Modifying the conventional three-time-level semi-implicit semi-Lagrangian scheme to eliminate orographically-induced spurious resonance

Rivest, C., and A. Staniforth
Recherche en prévision numérique
2121 Route Transcanadienne, porte 500
Dorval, Québec
 CANADA H9P 1J3

 
 

 ABSTRACT

Three-time-level semi-implicit semi-Lagrangian discretizations are used in many meteorological centres around the world. Following the work of Rivers et al. (1994) on two-time-level schemes, it is essential to modify existing three-time-level schemes to avoid orographically induced spurious resonance. A four-time-level scheme targeted as a rapidly implemented retrofit for the conventional three-time-level scheme, is proposed, analysed, and evaluated in the context of the shallow-water equations.