The European Geostrophic Wind Reconstruction (EGWR): a 220-year daily record of European geostrophic wind from surface pressure (1806–2026)

Abstract. Spatially consistent European wind observations suitable for continental-scale analysis cover only about four decades, limiting the study of infrequent and prolonged low-wind periods. We present the European Geostrophic Wind Reconstruction (EGWR), a daily record of large-scale geostrophic wind for fourteen European regions from 1806 to 2026. EGWR is derived from surface pressure in Twentieth Century Reanalysis version 3 (20CRv3) for 1806–2015 and from ERA5 thereafter. Sparse early observations smooth the ensemble-mean pressure field and systematically weaken the derived pressure gradient. A temperature-stratified decomposition identifies this as the dominant bias and attributes it to pressure-field smoothing rather than residual barometer calibration error. We correct the bias with a time-varying, region-specific, rank-preserving quantile mapping referenced to the well-observed part of the reconstruction and to ERA5.

The correction restores the wind-amplitude distribution without changing the temporal ordering of the daily record. Independent validation against ERA5, observed German wind-power generation, and two long-term anemometer records shows agreement at daily and multi-day event scales. The released dataset contains the corrected regional series together with uncertainty estimates, source and quality flags, and an optional low-frequency diagnostic. Region-specific recommended start years identify the earliest periods suitable for quantitative persistence statistics. The calibration also acts as an effective 15-year high-pass filter, removing network-driven observational drift. EGWR therefore resolves daily-to-interannual variability and persistence, whereas absolute multidecadal trends require the separately provided low-frequency diagnostic. EGWR provides an observation-based, two-century baseline for studies of European wind variability, persistence, and low-wind events.