Parameter Files

To run a simulation, the solution sequence needs many parameters: physical constants, number of iterations, relaxation constant, thickness and surface of the glacier, etc. All of this can be done during model setup in your runme. But for the sake of organization and/or reusability, you might want to store the parameterization commands in a separate file. For example, for the MATLAB interface, you might create a file Parameters.par with contents,

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% GEOMETRY %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

disp('      reading thicknesses');
md.geometry.thickness = InterpFromFile(md.mesh.x, md.mesh.y, thicknesspath, 10);

disp('      reading dem');
md.geometry.surface = InterpFromFile(md.mesh.x, md.mesh.y, surfacepath, 10);

%get base
md.geometry.base = md.geometry.surface - md.geometry.thickness;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% OBSERVATIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

disp('      reading velocities');
md = plugvelocities(md, velocitypath, 0);

disp('      loading temperature');
md.initialization.temperature = InterpFromFile(md.mesh.x, md.mesh.y, temperaturepath, 253);

disp('      creating mass balance rates');
md.smb.mass_balance = InterpFromFile(md.x, md.y, massbalancepath, 1);

disp('      loading geothermal flux'); 
load(heatfluxpath); 
md.basalforcings.geothermalflux = InterpFromGrid(x_m, y_m, heatflux, md.mesh.x, md.mesh.y, 80);

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% MATERIAL %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%flow law 
disp('      creating flow law parameters');
md.materials.rheology_n = 3 * ones(md.mesh.numberofelements, 1);
md.materials.rheology_B = paterson(md.initialization.temperature);

%%%%%%%%%%%%%%%%%%%%%%%%%%% BOUNDARY CONDITIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%

%drag md.drag or stress
md.friction.coefficient = 300 * ones(md.mesh.numberofvertices, 1); %q=1.

%floating ice: no drag
md.friction.coefficient(find(md.mask.ocean_levelset < 0.)) = 0.;
md.friction.p = ones(md.mesh.numberofelements, 1);
md.friction.q = ones(md.mesh.numberofelements, 1);

%Create ice front
md = SetMarineIceSheetBC(md);

As you can see, even though the file extension is par, it is really just a MATLAB script. You can now parameterize your model in your runme with,

>> md = parameterize(md, 'Parameters.par');

For the Python interface, we similarly use Pickle files (pkl) and parameterize with,

>>> md = parameterize(md, 'Parameters.pkl')

Note

• The parameterization must be done on a two dimensional mesh.
• The parameters will be automatically extruded if the mesh is extruded.