GUEDES, M. J. F.; http://lattes.cnpq.br/5145964107339166; GUEDES, Maria Joseane Felipe.
Resumo:
This study investigates the sensitivity of the model "Brazilian Regional
Atmospheric Modeling System" - BRAMS to the several different kinds of closure
associated to the convective parameterization of Grell and to the standard BRAMS
convective parameterization, a Kuo-type cumulus parameterization scheme. The purpose is
to evaluate which scheme gives BRAMS a better performance in the tropical region. The
sensitivity of each closure to horizontal resolution is also studied through experiments with
resolutions of 80 and 20 km. The results are based on 96-hour simulations starting at 00
UTC of 20 January 1999 for Rondonia (Brazil). The data are from the Large-Scale
Biosphere Atmosphere (LBA),
It is shown that the convective parameterizations resulted in a wide variety
of rainfall behaviors during the simulation and that the Kuo scheme showed much smaller
values of precipitation than those observed. The Arakawa-Schubert closure showed good
agreement with the observed values of the surface latent heat flux. Finally the moisture
convergence and Grell closures showed the best results (smaller sensitivity) when the
model's horizontal resolution varies.