Air-Ice-Ocean Coupling During Cyclone Events in the Central Arctic

Studies over the last decade have suggested that both thermodynamic and dynamic interactions between the atmosphere and the underlying sea ice are significant during Arctic cyclone events, and that impacts on the upper ocean also occur. Mid-winter thermodynamic interactions include warming of the sea ice surface through enhanced longwave radiative fluxes, often leading to thermal waves penetrating the sea ice and reducing mid-winter ice growth rates. The thermodynamic forcing also destabilizes the atmospheric boundary layer through the surface warming as a cyclone approaches and by cold-air advection behind the departing cold front. The sudden, rapid destabilization behind the cold front greatly enhances the dynamic interaction between the atmosphere and sea ice through the enhanced air-ice stress occurring during this destabilized period. This enhanced stress greatly impacts ice motion and deformation. Which in turn, through drag on the upper ocean, impacts upper ocean currents.

Multidisciplinary observations obtained during the Multi-Disciplinary Study of the Arctic Climate (MOSAiC) field program from Oct 2019 to Sep 2020 are used to illustrate these thermodynamic and dynamic air-ice-ocean interactions. Furthermore, the ability of two coupled models to faithfully represent some of the observed air-ice and ice-ocean interactions are examined for one midwinter case.