Supporting Community Use of the Community Earth System Model for Polar Science
Climate models have consistently indicated that polar regions are among the most sensitive to perturbations in climate forcing. This has been born out in recent years as the Arctic has undergone significant warming and unprecedented sea ice loss. In contrast, Antarctic sea ice has experienced little consistent long-term hemispheric change. Climate model studies suggest this is related to Southern Ocean heat uptake and is influenced by trends in atmospheric modes of variability. Although a basic understanding has been obtained, much remains unknown about the complex interactions in both polar regions and the relative role of various processes. The current generation of Earth system models have higher resolution and incorporate new physics and capabilities. As such, they provide increasingly powerful virtual laboratories to investigate polar climate processes. Model improvements based on observations and process understanding are needed to further increase the fidelity and predictive capability of earth system model projections. Broader impacts: The complexity and inaccessibility of existing earth system models has long been a barrier to their widespread use. The Community Earth System Model (CESM), which is based at the National Center for Atmospheric Research (NCAR), is a true community model, built and used by the broad earth science research community to understand a wide variety of processes. Unlike other earth system modeling efforts, the CESM source code and simulation output are made freely available to the scientific community through supported releases. The broad research community is invited to participate in model development, analysis, and experimental design through involvement in working groups, including the Polar Climate Working Group (PCWG), that are open to all participants. Enabling fruitful interactions that allow the broader research community to be involved in the development and use of an earth system model requires resources. This research will enable the use and development of CESM by the polar science community through funding to support liaisons between the Polar Climate Working Group and the scientific community.