Comparison of wind data from ERA-Interim and buoys in the Yellow and East China Seas

We compared data of sea surface wind from the European Centre for Medium-Range Weather Forecasts Interim Reanalysis (ERA-Interim) with that collected from eight buoys deployed in the Yellow and East China seas. The buoy data covered a period from 2010 to 2011, during which the longest time series without missing data extended for 329 days. Results show that the ERA-Interim wind data agree well with the buoy data. The regression coefficients between the ERA-Interim and observed wind speed and direction are greater than 0.7 and 0.79, respectively. However, the ERA-Interim wind data overestimate wind speed at most of the buoy stations, for which the largest bias is 1.8 m/s. Moreover, it is found from scatter plots of wind direction that about 13% of the ERA-Interim wind data can be classified as bad for wind speeds below 6 m/s. Overall, the ERA-Interim data forecast both the wind speed and direction well, although they are not very representative of our observations, especially those where the wind speed is below 6 m/s.