Regionally Refined Modeling of the Atmosphere in the Energy Exascale Earth System Model
The increasing complexity and resolution of Earth system models significantly increases the computational burden of running the models, which challenges traditional approaches to evaluating the performance of those models. This has motivated the development of new techniques to investigate these new complexities and resolutions without the associated computational cost. Regionally refined meshes (RRM), static patches of high resolution with a component of an Earth system model, are one such example of approaches used to investigate model behavior at increased resolution. These static patches of refinement are coupled with the remainder of the global domain with no offline forcing. To date, the Energy Exascale Earth System Model (E3SM) has variable resolution in its atmosphere, land, ocean, and ice components. The atmospheric component itself has several RRM grid configurations over multiple areas of interest including the contiguous United States, Eastern North Atlantic, Tropical Western Pacific, and Antarctica. In this work, the RRM configurations in the atmospheric component of the E3SM will be presented, for low resolutions of 1 degree and high resolutions of 1/4, 1/8, and 1/16 along with regional and global idealized climatologies. The resolution of the other component models such as land and ocean will also be presented. The shape and resolutions of grids will be evaluated to assess teleconnectic impacts of larger areas of refinement and any artifacts of grid imprinting for the various grids. An evaluation of extremes will be given over these grids to compare to their uniform lower resolution counterparts. When possible, comparisons will be made against available observations.