Community Atmosphere Model Gets a New Dynamical Core
Department of Energy (DOE) supported global atmosphere modelers have developed, implemented, and released a new method for dividing up the global atmosphere into grids upon which the atmospheric dynamical equations are solved, also known as the model’s “dynamical core.” The new method has two very important new features: first, it can run very efficiently on computers with multiple processors (it “scales well”), and second, it can be run with a flexible mesh enabling it to zoom in with finer grid spacing over some regions while running with coarser grid spacing elsewhere. The new dynamical core, the Spectral Element version of the Community Atmosphere Model (CAM-SE) is now included in the Community Climate System Model version 4 (CCSM4) and in the Community Earth System Model version 1 (CESM1). CAM-SE dynamics are highly accurate in terms of conserving mass and energy, making it very suitable for tracer transport. The CAM-SE also has features that indicate it should perform very well for capturing the variability and frequency of occurrence of mesoscale events such as storm fronts if the model is run at sufficiently high resolution. Overall, this new dynamical core performs as well as previous dynamical cores compared with observations, but runs more efficiently and will be more suitable for capturing high-resolution atmospheric features needed for DOE climate modeling.
Evans, K. J., P. H. Lauritzen, S. K. Mishra, R. B. Neale, M. A. Taylor, and J. J. Tribbia. 2013. “AMIP Simulations with the CAM4 Spectral Element Dynamical Core,” Journal of Climate 26, 689-709.