Quantifying the snowmelt-albedo feedback at Neumayer Station, East Antarctica

Abstract

We use 24 years (1992-2016) of high-quality meteorological observations at Neumayer Station, East Antarctica, to force a surface energy balance model. The modelled 24-year cumulative surface melt at Neumayer amounts to 1154 mm water equivalent (w.e.), with only a small uncertainty ( ±3 mm w.e.) from random measurement errors. Results are more sensitive to the chosen value for the surface momentum roughness length and new snow density, yielding a range of 900-1220 mm w.e. Melt at Neumayer occurs only in the months November to February, with a summer average of 50 mm w.e. and large interannual variability ( σ Combining double low line42 mm w.e.). This is a small value compared to an annual average (1992-2016) accumulation of 415±86 mm w.e. Absorbed shortwave radiation is the dominant driver of temporal melt variability at Neumayer. To assess the importance of the snowmelt-albedo feedback we include and calibrate an albedo parameterisation in the surface energy balance model. We show that, without the snowmelt-albedo feedback, surface melt at Neumayer would be approximately 3 times weaker, demonstrating how important it is to correctly represent this feedback in model simulations of surface melt in Antarctica.