Abstract
The thermodynamic growth of sea ice is a critical factor in the mass
balance of Arctic sea ice, which has important implications for Arctic
communities and the global climate. However, the magnitude by which snow
atop Arctic sea ice limits thermodynamic ice growth is still not fully
understood. Prior work has shown that the wind-driven snow
redistribution could significantly modify the heat conduction through
the snow cover and hence the rate of thermodynamic ice growth. However,
the effects of snow redistribution on sea ice growth have not been
quantified and are not well represented in climate models. We use
observations from the MOSAiC expedition to show how different facets of
snow redistribution can enhance or reduce heat conduction through the
snow cover for the same mean snow thickness. The net effect depends on
ice topography and environmental conditions. For example, snow
redistribution onto young ice in April at MOSAiC reduced heat conduction
by approximately 5-15%. We quantify the impact winter and springtime
snow redistribution events on the heat conduction on deformed, level,
and young ice. We explore the implications of these snow redistribution
processes in the Community Earth System Model and discuss priorities for
improving climate models.