A scalable high-order discontinuous galerkin method for global atmospheric modeling^†

The future evolution of the community-climate system model into an Earth system model will require a highly scalable and accurate flux-form formulation of atmospheric dynamics .Inherently conservative numerical schemes are of fundamental importance in atmospheric and climate modeling to pertain to conservation properties such as mass and total energy. The baroclinic waves are triggered when overlaying the steady-state initial conditions with the zonal wind perturbation whereas the initial conditions are given as quasi-realistic analytic expressions form. The computational domain is the singularity-free cubed-sphere geometry Time integration follows the third-order SSP-RK scheme. To validate proposed 3D DG model, the baroclinic-instability test suite proposed by Jablonowski and Williamson is investigated. Currently, the 3D DG model performs successfully up to 10-day simulation. The DG discretization uses high-order nodal basis set of Lagrange-Legendrepolynomials and fluxes of interelement boundaries are approximated with Lax-Friedrichs numerical flux. Time step was measured for the main DG time-stepping loop using hardware performance counters for IBM supercomputer. © 2007