E11.5 Evaluation of E3SMv1 Atmospheric Simulations Over the Southern Polar Region

Abstract

This work aims to evaluate E3SMv1 simulations over the Southern polar region to provide an assessment of the simulated atmospheric forcings that exert a strong influence on the cryosphere system around the Antarctica and the dynamical connection between Southern Polar regions and lower latitudes. The atmosphere model simulations used are part of the E3SMv1 DECK (Diagnostic, Evaluation and Characterization of Klima) experiments, with prescribed observational sea surface temperature and ice coverage. The analysis of the forcings focuses on the simulated atmospheric climatology. The Southern Annular Mode (SAM) and its variability are analyzed to evaluate the simulated dynamical connection between high and low latitudes in the model. Preliminary analysis shows that the simulated cloud, precipitation, and radiation fields, in comparison with limited available observations, exhibits large discrepancies that are with strong seasonality and sharp contrast over ice sheets, on the periphery of the ice sheets and over the circumpolar southern oceans. These are clear indications that issues in cloud physics, surface-air interactions and the ability to reproduce synoptic scale weather systems over the region may all have a large influence on the model results. For this consideration, the synoptic regimes are classified and evaluated to characterize the model behavior in simulating large-scale circulations and separate the influence of dynamics from model physics on simulated precipitation, cloud and radiation. The outcome of this work will be used to guide the improvement of the simulations of the atmospheric forcings important to modeling the cryosphere system.