WRF-ARW sensitivity to different planetary boundary layer parameterization over South America

RUIZ JUAN; FERREIRA LORENA; SAULO ANDREA CELESTE

WGNE Blue book

Año: 2007 p. 11 - 13

The WRF-ARW (Advanced Research- Weather Research and Forecasting) model has been implemented at CIMA (Centro de Investigaciones del Mar y la Atmósfera) since November 2005, to provide operative short range, mesoscale weather forecasts over South America (http://wrf.cima.fcen.uba.ar). Since then, some studies (Ruiz and Saulo, 2006) have been devoted to evaluate WRF performance over South America since there is almost no documentation about its performance over this particular region Preliminary analysis of these operational forecasts, show that forecasted surface temperatures are lower than the observed values. This systematic bias could be caused by several reasons, e.g. misrepresentation of heat fluxes at the surface or limitations in the Planetary Boundary Layer parameterization (PBL). In order to address the deficiencies in the representation of temperature at low levels, we report here the results obtained from the analysis of model sensitivity to the use of two different planetary boundary layer (PBL) parameterizations, which are provided with the WRF-ARW code.