The Future of Sea Ice Modeling: Where Do We Go from Here?

Earth System Models (ESMs) include a sea ice component to physically represent sea ice changes and impacts on planetary albedo and ocean circulation (Manabe & Stouffer, 1980). Most contemporary sea ice models describe the sea ice pack as a continuum material, a principle laid by the AIDJEX (Arctic Ice Dynamics Joint EXperiment) group in the 1970s (Pritchard, 1980). Initially intended for climate studies, the sea ice components in ESMs are now used across a wide range of resolutions, including very high resolutions more than 100 times finer than those they were designed for, in an increasingly wide range of applications that challenge the AIDJEX model foundations (Coon et al., 2007), including operational weather and marine forecasts. It is therefore sensible to question the applicability of contemporary sea ice models to these applications. Are there better alternatives available? Large advances in high performance computing (HPC) have been made over the last few decades and this trend will continue. What constraints and opportunities will these HPC changes provide for contemporary sea ice models? Can continuum models scale well for use in exascale computing? To address these important questions, members of the sea ice modelling community met in September 2019 for a workshop in Laugarvatn, Iceland. Thirty-two sea ice modelling scientists from 11 countries across Europe and North America attended, spanning 3 key areas: (i) developers of sea-ice models; (ii) users of sea-ice models in an ESM context; (iii) users of sea64 ice models for operational forecasting and (re)analyses. The workshop was structured around 2 key themes: 1. Scientific and technical validity and limitations of the physics and numerical approaches used in the current models 2. Physical processes and complexity: bridging the gap between weather and climate requirements For each theme, 5 keynote speakers were invited to address the motivating questions and stimulate debate. Further details can be found in the Supplementary Material.

[1]  Klaus Zimmermann,et al.  Earth System Model Evaluation Tool (ESMValTool) v2.0 – technical overview , 2020, Geoscientific Model Development.

[2]  M. Losch,et al.  Feature-based comparison of sea ice deformation in lead-permitting sea ice simulations , 2020, The Cryosphere.

[3]  M. Losch,et al.  Simulating intersection angles between conjugate faults in sea ice with different viscous–plastic rheologies , 2019, The Cryosphere.

[4]  Patrick Scholz,et al.  Fast EVP Solutions in a High‐Resolution Sea Ice Model , 2019, Journal of Advances in Modeling Earth Systems.

[5]  anonymous.  On the multi-fractal scaling properties of sea ice deformation , 2019 .

[6]  T. Williams,et al.  On the multi-fractal scaling properties of sea ice deformation , 2019, The Cryosphere.

[7]  D. Feltham,et al.  Stress and deformation characteristics of sea ice in a high-resolution, anisotropic sea ice model , 2018, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[8]  P. Kushner,et al.  Reassessing Sea Ice Drift and Its Relationship to Long‐Term Arctic Sea Ice Loss in Coupled Climate Models , 2018, Journal of Geophysical Research: Oceans.

[9]  T. Fichefet,et al.  Relationships between Arctic sea ice drift and strength modelled by NEMO-LIM3.6 , 2017 .

[10]  Thomas Richter,et al.  A modified global Newton solver for viscous-plastic sea ice models , 2017 .

[11]  Sergey Danilov,et al.  A comparison of viscous-plastic sea ice solvers with and without replacement pressure , 2017 .

[12]  P. Saramito,et al.  Ice bridges and ridges in the Maxwell-EB sea ice rheology , 2016 .

[13]  J. Lemieux,et al.  Improving the simulation of landfast ice by combining tensile strength and a parameterization for grounded ridges , 2016 .

[14]  François Massonnet,et al.  The CMIP6 Sea-Ice Model Intercomparison Project (SIMIP): understanding sea ice through climate-model simulations , 2016 .

[15]  Mike Ashworth,et al.  Prospects for improving the representation of coastal and shelf seas in global ocean models , 2016 .

[16]  Pierre Saramito,et al.  A Maxwell-elasto-brittle rheology for sea ice modelling , 2016 .

[17]  Sylvain Bouillon,et al.  neXtSIM: a new Lagrangian sea ice model , 2015 .

[18]  Gurvan Madec,et al.  The Louvain-La-Neuve sea ice model LIM3.6: global and regional capabilities , 2015 .

[19]  J. Lemieux,et al.  A basal stress parameterization for modeling landfast ice , 2015 .

[20]  Jean-François Lemieux,et al.  A parallel Jacobian-free Newton-Krylov solver for a coupled sea ice-ocean model , 2014, J. Comput. Phys..

[21]  Michel Tsamados,et al.  Impact of a new anisotropic rheology on simulations of Arctic sea ice , 2013 .

[22]  David M. Holland,et al.  A comparison of the Jacobian-free Newton-Krylov method and the EVP model for solving the sea ice momentum equation with a viscous-plastic formulation: A serial algorithm study , 2012, J. Comput. Phys..

[23]  Jean-Marc Molines,et al.  Evaluation of high-resolution sea ice models on the basis of statistical and scaling properties of Arctic sea ice drift and deformation , 2009 .

[24]  Ron Kwok,et al.  Variability of sea ice simulations assessed with RGPS kinematics , 2008 .

[25]  Daniel L. Feltham,et al.  Sea Ice Rheology , 2008 .

[26]  D. Sulsky,et al.  Arctic Ice Dynamics Joint Experiment (AIDJEX) assumptions revisited and found inadequate , 2007 .

[27]  H. L. Miller,et al.  Climate Change 2007: The Physical Science Basis , 2007 .

[28]  M. Hopkins,et al.  Floe formation in Arctic sea ice , 2006 .

[29]  Daniel L. Feltham,et al.  Modelling the rheology of sea ice as a collection of diamond-shaped floes , 2006 .

[30]  M. Hopkins,et al.  Formation of an aggregate scale in Arctic sea ice , 2004 .

[31]  R. Kwok,et al.  Seasonal ice area and volume production of the Arctic Ocean: November 1996 through April 1997 , 2002 .

[32]  Peter Lemke,et al.  Results of the Sea Ice Model Intercomparison Project: Evaluation of sea ice rheology schemes for use in climate simulations , 2000 .

[33]  E. Hunke,et al.  An Elastic–Viscous–Plastic Model for Sea Ice Dynamics , 1996 .

[34]  L. Morland,et al.  A two-dimensional model for the dynamics of sea ice , 1994, Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences.

[35]  Syukuro Manabe,et al.  Sensitivity of a global climate model to an increase of CO2 concentration in the atmosphere , 1980 .

[36]  W. Hibler.  A Dynamic Thermodynamic Sea Ice Model , 1979 .