Preprints
https://doi.org/10.5194/tc-2021-280
https://doi.org/10.5194/tc-2021-280

  03 Sep 2021

03 Sep 2021

Review status: a revised version of this preprint is currently under review for the journal TC.

A new vertically integrated, MOno-Layer Higher-Order ice flow model (MOLHO)

Thiago Dias dos Santos1,2, Mathieu Morlighem1,3, and Douglas Brinkerhoff4 Thiago Dias dos Santos et al.
  • 1Department of Earth System Science, University of California, Irvine, CA, USA
  • 2Centro Polar e Climático, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
  • 3Department of Earth Sciences, Dartmouth College, Hanover, NH, USA
  • 4Department of Computer Science, University of Montana, Missoula, MT, USA

Abstract. Numerical simulations of ice sheets rely on the momentum balance to determine how ice velocities change as the geometry of the system evolves. Ice is generally assumed to follow a Stokes flow with a nonlinear viscosity. Several approximations have been proposed in order to lower the computational cost of a full-Stokes stress balance. A popular option is the Blatter-Pattyn or Higher-Order model (HO), which consists of a three-dimensional set of equations that solves the horizontal velocities only. However, it still remains computationally expensive for long transient simulations. Here we present a depth-integrated formulation of the HO model, which can be solved on a two-dimensional mesh in the horizontal plane. We employ a specific polynomial function to describe the vertical variation of the velocity, which allows us to integrate the vertical dimension using a semi-analytic integration. We assess the performance of this MOno-Layer Higher-Order model (MOLHO) to compute ice velocities and simulate grounding line dynamics on standard benchmarks (ISMIP-HOM and MISMIP3D). We compare MOLHO results to the ones obtained with the original three-dimensional HO model. We also compare the time performance of both models in time-dependent runs. Our results show that the ice velocities and grounding line positions obtained with MOLHO are in very good agreement with the ones from HO. In terms of computing time, MOLHO requires less than 10 % of the computational time of a typical HO model, for the same simulations. These results suggest that the MOno-Layer Higher-Order formulation provides improved computational time performance and a comparable accuracy compared to the HO formulation, which opens the door to Higher-Order paleo simulations.

Thiago Dias dos Santos et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on tc-2021-280', Daniel Shapero, 05 Oct 2021
    • AC1: 'Reply on RC1', Thiago Dias dos Santos, 22 Nov 2021
  • RC2: 'Comment on tc-2021-280', Anonymous Referee #2, 11 Oct 2021
    • AC2: 'Reply on RC2', Thiago Dias dos Santos, 22 Nov 2021

Thiago Dias dos Santos et al.

Thiago Dias dos Santos et al.

Viewed

Total article views: 520 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
410 97 13 520 5 3
  • HTML: 410
  • PDF: 97
  • XML: 13
  • Total: 520
  • BibTeX: 5
  • EndNote: 3
Views and downloads (calculated since 03 Sep 2021)
Cumulative views and downloads (calculated since 03 Sep 2021)

Viewed (geographical distribution)

Total article views: 492 (including HTML, PDF, and XML) Thereof 492 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 02 Dec 2021
Download
Short summary
Projecting the future evolution of Greenland and Antarctica and their potential contribution to sea level rise often relies on computer simulations carried out by numerical ice sheet models. Here we present a new vertically integrated ice sheet model, and assess its performance using different benchmarks. The new model shows results comparable to a three-dimensional model at relatively lower computational cost, suggesting that its is an excellent alternative for long-term simulations.