Error Estimates for Ocean Surface Winds: Applying Desroziers Diagnostics to the Cross-Calibrated, Multiplatform Analysis of Wind Speed

Abstract

he Desroziers diagnostics (DD) are applied to the cross-calibrated, multiplatform (CCMP) ocean surface wind datasets to estimate wind speed errors of the ECMWF background, the microwave satellite observations, and the resulting CCMP analysis. The DD confirm that the ECMWF operational surface wind speed error standard deviations vary with latitude in the range 0.8?1.3 m s?1 and that the cross-calibrated Remote Sensing Systems (RSS) wind speed retrievals? standard deviations are in the range 0.5?0.7 m s?1. Further, the estimated CCMP analysis wind speed standard deviations are in the range 0.2?0.3 m s?1. The results suggest the need to revise the parameterization of the errors of the first guess at appropriate time (FGAT) procedure. Errors for wind speeds <16 m s?1 are homogeneous; however, for the relatively rare but critical higher wind speed situations, errors are much larger.