부산대학교 도서관

We analyze two preindustrial experiments from the Community Earth System Model version 2 to characterize the impact of sea ice physics on differences in coastal sea ice production around Antarctica and the resulting impact on the ocean and atmosphere. The experiment in which sea ice is a more realistic "mushy" mixture of solid ice and brine has a substantial increase in coastal sea ice frazil and snow ice production that is accompanied by decreasing bottom ice growth and increasing bottom melt. The more realistic "mushy" physics leads to an increase in water mass formation at denser water classes due primarily to surface ice processes. As a result, the subsurface ocean is denser, saltier, and there is an increase in Antarctic Bottom Water formation of ∼0.5 Sv. For the atmosphere, "mushy" ice physics leads to decreased turbulent heat flux and low level cloud cover near the Antarctic coast. Plain Language Summary: We analyze experiments from the Community Earth System Model to better understand the impacts of representing sea ice as a mixture of salty water and solid ice rather than just solid ice. We focus on sea ice produced around the Antarctic coasts and find that the ways in which the sea ice grow and melt change with the two representations of sea ice, but the differences compensate so that the average sea ice state is minimally changed. However, the near surface ocean water is denser in the experiment with sea ice represented by a mix of solid ice and salty water, mainly because the ocean is saltier due to surface sea ice processes. This leads to increased formation of dense Antarctic Bottom Water. In addition, there is less energy input into the atmosphere and less low level cloud cover around the Antarctic coasts in the experiment with the sea ice represented as a mix of salty water and solid ice. Thus, there are important impacts on the Earth system based solely on the way sea ice is represented. Key Points: Choice of sea ice thermodynamics does not lead to large differences in sea ice state due to compensating thermodynamic changesAntarctic Bottom Water production increases by 0.5 Sv and upper ocean becomes denser due to increasing salinity with mushy thermodynamicsWintertime air‐sea fluxes, atmospheric low‐level mixing, and low cloud cover all decrease with mushy thermodynamics [ABSTRACT FROM AUTHOR]