Development of the next generation SLAV global atmospheric model
SLAV is the global finite-difference semi-Lagrangian numerical weather prediction model used operationally at Hydrometcentre of Russia. Its features are the use of vorticity-divergence formulation (in horizontal plane) on the unstaggered grid and 4th-order finite differences. The current version in work has the resolution of (0.18-0.22) degrees in latitude, 0.225 degrees in longitude, 51 levels. The presentation covers two topics: 1. Further development of the existing hydrostatic version. This includes: - Implementation of the mass-conserving semi-Lagrangian advection on the reduced lat-lon grid. This is a 3D extension of (Tolstykh, Shashkin, JCP 2012). Some preliminary results will be shown. - Recent increase of code scalability from 160 to more than 800 cores. - Work on further increase of scalability. 2. Plans for development of the global nonhydrostatic model. We plan to test a parallel elliptic solver (the code developed at INM) on different massively parallel platforms with a matrix arising in the semi-implicit discretization of MC2-type nonhydrostatic model formulation. Depending on the results, we will choose between the semi-implicit and horizontally explicit-vertically implicit (HE-VI) time integration schemes. The potential choice of HE-VI would imply the radical changes in the next generation of our dynamical core. These changes will be also discussed in the presentation.