Title
High-Resolution Mesh Convergence Properties and Parallel Efficiency of a Spectral Element Atmospheric Dynamical Core
Abstract
We first demonstrate the parallel performance of the dynamical core of a spectral element atmospheric model. The model uses continuous Galerkin spectral elements to discretize the surface of the Earth, coupled with finite differences in the radial direction. Results are presented from two distributed memory, mesh interconnect supercomputers (ASCI Red and BlueGene/L), using a two-dimensional space filling curve domain decomposition. Better than 80% parallel efficiency is obtained for fixed grids on up to 8938 processors. These runs represent the largest processor counts ever achieved for a geophysical application. They show that the upcoming Red Storm and BlueGene/L super-computers are well suited for performing global atmospheric simulations with a 10 km average grid spacing. We then demonstrate the accuracy of the method by performing a full three-dimensional mesh refinement convergence study, using the primitive equations to model breaking Rossby waves on the polar vortex. Due to the excellent parallel performance, the model is run at several resolutions up to 36 km with 200 levels using only modest computing resources. Isosurfaces of scaled potential vorticity exhibit complex dynamical features, e.g. a primary potential vorticity tongue, and a secondary instability causing roll-up into a ring of five smaller subvortices. As the resolution is increased, these features are shown to converge while potential vorticity gradients steepen.
Year
DOI
Venue
2005
10.1177/1094342005056108
IJHPCA
Keywords
Field
DocType
domain decomposition,atmospheric circulation,distributed memory,high resolution,atmospheric modeling
Discretization,Finite difference,Computer science,Parallel computing,Galerkin method,Primitive equations,Instability,Theoretical computer science,Atmospheric model,Potential vorticity,Domain decomposition methods
Journal
Volume
Issue
ISSN
19
3
1094-3420
Citations 
PageRank 
References 
18
1.98
7
Authors
7
Name
Order
Citations
PageRank
John M. Dennis124139.70
Aimé Fournier2586.00
William F. Spotz3263.37
Amik St.-Cyr416313.64
Mark A. Taylor515813.77
Stephen J. Thomas67213.63
Henry M. Tufo711313.95