Model Characteristics

The COSMO Model ( a non hydrostatic limited-area atmospheric prediction model. It has been designed for both operational numerical weather prediction (NWP) and various scientific applications on the meso-β and meso-γ scale.

The COSMO Model is based on the primitive thermo-hydrodynamical equations describing compressible flow in a moist atmosphere. The model equations are formulated in rotated geographical coordinates and a generalized terrain following height coordinate. A variety of physical processes are taken into account by parameterization schemes. Besides the forecast model itself, a number of additional components such as data assimilation, interpolation of boundary conditions from a driving model, and postprocessing utilities are required to run the model in NWPmode, climate mode or for case studies.

Regional numerical weather prediction at COMET is entirely based on the COSMO Model. COSMO-ME covers Europe with 1083x559 grid points/layer at a grid spacing of 5 km and 45 layers, and the convection-resolving model COSMO-IT, covers Italy and its surroundings with a grid spacing of 2.8 km, 542x604 grid points/layer and 65 layers. Based on COSMO-ME, a probabilistic ensemble prediction system on the convective scale, called COSMO-ME-EPS, became operational with 40 EPS members on 2015. It is based on COSMO-ME with a grid spacing of 7 km, 779x401 grid points/layer and 45 layers.

Documentation is fully available at