Presentations

Abstract

The European Centre for Medium-Range Weather Forecasts (ECMWF) is advancing atmospheric reanalysis with the release of ERA6. To date, two data batches have been released: a 3-month set and a subsequent 7-month set. At Vortex, we have dynamically downscaled the complete 3D ERA6 dataset using in-depth WRF simulations to a 3 km horizontal grid with hourly resolution. We compared the resulting wind fields to equivalent simulations using ERA5 reanalysis across more than 1,000 global locations of interest to the wind energy industry. For a subset of these locations, where quality-controlled observations are available, we conducted detailed validation analyses. Given the limited dataset duration, our analysis focused primarily on hourly and daily metrics. Preliminary results indicate that ERA6 shows modest improvements in correlation metrics, with an average global increase of 1% for both hourly and daily timescales. Bias deviations remain largely unchanged compared to ERA5. Beyond global metrics, we performed a country-level aggregation, revealing regional trends: correlation metrics improved in over 60% of the 40 countries analyzed, with some countries showing increases of up to 8%. Conversely, a smaller subset of countries experienced declines of up to 8% in correlation. These findings highlight both the potential benefits and limitations of ERA6 for wind resource assessment. While ERA6 demonstrates improved representation in certain regions, the limited dataset duration and lack of significant bias improvement compared to ERA5 suggest that caution is needed when generalizing these results. Moreover, the increased data volume and storage requirements associated with ERA6 present practical challenges for its adoption in operational workflows. This presentation will detail our methodological approach, the innovations introduced in data processing and validation, and a regional analysis of ERA6’s performance. By providing a first assessment of ERA6 in real-world wind resource applications, we aim to offer valuable guidance to the wind energy community as it prepares to transition to this new reanalysis standard.