Veris: a versatile sea ice simulator in JAX

Veris implements sea ice dynamics and thermodynamics using JAX for array operations. It supports forward and reverse modes of automatic differentiation and parallel execution on CPUs and GPUs. The package includes several setups to show how to use it.

This documentation describes Veris 0.2.1. The stable documentation follows the latest published release.

Veris was derived from the MITgcm SEAICE package. Jan Philipp Gärtner created the original Veris implementation as part of his Master’s thesis.

Usage

• Getting started
  • Installation
  • Setting up a model
  • Running Veris
  • Extending Veris
• Define, run and resume a sea-ice experiment
  • Observing the trajectory
  • Loading selected fields
  • Next steps
• Prescribed ocean geometry and custom fields
• Add and reproduce an experiment
  • Start with prescribed ocean geometry
  • Run from Python
  • Run from the CLI
  • Inspect and export
  • Defaults and overrides
  • Register a field factory
  • Local and distributed execution
• Command line tools
  • All commands
  • Show preconfigured setups
  • Copy a selected setup
  • Run a setup
  • Grouped overrides and shared execution
  • Inspect and export definitions
  • Module driver output options

Reference

• Scientific package hierarchy
  • Implementation tree
  • Canonical imports
• Model setups
  • Island
  • Dynamics only
  • Growth only
  • Parallel dynamics
• Scan rollouts and checkpointing
  • Physics modes
  • Selected observations and diagnostics
  • Time-varying forcing and AD
  • Sharded rollouts
  • Host output and timing
• Prescribed ocean geometry
• Model settings
  • Horizontal boundaries
  • Floating-point precision
  • Registry defaults
• Physical constants
  • Registry defaults
• State fields
  • NetCDF metadata
  • Registry defaults
  • Coupling diagnostics
• Calendar-aware input and output
  • Floating-point precision
  • Sampling and calendar windows
  • Direct sampling
  • Scheduled integration
  • Final snapshots and selected input
  • Automatic differentiation
  • Distributed output
  • Command-line output
  • Registry defaults
• Ocean boundary budgets
  • Snow enthalpy and cleanup
  • Validity and independent references
• Automatic differentiation at model boundaries
  • Physical parameter continuations
  • Zero norms
  • Inactive branches
  • Free drift
  • Thresholds and validation
  • Float32 surface-temperature derivatives
  • Differentiating complete rollouts

Python API

• Python API
  • Model data and metadata
  • Experiment definitions
  • Simulation lifecycle
  • Initialization and presets
  • Integration
  • Physics kernels
  • Halos and parallel execution
  • Input and output

Development

• Developing Veris

Source code: team-ocean/veris.