Comparison of ERA5 surface wind speed climatologies over Europe with observations from the HadISD dataset
International Journal of Climatology, (March 2021)DOI: 10.1002/joc.7103
Abstract
Understanding space–time features of wind speed is of high interest in meteorology and several applied sciences. Accurate wind speed measurements in combination with reliable gridded products, such as reanalyses, are needed to address the main characteristics of the wind field. Hourly 10 m wind speed from the European Centre for Medium‐Range Weather Forecasts (ECMWF) latest reanalysis (ERA5) is compared with HadISD wind observations from 245 stations across Europe. Averaged ERA5 hourly data is able to reproduce the annual cycle of monthly wind speed in Europe. ERA5 presents slightly larger (shorter) monthly medians in winter (summer) than observations. ERA5 is compared against observations for each station using a frequency distribution‐based score (score, from 0 to 1). Most of the stations exhibit hourly scores ranging from 0.8 to 0.9, indicating that ERA5 is able to reproduce the wind speed spectrum range, from light to strong relative frequencies, for any location over Europe. Ranges of mean values, variability, distribution function parameters and high or low wind thresholds frequencies are shown for this ensemble of European stations, allowing for an overall description of wind features. Generally, there is no clear relationship between scores and the variables analysed. The correlation and scores between ERA5 and HadISD is even further increased at longer time frequencies (6–24 hourly), together with centred root‐mean‐square error (RMSE) and standard deviation decreases. Hourly wind data from ERA5 reanalysis is, despite some shortcomings, valuable information to perform further detailed studies with a regular spatial and time wind distribution, from the climatological or renewable energy perspectives, for example.