P-19

Observing System Experiment in the CPTEC/INPE 3D-Var data assimilation system

H. Azevedo (CPTEC/INPE), and L.G. de Goncalves (CPTEC/INPE)

Techniques for evaluating the impact of observations in data assimilation systems have been increasingly enhanced, however one of the oldest, most widely used and efficient, the Observing System Experiments, has been used to date. Using this technique, three experiments were performed: without radiances data, without GPS data and without radiosonde data. Results from these experiments were compared with the control experiment, which uses all the available data. These experiments were carried out for January 2013, using the G3DVAR, which system uses GSI coupled to General Circulation Model (GCM) of the CPTEC/INPE in the T299L64 resolution. Were evaluated the Globe, Southern Hemisphere, Northern Hemisphere and South America through the geopotential height at 500hPa and the Tropical region through wind 850hPa and 250hPa. With this work may be noted the importance of satellite data for any region in particular regions located in the Southern Hemisphere.