Local sea level changes due to Greenland ice sheet mass changes from 1970 to 2100

The Greenland ice sheet is melting at an increasing rate and is predicted to have a large contribution to sea level change by 2100. Future climate over Greenland, which determines the ice sheet’s surface melt and marine-terminating glacier retreat, represents a major source of uncertainty for Greenland ice sheet evolution (ISMIP6). In this study, we explore the Greenland ice sheet contribution to sea level change from 1960 to 2100 and quantify how uncertainties in projected climate change and Earth rheological structure shape global and local sea level changes and their spatio-temporal variability.

Ice load history is provided by simulations following the ISMIP6 protocol. To project regional sea level changes, we employ two different gravitationally self-consistent sea level models. We use the pseudo-spectral sea level model described in Gomez et al. (2010). To test the sensitivity of projections to surface resolution and Earth structure, the experiments are repeated with the finite volume sea level model SEAKON (Latychev 2005) that includes 3D variations in Earth structure and grid refinement capabilities to reach ~5 km surface resolution over Greenland.

Results highlight the spatial variability of projected sea level for communities along the Greenlandic coastline, and contrast local changes to farfield sea level rise for Pacific Islands. With a spread of -1.00m to -2.96m sea level change by 2100 around Ilulissat, West Greenland, our results are up to three times the value provided by the NASA IPCC sea level tool (-0.8m) and emphasize the need for more studies addressing local sea level changes.