The effects of the variations in sea surface temperature and atmospheric stability in the estimation of average wind speed by SEASAT-SASS

Abstract Wind speeds from the scatterometer (SASS) on the ocean observing satellite SEASAT averaged over 2° latitude by 2° longitude and a 92-day period are compared with wind speeds from ship reports in the western North Atlantic and the eastern North Pacific, where the concentrations of ship reports are high and the ranges of atmospheric stability and sea surface temperature are large. The comparison results are consistent for each region and for the combined data. Scatterometer winds are found to be generally higher than ship winds. The systematic dependence of the difference between scatterometer winds and ship winds on sea surface temperature and atmospheric stability are identified. The quality of ship reports is not ideal but should not depend on atmospheric stability or sea surface temperature. The systematic dependences, therefore may reflect the characteristics of scatterometer winds. Multivariate regressions are used to extract the independent effects of different factors on the wind speed diff...