Comparison between weather buoy and Comprehensive Ocean‐Atmosphere Data Set wind data for the west coast of Canada

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Abstract
We describe surface wind data from Canadian weather buoys in the northeast Pacific and compare monthly mean wind speed and direction during 1987 to 1992 from these buoys with monthly mean values in the Comprehensive Ocean‐Atmosphere Data Set (COADS). The latter is based mainly on data from volunteer observing ships (VOS), binned in 2° × 2° squares. The number of VOS observations in each square in Hecate Strait, Dixon Entrance, and Queen Charlotte Sound is too low to produce reliable averages. Near other buoys we find COADS wind speeds to be higher than buoy wind speeds by about 1 to 2 m s−1. This difference shows some dependence on wind speed and is in qualitative agreement with previous comparisons between VOS and weather buoy winds. In addition, we find direction‐dependent differences in wind direction, with COADS wind vectors to the right of buoy wind vectors for alongshore winds from the northwest near the Vancouver Island coast. These results suggest that high placement of anemometers (above 25–30 m) on large modern vessels is partly responsible for higher COADS wind speeds, while rotation of wind vectors along mountain ranges and inadequate VOS coverage in coastal waters is biasing wind direction in COADS data toward the open ocean winds.