Global Semi-Lagrangian Atmospheric Model Based on Compact Finite-Differences and its Implementation on a Parallel Computer
Abstract
The semi-Lagrangian atmospheric model on the sphere based on compact finite differences is presented. In the two-dimensional case, the potential vorticity is used as one of the prognostic variables. Fourth-order compact finite differences are used to discretize first- and second-order derivatives. The results including real data tests presented for 2D shallow water version with orography demonstrate its accuracy with the time steps several times greater than in Eulerian model. The 3D version of the model uses the absolute vorticity equation. Some results including a real data forecast are presented. The parallel implementation of the 3D model on a distributed memory parallel computer is described