TY - JOUR
T1 - Greenland ice sheet surface mass balance: evaluating simulations and making projections with regional climate models
AU - Rae, James
AU - Aðalgeirsdóttir, Gudfinna
AU - Edwards, Tamsin L
AU - Fettweis, Xavier
AU - Hewitt, Helene
AU - Lowe, Jason
AU - Lucas-Picher, Philippe
AU - Mottram, Ruth
AU - Payne, A J
AU - Ridley, Jeff
AU - Shannon, Sarah R
AU - van de Berg, Willem Jan
AU - van de Wal, Roderik
AU - van den Broeke, Michiel
PY - 2012/11/9
Y1 - 2012/11/9
N2 - Four high-resolution regional climate models (RCMs) have been set up for the area of Greenland, with the aim of providing future projections of Greenland ice sheet surface mass balance (SMB), and its contribution to sea level rise, with greater accuracy than is possible from coarser-resolution general circulation models (GCMs). This is the first time an intercomparison has been carried out of RCM results for Greenland climate and SMB. Output from RCM simulations for the recent past with the four RCMs is evaluated against available observations. The evaluation highlights the importance of using a detailed snow physics scheme, especially regarding the representations of albedo and meltwater refreezing. Simulations with three of the RCMs for the 21st century using SRES scenario A1B from two GCMs produce trends of between −5.5 and −1.1 Gt yr−2 in SMB (equivalent to +0.015 and +0.003mm sea level equivalent yr−2), with trends of smaller magnitude for scenario E1, in which emissions are mitigated. Results from one of the RCMs whose present-day simulation is most realistic indi- cate that an annual mean near-surface air temperature increase over Greenland of ∼ 2◦ C would be required for the mass loss to increase such that it exceeds accumulation, thereby causing the SMB to become negative, which hasbeen suggested as a threshold beyond which the ice sheet would eventually be eliminated.
AB - Four high-resolution regional climate models (RCMs) have been set up for the area of Greenland, with the aim of providing future projections of Greenland ice sheet surface mass balance (SMB), and its contribution to sea level rise, with greater accuracy than is possible from coarser-resolution general circulation models (GCMs). This is the first time an intercomparison has been carried out of RCM results for Greenland climate and SMB. Output from RCM simulations for the recent past with the four RCMs is evaluated against available observations. The evaluation highlights the importance of using a detailed snow physics scheme, especially regarding the representations of albedo and meltwater refreezing. Simulations with three of the RCMs for the 21st century using SRES scenario A1B from two GCMs produce trends of between −5.5 and −1.1 Gt yr−2 in SMB (equivalent to +0.015 and +0.003mm sea level equivalent yr−2), with trends of smaller magnitude for scenario E1, in which emissions are mitigated. Results from one of the RCMs whose present-day simulation is most realistic indi- cate that an annual mean near-surface air temperature increase over Greenland of ∼ 2◦ C would be required for the mass loss to increase such that it exceeds accumulation, thereby causing the SMB to become negative, which hasbeen suggested as a threshold beyond which the ice sheet would eventually be eliminated.
M3 - Article (Academic Journal)
SN - 1994-0416
VL - 6
SP - 1275
EP - 1294
JO - Cryosphere
JF - Cryosphere
ER -
