Data assimilation using a hybrid ice flow model
Hybrid models, or depth-integrated flow models that include the effect of both longitudinal stresses and vertical shearing, are becoming more prevalent in dynamical ice modeling. Under a wide range of conditions they closely approximate the well-known First Order stress balance, yet are of computati...
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Language: | English |
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Copernicus Publications
2011
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Online Access: | https://doi.org/10.5194/tc-5-315-2011 http://www.the-cryosphere.net/5/315/2011/tc-5-315-2011.pdf https://doaj.org/article/a1959e5533d44108962e6395703b76ff |
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fttriple:oai:gotriple.eu:oai:doaj.org/article:a1959e5533d44108962e6395703b76ff 2023-05-15T18:32:20+02:00 Data assimilation using a hybrid ice flow model D. N. Goldberg O. V. Sergienko 2011-04-01 https://doi.org/10.5194/tc-5-315-2011 http://www.the-cryosphere.net/5/315/2011/tc-5-315-2011.pdf https://doaj.org/article/a1959e5533d44108962e6395703b76ff en eng Copernicus Publications doi:10.5194/tc-5-315-2011 1994-0416 1994-0424 http://www.the-cryosphere.net/5/315/2011/tc-5-315-2011.pdf https://doaj.org/article/a1959e5533d44108962e6395703b76ff undefined The Cryosphere, Vol 5, Iss 2, Pp 315-327 (2011) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2011 fttriple https://doi.org/10.5194/tc-5-315-2011 2023-01-22T17:50:52Z Hybrid models, or depth-integrated flow models that include the effect of both longitudinal stresses and vertical shearing, are becoming more prevalent in dynamical ice modeling. Under a wide range of conditions they closely approximate the well-known First Order stress balance, yet are of computationally lower dimension, and thus require less intensive resources. Concomitant with the development and use of these models is the need to perform inversions of observed data. Here, an inverse control method is extended to use a hybrid flow model as a forward model. We derive an adjoint of a hybrid model and use it for inversion of ice-stream basal traction from observed surface velocities. A novel aspect of the adjoint derivation is a retention of non-linearities in Glen's flow law. Experiments show that in some cases, including those nonlinearities is advantageous in minimization of the cost function, yielding a more efficient inversion procedure. Article in Journal/Newspaper The Cryosphere Unknown The Cryosphere 5 2 315 327 |
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English |
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geo envir D. N. Goldberg O. V. Sergienko Data assimilation using a hybrid ice flow model |
topic_facet |
geo envir |
description |
Hybrid models, or depth-integrated flow models that include the effect of both longitudinal stresses and vertical shearing, are becoming more prevalent in dynamical ice modeling. Under a wide range of conditions they closely approximate the well-known First Order stress balance, yet are of computationally lower dimension, and thus require less intensive resources. Concomitant with the development and use of these models is the need to perform inversions of observed data. Here, an inverse control method is extended to use a hybrid flow model as a forward model. We derive an adjoint of a hybrid model and use it for inversion of ice-stream basal traction from observed surface velocities. A novel aspect of the adjoint derivation is a retention of non-linearities in Glen's flow law. Experiments show that in some cases, including those nonlinearities is advantageous in minimization of the cost function, yielding a more efficient inversion procedure. |
format |
Article in Journal/Newspaper |
author |
D. N. Goldberg O. V. Sergienko |
author_facet |
D. N. Goldberg O. V. Sergienko |
author_sort |
D. N. Goldberg |
title |
Data assimilation using a hybrid ice flow model |
title_short |
Data assimilation using a hybrid ice flow model |
title_full |
Data assimilation using a hybrid ice flow model |
title_fullStr |
Data assimilation using a hybrid ice flow model |
title_full_unstemmed |
Data assimilation using a hybrid ice flow model |
title_sort |
data assimilation using a hybrid ice flow model |
publisher |
Copernicus Publications |
publishDate |
2011 |
url |
https://doi.org/10.5194/tc-5-315-2011 http://www.the-cryosphere.net/5/315/2011/tc-5-315-2011.pdf https://doaj.org/article/a1959e5533d44108962e6395703b76ff |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_source |
The Cryosphere, Vol 5, Iss 2, Pp 315-327 (2011) |
op_relation |
doi:10.5194/tc-5-315-2011 1994-0416 1994-0424 http://www.the-cryosphere.net/5/315/2011/tc-5-315-2011.pdf https://doaj.org/article/a1959e5533d44108962e6395703b76ff |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/tc-5-315-2011 |
container_title |
The Cryosphere |
container_volume |
5 |
container_issue |
2 |
container_start_page |
315 |
op_container_end_page |
327 |
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1766216447199019008 |