The fifth generation regional climate modeling system RegCM5: Description and model validation over all CORDEX domains at hydrostatic and conveciton-permitting resolutions

A new limited area model able to perform at a broad resolution range spanning from hydrostatic to convection permitting resolution  was needed to serve the big RegCM community when exploring the new frontiers of the regional climate modelling science . For this purpose the new RegCM5 non-hydrostatic core has been implemented. The new core  solves the dynamical equations by using a Weighted Average Flux (WAF) advection scheme with implicit vertical sound waves propagation, discretized on a horizontal Arakawa C-grid with terrain following hybrid height coordinate and Euler time integration, using split time-steps for both advection and vertical sound waves. No explicit diffusion is included except for a divergence damping. The model physical packages are adapted from the RegCM4. RegCM5 has been fully tested on all the CORDEX-CORE domain and in several convection permitting domains already used with the previous model version. The model integration time is on average four time faster compared to the previous version given that a larger time step is allowed for the integration. The RegCM5 results have been compared with the previous CORDEX-CORE simulations to assess the model ability in reproducing the regional climate in all the world regions and improvements in model statistics have been founds in several domains.