About ISSM

Here is an overview of what ISSM can do:
Anisotropic mesh adaptation
to reduce optimize the number of elements in the computational mesh, ISSM relies on static anisotropic mesh adaptation. InSAR derived surface velocities are used to generate a mesh that minimizes interpolation errors.

(a) InSAR surface velocity interpolated on a regular mesh (in white). (b) InSAR surface velocity interpolated on adapted mesh. Both meshes comprise 1,500 elements.
Anisotropic static adaptive mesh of Jakobshavn Isbrae, West Greenland.
Anisotropic static adaptive mesh of Jakobshavn Isbrae, West Greenland. (a) InSAR surface velocity interpolated on a regular mesh (in white). (b) InSAR surface velocity interpolated on adapted mesh. Both meshes comprise 1,500 elements.
Inversions
Control methods are crucial in ice sheet modeling, as they provide an invaluable technique to infer non-measurable quantities (such as basal friction for grounded ice, or the rheology for ice shelves) from observations. Here is an example from Pine Island Glacier.
Pine Island Glacier observed velocity
InSAR derived observed velocity
The basal drag parameter (on the left) is inferred from the observation by minimizing the misfit between the observed and the modeled velocity field. Here are the results after 0, 1, 5 and 10 iterations.
Pine island basal drag inversion
Pine island basal drag inversion
(left)Inferred basal drag coefficient, (right) Modeled velocity
Transient runs
ISSM is capable of accepting transient forcings. Here is an example of a square ice shelf responding to a saw-tooth surface mass balance forcing (black) over a period of 2000 years.
Transient evolution