A major overview paper laid out the design of CMIP6, a global program for comparing Earth system model simulations using shared experiment standards. This framework later enabled specialized “endorsed” projects, including ice-sheet-focused experiments, to plug into a common climate-model baseline.
initMIP-Greenland compared how different ice-sheet models create a realistic starting (present-day) Greenland Ice Sheet state, and how that choice affects short forward runs. This was important because ice-sheet projections can vary strongly just from differences in initial conditions, even before future climate forcing is applied.
initMIP-Antarctica ran a similar coordinated test for Antarctica, examining how models respond to idealized changes in snowfall (surface mass balance) and under-ice-shelf melting (basal melt). The study found relatively consistent responses to snowfall changes but very large differences in responses to basal melting, highlighting a key uncertainty for sea-level projections.
A dedicated paper described how ocean conditions from global climate models are translated into boundary conditions for Greenland ice-sheet models. This mattered because many Greenland outlet glaciers end in the ocean, and ocean-driven retreat and melting can strongly affect future ice loss.
ISMIP6 published a detailed protocol for running stand-alone Greenland and Antarctic ice-sheet models using standardized atmospheric and oceanic forcing based on CMIP output. The protocol was designed so that differences among results could be traced to emissions scenarios, climate-model forcing, ice-sheet model structure, and key parameter choices.
A companion protocol described how to compute ice-shelf basal melt rates around Antarctica for ISMIP6 experiments from climate-model ocean fields and observations. Because basal melting can thin ice shelves and speed up inland ice flow, this step is central to projecting Antarctic contributions to sea level.
A multi-model ensemble study reported Greenland Ice Sheet changes through 2100 using the ISMIP6 framework, focusing on how surface melt/runoff and ocean-driven glacier retreat translate into sea-level contribution. The paper also separated major sources of uncertainty, including the choice of ice-sheet model and the climate/ocean forcing used.
A parallel ensemble study synthesized Antarctic Ice Sheet simulations through 2100 under standardized ISMIP6 forcing. Results showed that increased snowfall can partially offset dynamic ice loss in some cases, but that ocean-driven retreat can still produce substantial sea-level rise, with wide spreads across models and forcing choices.
ISMIP6 released a curated dataset of Greenland ice-sheet model outputs for 21st-century projection experiments, supporting reuse and comparison across studies. Public archiving made it easier for researchers to check results, compute sea-level metrics consistently, and build follow-on analyses.
A companion archived dataset provided Antarctic ice-sheet model outputs for ISMIP6 21st-century projection experiments. This open release supported reproducibility and enabled further work on uncertainty, regional contributions, and sensitivity to ocean and atmosphere forcing choices.
Researchers used statistical emulation (a fast surrogate model trained on many simulations) to turn ISMIP6 and glacier intercomparison outputs into probability distributions for 21st-century sea-level contributions under the newer CMIP6 socio-economic scenarios. This helped translate complex model ensembles into scenario-based ranges usable for broader climate risk assessment.
IPCC Working Group I assessed sea-level projections using multiple lines of evidence, including ISMIP6 and emulator-based methods to broaden scenario coverage and uncertainty sampling. This marked a key “handoff” from coordinated model experiments to assessment outcomes that inform policy and planning.
ISMIP6 released a dataset extending Antarctic projection experiments to the year 2300, moving beyond the 2100 horizon that dominates many scenario studies. These longer runs support research on multi-century sea-level commitment, where slow ice-sheet processes can become more important over time.
Earth System Grid Federation (ESGF) archive statistics documented ongoing submissions for ISMIP6 experiments, including coupled climate–ice-sheet simulations labeled “with-ism” (ice sheet model included). This showed a shift from stand-alone ice-sheet experiments toward more integrated Earth system modeling and broader community data sharing.
Ice Sheet Model Intercomparison Project (ISMIP6) and related experiments (2018–present)