EMO-1: an improved version of the high-resolution multi-variable gridded meteorological dataset for Europe

Abstract. High-quality, gridded meteorological datasets are essential for continental-scale hydrological modelling. This paper introduces EMO-1, an advanced version of the European Meteorological Observations (EMO) dataset, developed to support the operational European Flood Awareness System (EFAS) of the Copernicus Emergency Management Service. EMO-1 provides daily and 6-hourly meteorological fields across Europe at a high spatial resolution of 1 arc-minute (~1.5 km) covering the period from 1990 to 2024. The dataset represents a substantial upgrade over its predecessor, EMO-5, integrating observations from 47 data providers and increasing significantly the number of stations used for interpolation. It harmonizes heterogeneous data from in-situ stations and integrates "virtual stations" from high-resolution regional grids and ERA5-Land to minimize data gaps in regions with very low station density. The dataset covers eight variables: daily and 6-hourly total precipitation, minimum and maximum air temperature, 6-hourly average air temperature, daily mean wind speed, solar radiation, and water vapor pressure. A rigorous, two-tier quality control system is applied to filter erroneous observations before processing. For interpolation EMO-1 uses an open-source implementation of the Angular Distance Weighting (ADW) scheme. Cross-validation results demonstrate that ADW maintains interpolation skill comparable to other deterministic methods while offering superior computational efficiency and reproducibility. EMO-1 prioritizes station density and timeliness to serve operational forecasting needs, although the resulting spatial-temporal heterogeneity makes it less suitable for long-term trend analysis. The dataset is openly available under a Creative Commons Attribution 4.0 license via the Joint Research Centre Data Catalogue, with foreseen annual updates and accessible open-source interpolation software to foster transparency and community collaboration.