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We evaluate modelled Antarctic ice sheet (AIS) near-surface climate, surface
mass balance (SMB) and surface energy balance (SEB) from the updated polar
version of the regional atmospheric climate model, RACMO2 (1979–2016). The
updated model, referred to as RACMO2.3p2, incorporates upper-air relaxation,
a revised topography, tuned parameters in the cloud scheme to generate more
precipitation towards the AIS interior and modified snow properties reducing
drifting snow sublimation and increasing surface snowmelt. Comparisons of RACMO2 model output with several independent observational
data show that the existing biases in AIS temperature, radiative fluxes and
SMB components are further reduced with respect to the previous model
version. The model-integrated annual average SMB for the ice sheet including
ice shelves (minus the Antarctic Peninsula, AP) now amounts to
2229 Gt y−1, with an interannual variability of 109 Gt y−1. The
largest improvement is found in modelled surface snowmelt, which now compares
well with satellite and weather station observations. For the high-resolution
(∼ 5.5 km) AP simulation, results remain comparable to earlier
studies. The updated model provides a new, high-resolution data set of the contemporary
near-surface climate and SMB of the AIS; this model version will be used for
future climate scenario projections in a forthcoming study.