We examined snow sinks caused by snow and sea ice interactions (snow-ice formation and sub-parcel snow mass redistribution) on level sea ice in the Arctic. We coupled SnowModel-LG, a modeling system adapted for snow depth and density reconstruction over sea ice, with HIGHTSI, a 1-D thermodynamic sea ice model, to create SMLG_HS. Pan-Arctic model simulations spanned from 1 August 1980 through 31 July 2022. Evaluation of SMLG_HS against snow depth, snow-ice, and sea ice thickness observations highlighted the importance of snow mass changes due to snow redistribution processes. Without accounting for these processes, snow on level ice was overestimated, resulting in underestimation of level ice thickness and overestimation of snow-ice thickness. We show that snow depth on level ice needs to be reduced by 40 % to simulate both snow and level ice thicknesses realistically. Guided by this result, we re-evaluated snow-ice formation. Our findings suggest that, on average over the whole Arctic, snow sinks on level sea ice can reduce snow depth by 3.5 % and increase snow density by 2.3 %.
