Calibrating the Microphysics of the RAMS Model

This paper presents curve adjustments for the droplet spectra measured by the FSSP probe, as well as sensitivity tests for the RAMS 6.0 model, in its cloud microphysics module, in order to obtain a better configuration of this model for the State of Ceará, Brazil. The methodology used is based on comparisons between the model results and observations collected through the Cloud Microphysics Experiment (EMfiN!), conducted in the city of Fortaleza, Ceará, Brazil, from 1 to 12 April 2002. Sensitivity simulations were performed by altering the concentration of cloud droplets and the shape parameter of the gamma distribution. The objective is to find an appropriate configuration for local conditions and, consequently, a better representation of the behaviour of convective systems over the state of Ceará, Brazil. To compare the results of the simulations with reality, meteorological radar images collected during EMfiN! were used.