subject:(shallow ice approximation)

Delft University of Technology

1. van Dongen, Eef (author). Coupling approximation levels for modeling ice flow on paleo time scales.

Degree: 2017, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:caed0f22-278b-4dc3-ac52-775a17706e3c

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Ice flow, forced by gravity is governed by the Full Stokes (FS) equations, which are computationally intensive to solve due to their non-linearity. Therefore, it… (more)

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Ice flow, forced by gravity is governed by the Full Stokes (FS) equations, which are computationally intensive to solve due to their non-linearity. Therefore, it has been unavoidable to approximate the FS equations when modeling growth and collapse of an ice sheet-shelf system, which requires simulating many thousands of years. However, the most popular Shallow Ice Approximation (SIA) and Shallow Shelf Approximation (SSA) are only accurate in certain parts of an ice sheet, both excluding the grounding line where the ice starts floating. Using the Finite Element software Elmer/Ice, SIA and SSA are dynamically coupled to FS aiming to maintain high precision and reduce computation time. An existing coupling of SIA and FS, called ISCAL [Ahlkrona et al., 2013a], is investigated for robustness. It is shown that instabilities in the FS solution limit ISCAL’s robustness. A novel way of iteratively coupling SSA and FS has been implemented into the open source Finite Element software Elmer/Ice and applied to both 2D and 3D conceptual marine ice sheets. The SSA-FS coupling shows to be very accurate, for both diagnostic and prognostic runs (error in velocity respectively below 0.5% and 5%). Grounding line dynamics of the SSA-FS coupling are similar to the FS model under a periodical forcing in a simulation covering 3000 years. The current implementation does not yield speed up in 2D due to inefficient assembly of the matrices to be solved. In 3D, the cpu time is reduced to two thirds of the cpu time of the FS model despite inefficient assembly. The total number of FS iterations in the SSA-FS coupling is comparable to the FS model, showing a large potential of reducing computation time since computation time of the SSA model is up to 3% of the FS model’s computation time when applied to the same ice shelf ramp. In future research, the SSA-FS coupling can be combined with ISCAL, but this requires both efficient implementation of the SSA-FS coupling and improved stabilization methods for FS.

Applied Mathematics

Advisors/Committee Members: van Gijzen, Martin (mentor), Delft University of Technology (degree granting institution).

Subjects/Keywords: Finite Element Method; Ice sheet modeling; coupling approximations; full stokes; shallow shelf approximation; shallow ice approximation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

van Dongen, E. (. (2017). Coupling approximation levels for modeling ice flow on paleo time scales. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:caed0f22-278b-4dc3-ac52-775a17706e3c

Chicago Manual of Style (16^th Edition):

van Dongen, Eef (author). “Coupling approximation levels for modeling ice flow on paleo time scales.” 2017. Masters Thesis, Delft University of Technology. Accessed January 26, 2021. http://resolver.tudelft.nl/uuid:caed0f22-278b-4dc3-ac52-775a17706e3c.

MLA Handbook (7^th Edition):

van Dongen, Eef (author). “Coupling approximation levels for modeling ice flow on paleo time scales.” 2017. Web. 26 Jan 2021.

Vancouver:

van Dongen E(. Coupling approximation levels for modeling ice flow on paleo time scales. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Jan 26]. Available from: http://resolver.tudelft.nl/uuid:caed0f22-278b-4dc3-ac52-775a17706e3c.

Council of Science Editors:

van Dongen E(. Coupling approximation levels for modeling ice flow on paleo time scales. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:caed0f22-278b-4dc3-ac52-775a17706e3c

University of Montana

2. Campbell, Joshua Charles. IMPLEMENTATION OF A VERTICALLY INTEGRATED ICE SHEET MOMENTUM BALANCE MODEL.

Degree: MS, 2013, University of Montana

URL: https://scholarworks.umt.edu/etd/552

► A new high-fidelity ice sheet momentum balance model meant for inclusion in the Glimmer community ice-sheet model is presented. As a component of the Community… (more)

Subjects/Keywords: approximation; discretization; finite elements; first variation; fortran; fortran 90; galerkin; ice sheet; incompressible; l1l2; model; momentum balance; non-newtonian; partial differential equations; rheology; sea-level rise; shallow ice; shallow shelf

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Campbell, J. C. (2013). IMPLEMENTATION OF A VERTICALLY INTEGRATED ICE SHEET MOMENTUM BALANCE MODEL. (Masters Thesis). University of Montana. Retrieved from https://scholarworks.umt.edu/etd/552

Chicago Manual of Style (16^th Edition):

Campbell, Joshua Charles. “IMPLEMENTATION OF A VERTICALLY INTEGRATED ICE SHEET MOMENTUM BALANCE MODEL.” 2013. Masters Thesis, University of Montana. Accessed January 26, 2021. https://scholarworks.umt.edu/etd/552.

MLA Handbook (7^th Edition):

Campbell, Joshua Charles. “IMPLEMENTATION OF A VERTICALLY INTEGRATED ICE SHEET MOMENTUM BALANCE MODEL.” 2013. Web. 26 Jan 2021.

Vancouver:

Campbell JC. IMPLEMENTATION OF A VERTICALLY INTEGRATED ICE SHEET MOMENTUM BALANCE MODEL. [Internet] [Masters thesis]. University of Montana; 2013. [cited 2021 Jan 26]. Available from: https://scholarworks.umt.edu/etd/552.

Council of Science Editors:

Campbell JC. IMPLEMENTATION OF A VERTICALLY INTEGRATED ICE SHEET MOMENTUM BALANCE MODEL. [Masters Thesis]. University of Montana; 2013. Available from: https://scholarworks.umt.edu/etd/552

Universiteit Utrecht

3. Charalampidis, C. Response of the ice cap Langfjordjokelen in northern Norway to climate change.

Degree: 2012, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/227437

Subjects/Keywords: Langfjordjokelen; 2D ice-flow model; two-dimensional ice-flow model; SIA; Shallow Ice Approximation; climate change; ice cap; northern Norway; Alternating Direction Implicit method; ADI; future projections; ice dynamics; glacier; dynamic calibration; mass balance

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Charalampidis, C. (2012). Response of the ice cap Langfjordjokelen in northern Norway to climate change. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/227437

Chicago Manual of Style (16^th Edition):

Charalampidis, C. “Response of the ice cap Langfjordjokelen in northern Norway to climate change.” 2012. Masters Thesis, Universiteit Utrecht. Accessed January 26, 2021. http://dspace.library.uu.nl:8080/handle/1874/227437.

MLA Handbook (7^th Edition):

Charalampidis, C. “Response of the ice cap Langfjordjokelen in northern Norway to climate change.” 2012. Web. 26 Jan 2021.

Vancouver:

Charalampidis C. Response of the ice cap Langfjordjokelen in northern Norway to climate change. [Internet] [Masters thesis]. Universiteit Utrecht; 2012. [cited 2021 Jan 26]. Available from: http://dspace.library.uu.nl:8080/handle/1874/227437.

Council of Science Editors:

Charalampidis C. Response of the ice cap Langfjordjokelen in northern Norway to climate change. [Masters Thesis]. Universiteit Utrecht; 2012. Available from: http://dspace.library.uu.nl:8080/handle/1874/227437

4. Håård, Cecilia. Implementation of temperature variations and free surface evolution in the Shallow Ice Approximation (SIA).

Degree: Division of Scientific Computing, 2013, Uppsala University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-202177

► Ice sheets and glaciers constitute an enormous water storage, currently corresponding to a potential sea level rise of almost 70 meters if all ice… (more)

Subjects/Keywords: Shallow Ice Approximation temperature free surface elmer matlab; Other Computer and Information Science; Annan data- och informationsvetenskap

…Shallow Ice Approximation, SOSIA, is a consistent second order perturbation expansion of the… …mentioned earlier, the Shallow Ice Appriximation (SIA) is a much used approximation for… …surface development were implemented in a Matlab version of the Shallow Ice Approximation (… …Shallow Ice Approximation. However, the results were improved as much by simply decreasing the… …Even for large ice sheets there are regions where SIA fails as higher order dynamics…

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Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Håård, C. (2013). Implementation of temperature variations and free surface evolution in the Shallow Ice Approximation (SIA). (Thesis). Uppsala University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-202177

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Håård, Cecilia. “Implementation of temperature variations and free surface evolution in the Shallow Ice Approximation (SIA).” 2013. Thesis, Uppsala University. Accessed January 26, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-202177.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Håård, Cecilia. “Implementation of temperature variations and free surface evolution in the Shallow Ice Approximation (SIA).” 2013. Web. 26 Jan 2021.

Vancouver:

Håård C. Implementation of temperature variations and free surface evolution in the Shallow Ice Approximation (SIA). [Internet] [Thesis]. Uppsala University; 2013. [cited 2021 Jan 26]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-202177.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Håård C. Implementation of temperature variations and free surface evolution in the Shallow Ice Approximation (SIA). [Thesis]. Uppsala University; 2013. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-202177

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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