Quantifying multi-model uncertainty in ice sheet projections

Abstract:

The ISMIP6 project has allowed far more comprehensive assessment of uncertainties for projections of the ice sheet contribution to sea level rise than ever before. But, more than that, the experimental design -- using multiple GCM forcings, high and low emissions scenarios, and identical parameter perturbations across all ice sheet models -- has allowed the unique advance of characterising the ice sheet multi-model response in a single statistical framework called an emulator. This allows the gaps in the design to be filled more thoroughly than could ever be feasibly achieved with the original ice sheet models, allowing estimation of the full impact of the forcing and parameter uncertainties on projections. We present results from such a framework.