Specific surface area of surface snow along a traverse route between a coastal base near Syowa Station and Dome Fuji in East Antarctica from November 2021 to January 2022

To better understand the surface properties of the Antarctic ice sheet, we measured the specific surface area (SSA) of surface snow during two round-trip traverses between a coastal base near Syowa Station, located 15 km inland from the coast, and Dome Fuji, located 1066 km inland, in East Antarctica from November 2021 to January 2022. Using a handheld integrating sphere snow grain sizer (HISSGraS), which directly measures snow surface without sampling, we collected 215 sets of SSA data, each set comprising measurements from 10 surfaces along a 20 m transect. The measured SSA shows no elevation or temperature dependence at 15-500 km from the coast at elevations of 615-3000 m, with a mean and standard deviation of 25 +- 9 m^2 kg^-1. Beyond this area, SSA increases toward the interior, reaching 45 +- 11 m^2 kg^-1 between 800 and 1066 km from the coast, at elevations of 3600-3800 m. SSA shows no significant systematic differences between the traverses but changes dynamically depending on surface morphologies and short-term meteorological events. This includes that: (i) glazed surfaces, an accumulation-hiatus form appeared in katabatic wind areas, show low SSA (19 +- 4 m^2 kg^-1), decreasing the mean SSA and increasing SSA variability in the areas. (ii) Snow deposition increases surface snow SSA to 60-110 m^2 kg^-1, but it is inhibited by snow drifting at wind speeds above 5 m s^-1. Our analyses for these observations clarified that temperature-dependent snow metamorphism, snowfall frequency, and wind-driven inhibition of snow deposition play crucial roles in the spatial variation of surface snow SSA in the Antarctic inland. The extensive dataset will enable the validation of satellite-derived and model-simulated SSA variations across Antarctica.