Regional Mountain Conference

We present a 75-year, 500 m resolution reanalysis of Snow Water Equivalent (SWE) across the European Alps (1950–2025). The dataset was developed in the context of the A-DROP – Alpine DROught Prediction INTERREG Alpine Space project (https://www.alpine-space.eu/project/a-drop/) and is driven by ERA5-Land meteorological reanalysis downscaled to 500 m using the MicroMet statistical–dynamical method (Liston and Elder, 2006). Downscaled meteorological fields are used to force the physically-based S3M snow model (Avanzi et al., 2022). Our reanalysis covers the full Alpine domain, providing the first high-resolution, spatially consistent, open-source SWE dataset for the region. Validation against in situ measurements (Matiu et al., 2021) demonstrates robust performance across all elevations. The dataset captures long-term SWE variability and trends over the past seven decades. It enables comprehensive analyses of snowpack dynamics and hydrological modeling in Alpine environments. All outputs are openly accessible and will be dynamically updated annually. This work provides a critical resource for climate, hydrology, and mountain ecosystem studies in the European Alps.