To assess the quality of the information provided by 3TIER’s global wind dataset, wind speeds were compared with publicly available wind speed observations from the independent data source, National Centers for Environmental Prediction (NCEP) Automated Data Processing (ADP) surface observations dataset. The stations with 4-letter ICAO location indicators were chosen from the subset of NCEP-ADP stations, because they have more reliable data than other stations in the dataset.

Time-series data from these stations were visually inspected, and stations with obvious data problems were excluded from the validation. The NCEP-ADP wind speeds were compared with wind speeds from 3TIER’s global wind dataset at a height of 10 m. While it is likely that some NCEP-ADP station anemometers are at heights lower than 10 m, few are expected to be higher than 10 m. This method was used consistently across every region solely for validation purposes and observations were not used to adjust data shown by the Wind Prospecting Tools in any way. In the final comparison with actual NCEP-ADP direct observations, the annual mean wind speeds provided by 3TIER’s global wind dataset have a difference of less than 0.5 m/s for 50% of stations and a difference of less than 1 m/s for 78% of stations. The overall bias is +0.05 m/s relative to NCEP-ADP observations, and the RMSE (Root Mean Squared Error) is 0.93 m/s.

For additional information, please see 3TIER's global wind validation white paper.