Analysis of the surface mass balance for deglacial climate simulations

Abstract. A realistic simulation of the surface mass balance (SMB) is essential for simulating past and future ice-sheet changes. As most state-of-the-art Earth system models (ESMs) are not capable realistically representing processes determining SMB, studies SMB limited to observations regional climate cover last century near only. Using transient simulations with Max Planck Institute ESM in combination an energy model (EBM), we extend previous research study changes equilibrium line altitude (ELA) Northern Hemisphere ice sheets throughout deglaciation. The EBM used calculate downscale onto a higher spatial resolution than native grid allows variations due topographic gradients resolved by ESM. An evaluation historical conditions (1980–2010) shows that derived SMBs compare well from modeling. Throughout deglaciation, insolation dominate Greenland SMB. increase associated warming early deglaciation result ELA increase. caused compensating effects melt accumulation: atmosphere leads at low elevations along margins, while it results accumulation levels as warmer precipitates more. After 13 ka, begins dominate, decreases. decline summer after 9 ka increasing decreasing ELA. Superimposed on these long-term centennial-scale episodes abrupt decreases related slowdowns Atlantic meridional overturning circulation (AMOC) lead cooling over Hemisphere.