THE SCATTEROMETER AS A PRESSURE SENSOR

Abstract

The UW Planetary Boundary Layer (PBL) model is used to derive surface pressure fields from scatterometer surface measurements. After a decade of comparison with NMC wind products, it is clear that the combination of the scatterometer and the PBL model yield superior information about the global pressure fields. The pressure fields are used to correct the scatterometer winds where they are contaminated by rain or poorly retrieved due to antenna geometry. The new winds are compared to buoy wind measurements. The scatterometer-derived surface pressure fields are assessed with buoy measurements and NWS analyses (NCEP, ECMWF and MM5 in the Gulf of Alaska). The gradients are systematically compared to buoy-measured pressure gradients. The model has been used to initialize a GCM with Geostrophic (pressure gradient) winds, yielding superior prognoses to initialization with surface winds. Original and corrected scatterometer winds are being assimilated in a NWF model.