NMMB developments: radiation, mineral dust and chemistry

Carlos Perez
EMC Visiting Scientist


The NMMB atmospheric model developed at the EMC is an evolution of the operational WRF-NMME model extending from meso to global scales. Its unified non-hydrostatic dynamical core allows regional and global simulations. The Barcelona Supercomputing Center (BSC) has developed a new atmospheric mineral dust model (BSC-Dust) coupled on-line to the NMMB, representing the first step towards the implementation on-line of a full chemistry transport model. The new modeling system is intended to be a powerful tool for research and to provide efficient chemical weather forecasts at sub-synoptic and mesoscale resolutions.

Within the collaboration between EMC and BSC, the RRTM radiation has been coupled to the NMMB model and the initial steps were undertaken for diagnosing and improving the efficiency of the model on high performance supercomputers.

The seminar will mainly summarize and discuss the results obtained with the NMMB-RRTM in terms of biases, rms and anomaly correlations at a global scale. The NMMB-RRTM is now fully functional and already shows significant benefits in comparison to GFDL radiation. The radiation module allows the choice of different albedos, aerosol climatologies (OPAC, GOCART) and on-line aerosol (BSC-Dust). The main effort was devoted to investigate the response of the model to different treatments of clouds (stratiform and convective) and their optical properties. Finally we will formulate some recommendations for future work and further refinement of the NMMB-RRTM.