Developments within an Antarctic ocean model configuration: balancing regional characteristics with circumpolar modelling challenges

The West Antarctic Ice Sheet is rapidly losing mass due to ocean-driven ice shelf melt, contributing to sea level rise. This ice shelf melt is typically studied using either global climate models without open ice shelf cavities or regional models with ice shelf cavities. We will present updates on development work with a  ¼° circumpolar Antarctic NEMO configuration that extends from the continent to 50 degrees south to allow for interaction between regions and which includes sea ice, icebergs, and open ice shelf cavities with BedMachinev3 bathymetry. While experiments forced by ERA5 atmospheric conditions are stable over the observational period (1979-now), there is a tendency for reduction of stratification in the water column in the Weddell Sea, making it prone to destabilization when forced with historical conditions and resulting in excess deep convection. We will present results from testing of the sensitivity to excess Weddell Sea deep convection in the model configuration, leading to a set of sea ice parameter combinations that appear to reduce convection, while maintaining desired ice shelf cavity properties. We will also discuss some explorations into mixing representations within ice shelf cavities. Moving forward, we plan to use this configuration to study attribution questions of ocean-driven melt of the West Antarctic Ice Sheet.