see also:
basic design 
initial and boundary conditions 
physical parameterizations 
external parameters 
code and parallelization 
data assimilation
Last updated: September 2011
The COSMOModel is based on the primitive hydrothermodynamical equations describing compressible nonhydrostatic flow in a moist atmosphere without any scale approximations. A basic state is subtracted from the equations to reduce numerical errors associated with the calculation of the pressure gradient force in case of sloping coordinate surfaces. The basic state represents a timeindependent dry atmosphere at rest which is prescribed to be horizontally homogeneous, vertically stratified and in hydrostatic balance.
The basic equations are written in advection form and the continuity equation is replaced by a prognostic equation for the perturbation pressure (i.e. the deviation of pressure from the reference state). The model equations are solved numerically using the traditional finite difference method. In the following we summarize the dynamical and numerical key features of the COSMOModel.
Model Equations 


Prognostic Variables 

Diagnostic Variables 

Coordinate System 

Grid Structure 

Spatial Discretization 

Time Integration  Default scheme:

Numerical Smoothing 
