Wind Speed Evaluation of MERRA-2, ERA-Interim and ERA-5 Reanalysis Data at a Wind Farm Located in Brazil
Abstract
Climatological normal is a powerful tool to understand the behavior of meteorological variables like wind speeds and it is typically employed in wind resource assessments. This paper compares two different sources of long-term wind speed data at a wind farm in Northeast Brazil to meteorological mast observations performed at the site from 2009 to 2018. The main goal is to determine which one better describes the wind climate at the wind farm site. Both sources, ERA-Interim and MERRA-2, showed satisfactory correlations for monthly means when compared with meteorological mast data, which are 0.94 and 0.91, respectively. Biases were -4.5 and -0.16, respectively. Although the wind speed observations were systematically underestimated, both reanalysis databases represented the seasonal variability properly. The negative bias values can be reduced by employing a vertical extrapolation, considering that the observations heights differs from wind farm site to both reanalysis.