QuikSCAT Satellite Comparisons with Nearshore Buoy Wind Data off the U.S. West Coast

Abstract

To determine the accuracy of nearshore winds from the QuikSCAT satellite, winds from three satellite datasets (scientifically processed swath, gridded near-real-time, and gridded science datasets) were compared to those from 12 nearshore and 3 offshore U.S. West Coast buoys. Satellite observations from August 1999 to December 2000 that were within 25 km and 30 min of each buoy were used. Comparisons showed that satellite–buoy wind differences near shore were larger than those offshore. Editing the satellite data by discarding observations recorded in rain and those recorded in light winds improved the accuracy of all three datasets. After removing rain-flagged data and wind speeds less than 3 m s−1, root-mean-squared differences (satellite minus buoy) for swath data, the best of the three datasets, were 1.4 m s−1 and 37° based on 5741 nearshore comparisons. By removing winds less than 6 m s−1, these differences were reduced to 1.3 m s−1 and 26°. At the three offshore buoys, the root-mean-squared differences for the swath data, with both rain and winds less than 6 m s−1 removed, were 1.0 m s−1 and 15° based on 1920 comparisons. Although the satellite's scientifically processed swath data near shore do not match buoy observations as closely as those offshore, they are sufficiently accurate for many coastal studies.