020-235 |
_version_ |
1766377484474908672 |