Long term trends and variability of observed winds from operational meteorology - (PPT)

摘要

To estimate future wind resources available at a location there is a need to account for the likely variation due to interannual and longer term variations over the lifetime of the wind farm. The current practise has been based on estimates of the interannual variation from 10m wind observations used in operational meteorology. These studies are several years old and here a new look is taken at comprehensive datasets from around the globe collected by meteorological and climatological services. The oft quoted 6% annual variation of wind speed is critically re-evaluated. Well-maintained long-term conventional meteorological observations are examined, including surface (10m) winds and upper air winds from radiosondes. We attempt to differentiate between trends which have observational support and likely spurious ones due to changes in observing site location and/or exposure.