Using ISSM Model Data (light version)

PINNICLE is fully compatible with output from the Ice-sheet and Sea-level System Model (ISSM). This ISSM Light data loader is a streamlined alternative to the standard Using ISSM Model Data module. The key difference is that this lighter version does not load any mesh or connectivity information. It only extracts data as pointwise coordinate and associated fields. As a result, all fields are treated as scattered data, allowing users to easily subset the domain without modifying the original ISSM model file.

Overview

ISSM model output typically includes spatial fields such as:

Field

Name in ISSM

Key in PINNICLE

Mesh information

md.mesh.x, md.mesh.y

"x", "y"

Ice velocity components

md.inversion.vx_obs, md.inversion.vy_obs

"u", "v"

Ice thickness

md.geometry.thickness

"H"

Surface elevation

md.geometry.surface

"s"

Basal friction coefficient

md.friction.C

"C"

Ice rheology factor

md.materials.rheology_B`

"B"

Surface mass balance

md.smb.mass_balance-md.balancethickness.thickening_rate

"a"

PINNICLE automatically reads, processes, and extracts relevant fields for training and model initialization, and assigns them to the corresponding variables.

Preprocessing Recommendations

  • Export variables from ISSM with consistent units (SI system: m, s, Pa).

  • Save structured data using saveasstruct(md, filename) in MATLAB to export the ISSM model to a nested struct.

  • Use mesh files (.exp) from ISSM as shapefile input to define simulation domain.

Configuration

To use ISSM data, specify a dataset block in the configuration dictionary:

hp["data"] = {
    "ISSM": {
        "source":"ISSM Light",
        "data_path": "Helheim.mat",
        "data_size": {"u": 4000, "v": 4000, "H": 4000, "s": 4000, "C": None}
    }
}

  • "source": must be set to "ISSM Light" to activate this loader

  • "data_path": Path to the .mat file containing ISSM model

  • "data_size": Number of data points to randomly sample for each variable

  • Set a variable to "None" to infer it is only used as a Dirichlet boundary condition

  • If the key is not mentioned in "data_size", then the corresponding field will not use data from this file

See the Examples section for full demonstrations using ISSM input.