pism

PISM, short for Parallel Ice Sheet Model, is an open-source numerical model used to simulate the evolution of ice sheets and their contribution to sea level. It is designed for continental-scale, long-term simulations and is widely used in glaciology and climate research.

The model solves the conservation of mass for ice and employs momentum approximations appropriate for ice sheets, commonly including the shallow-ice approximation (SIA) and the shallow-shelf approximation (SSA) for faster-flowing regions. It incorporates mechanisms such as surface mass balance, basal sliding, and calving, and can represent bed topography and bed properties. PISM can also include thermodynamic aspects through temperature or enthalpy formulations.

Implementation and usage: PISM is written in C++ with parallel execution via MPI, intended for high-performance computing. It uses a finite-volume or finite-difference discretization on structured or unstructured grids, supports variable resolution, and can be driven by climate forcing data or coupled to climate models.

Applications and development: PISM is used to study past and future ice-sheet behavior, paleo-climate reconstructions, and projections of sea-level rise. It is developed and maintained by a community of researchers and is distributed with documentation and tutorials through public repositories as an open-source project.

Overview: As a flexible framework, PISM supports modular components for ice dynamics, thermodynamics, and forcing, enabling researchers to test hypotheses about ice-sheet response to climate change in a transparent, reproducible manner.