GIA/GRDMIP is a coordinated international model intercomparison project investigating how the Earth responds to ice-sheet changes. We compare predictions of solid Earth deformation, gravity-field change, and Earth rotation across a diverse range of numerical models to better quantify uncertainties in glacial isostatic adjustment (GIA) and gravitational, rotational, and deformational (GRD) processes.
The project consists of two complementary activities:
GIAMIP — intercomparison of Earth responses to ice-sheet changes throughout the Last Glacial Cycle.
GRDMIP — intercomparison of Earth responses to future ice-sheet evolution.
By bringing together models with different Earth rheologies, numerical formulations, and ice-sheet histories, GIA/GRDMIP provides community benchmarks and ensemble predictions that support the interpretation of geodetic observations, relative sea-level records, and paleo-sea-level data. All protocols, model outputs, and analysis products are made publicly available to facilitate research across the sea-level, geodesy, and cryosphere communities.