On the Use of QuikSCAT Scatterometer Measurements of Surface Winds for Marine Weather Prediction

The value of Quick Scatterometer (QuikSCAT) measurements of 10-m ocean vector winds for marineweather prediction is investigated from two Northern Hemisphere case studies. The first of these focuses onan intense cyclone with hurricane-force winds that occurred over the extratropical western North Pacific on10 January 2005. The second is a 17 February 2005 example that is typical of sea surface temperatureinfluence on low-level winds in moderate wind conditions in the vicinity of the Gulf Stream in the westernNorth Atlantic. In both cases, the analyses of 10-m winds from the NCEP and ECMWF global numericalweather prediction models considerably underestimated the spatial variability of the wind field on scalessmaller than 1000 km compared with the structure determined from QuikSCAT observations. The NCEPand ECMWF models both assimilate QuikSCAT observations. While the accuracies of the 10-m windanalyses from these models measurably improved after implementation of the QuikSCAT data assimilation,the information content in the QuikSCAT data is underutilized by the numerical models. QuikSCAT dataare available in near–real time in the NOAA/NCEP Advanced Weather Interactive Processing System(N-AWIPS) and are used extensively in manual analyses of surface winds. The high resolution of theQuikSCAT data is routinely utilized by forecasters at the NOAA/NCEP Ocean Prediction Center, TropicalPrediction Center, and other NOAA weather forecast offices to improve the accuracies of wind warningsin marine forecasts.

This researchwas supported by NASA Grant NAS5-32965 forfunding of Ocean Vector Winds Science Team activities,Award NA03NES4400001, to Oregon State Universityfrom the National Oceanic and AtmosphericAdministration, U.S. Department of Commerce, andby the National Oceanographic Partnership Programfunding under Scatterometer-Derived OperationalWinds, Surface Pressures, and Rain through theNOAA/National Environmental Satellite, Data, andInformation Service (NESDIS).