An unstructured-mesh atmospheric model for nonhydrostatic dynamics: towards optimal mesh resolution
journal contributionposted on 15.07.2015, 13:54 by Joanna Szmelter, Zhao Zhang, Piotr K. Smolarkiewicz
The paper advances the limited-area anelastic model (Smolarkiewicz et al. (2013) ) for investigation of nonhydrostatic dynamics in mesoscale atmospheric flows. New developments include the extension to a tetrahedral-based median-dual option for unstructured meshes and a static mesh adaptivity technique using an error indicator based on inherent properties of the Multidimensional Positive Definite Advection Transport Algorithm (MPDATA). The model employs semi-implicit nonoscillatory forward-in-time integrators for soundproof PDEs, built on MPDATA and a robust non-symmetric Krylov-subspace elliptic solver. Finite-volume spatial discretisation adopts an edge-based data structure. Simulations of stratified orographic flows and the associated gravity-wave phenomena in media with uniform and variable dispersive properties verify the advancement and demonstrate the potential of heterogeneous anisotropic discretisation with large variation in spatial resolution for study of complex stratified flows that can be computationally unattainable with regular grids.
The authors acknowledge support by the NERC/G004358 award and funding received from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2012/ERC Grant agreement No.320375).
- Mechanical, Electrical and Manufacturing Engineering