Initialization of ice-sheet forecasts viewed as an inverse Robin problem
As simulations of 21st-century climate start to include components with longer timescales, such as ice sheets, the initial conditions for those components will become critical to the forecast. This paper describes an algorithm for specifying the initial state of an ice-sheet model, given spatially c...
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Online Access: | https://nrl.northumbria.ac.uk/id/eprint/37476/ https://doi.org/10.3189/002214310792447699 |
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ftunivnorthumb:oai:nrl.northumbria.ac.uk:37476 2023-05-15T16:40:33+02:00 Initialization of ice-sheet forecasts viewed as an inverse Robin problem Arthern, Robert Gudmundsson, Hilmar 2010-08 https://nrl.northumbria.ac.uk/id/eprint/37476/ https://doi.org/10.3189/002214310792447699 unknown Cambridge University Press Arthern, Robert and Gudmundsson, Hilmar (2010) Initialization of ice-sheet forecasts viewed as an inverse Robin problem. Journal of Glaciology, 56 (197). pp. 527-533. ISSN 0022-1430 F800 Physical and Terrestrial Geographical and Environmental Sciences Article PeerReviewed 2010 ftunivnorthumb https://doi.org/10.3189/002214310792447699 2022-09-25T06:08:56Z As simulations of 21st-century climate start to include components with longer timescales, such as ice sheets, the initial conditions for those components will become critical to the forecast. This paper describes an algorithm for specifying the initial state of an ice-sheet model, given spatially continuous observations of the surface elevation, the velocity at the surface and the thickness of the ice. The algorithm can be viewed as an inverse procedure to solve for the viscosity or the basal drag coefficient. It applies to incompressible Stokes flow over an impenetrable boundary, and is based upon techniques used in electric impedance tomography; in particular, the minimization of a type of cost function proposed by Kohn and Vogelius. The algorithm can be implemented numerically using only the forward solution of the Stokes equations, with no need to develop a separate adjoint model. The only requirement placed upon the numerical Stokes solver is that boundary conditions of Dirichlet, Neumann and Robin types can be implemented. As an illustrative example, the algorithm is applied to shear flow down an impenetrable inclined plane. A fully three-dimensional test case using a commercially available solver for the Stokes equations is also presented. Article in Journal/Newspaper Ice Sheet Journal of Glaciology Northumbria University, Newcastle: Northumbria Research Link (NRL) Journal of Glaciology 56 197 527 533 |
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Open Polar |
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Northumbria University, Newcastle: Northumbria Research Link (NRL) |
op_collection_id |
ftunivnorthumb |
language |
unknown |
topic |
F800 Physical and Terrestrial Geographical and Environmental Sciences |
spellingShingle |
F800 Physical and Terrestrial Geographical and Environmental Sciences Arthern, Robert Gudmundsson, Hilmar Initialization of ice-sheet forecasts viewed as an inverse Robin problem |
topic_facet |
F800 Physical and Terrestrial Geographical and Environmental Sciences |
description |
As simulations of 21st-century climate start to include components with longer timescales, such as ice sheets, the initial conditions for those components will become critical to the forecast. This paper describes an algorithm for specifying the initial state of an ice-sheet model, given spatially continuous observations of the surface elevation, the velocity at the surface and the thickness of the ice. The algorithm can be viewed as an inverse procedure to solve for the viscosity or the basal drag coefficient. It applies to incompressible Stokes flow over an impenetrable boundary, and is based upon techniques used in electric impedance tomography; in particular, the minimization of a type of cost function proposed by Kohn and Vogelius. The algorithm can be implemented numerically using only the forward solution of the Stokes equations, with no need to develop a separate adjoint model. The only requirement placed upon the numerical Stokes solver is that boundary conditions of Dirichlet, Neumann and Robin types can be implemented. As an illustrative example, the algorithm is applied to shear flow down an impenetrable inclined plane. A fully three-dimensional test case using a commercially available solver for the Stokes equations is also presented. |
format |
Article in Journal/Newspaper |
author |
Arthern, Robert Gudmundsson, Hilmar |
author_facet |
Arthern, Robert Gudmundsson, Hilmar |
author_sort |
Arthern, Robert |
title |
Initialization of ice-sheet forecasts viewed as an inverse Robin problem |
title_short |
Initialization of ice-sheet forecasts viewed as an inverse Robin problem |
title_full |
Initialization of ice-sheet forecasts viewed as an inverse Robin problem |
title_fullStr |
Initialization of ice-sheet forecasts viewed as an inverse Robin problem |
title_full_unstemmed |
Initialization of ice-sheet forecasts viewed as an inverse Robin problem |
title_sort |
initialization of ice-sheet forecasts viewed as an inverse robin problem |
publisher |
Cambridge University Press |
publishDate |
2010 |
url |
https://nrl.northumbria.ac.uk/id/eprint/37476/ https://doi.org/10.3189/002214310792447699 |
genre |
Ice Sheet Journal of Glaciology |
genre_facet |
Ice Sheet Journal of Glaciology |
op_relation |
Arthern, Robert and Gudmundsson, Hilmar (2010) Initialization of ice-sheet forecasts viewed as an inverse Robin problem. Journal of Glaciology, 56 (197). pp. 527-533. ISSN 0022-1430 |
op_doi |
https://doi.org/10.3189/002214310792447699 |
container_title |
Journal of Glaciology |
container_volume |
56 |
container_issue |
197 |
container_start_page |
527 |
op_container_end_page |
533 |
_version_ |
1766030956971425792 |