Eemian Greenland ice sheet simulated with a higher-order model shows strong sensitivity to surface mass balance forcing

Abstract. The Greenland ice sheetcontributes increasingly to global sea levelrise. Its history during past warm intervals is a valuable reference for future sea levelprojections. We present ice sheetsimulations for the Eemian interglacialperiod ( ∼130 000 to 115 000 years ago), a period with warmer-than-present summer climate over Greenland. The evolution of the Eemian Greenland ice sheetis simulated with a 3-D higher-order ice sheet model, forced with a surface mass balancederived from regional climate simulations. Sensitivity experiments with various surface mass balances, basal friction, and iceflow approximations are discussed. The surface mass balanceforcing is identified as the controlling factor setting the minimum in Eemian icevolume, emphasizing the importance of a reliable surface mass balancemodel. Furthermore, the results indicate that the surface mass balanceforcing is more important than the representation of iceflow for simulating the large-scale ice sheetevolution. This implies that modeling of the future contribution of the Greenland ice sheetto sea level rise highly depends on an accurate surface mass balance.