Evapotranspiration estimates and associated climate variables in the high-altitude grasslands of the Nivolet Plain, Gran Paradiso National Park, Italy, 2020-2023

This dataset presents quantitative Evapotranspiration flux data (ET) from a high-mountain grassland in the Nivolet Plain, Gran Paradiso National Park (north-western Italian Alps, where a Critical Zone Observatory (CZO@NIVOLET) was established in 2017, and where several CO₂ flux measurement campaigns have been conducted (Magnani et al., 2020; Lenzi et al., 2023; Vivaldo et al., 2023; Parisi et al., 2024; Marta et al., 2026). In Alpine areas, ET plays an important role in grassland dynamics, having been studied either through modelling approaches or by measuring evaporating bodies. The water flux measurements presented here provide direct field information on flux magnitude and influencing factors, supported by simultaneous measurements of climatic and environmental variables. This dataset is intended for use as input and/or validation data in hydrological and ecohydrological models at fine and intermediate scales. The dataset is provided as a single comma-separated values (CSV) file containing the following variables: Variable Description Units DATE_TIME Date and time of measurement in ISO format YYYY-MM-DDTHH:MM:SSZ where time is CEST (UTC+2) YYYY-MM-DDTHH:MM:SSZ YEAR Year of measurement YYYY DATE Date of measurement YYYY-MM-DD HOUR Hour of measurement in CEST (UTC+2) hh:mm:ss DOY Day of Year (1-365) - SITE_ID Site identifier (AL, GL, GN) - rs Solar irradiance W m⁻² Air_temperature Air temperature °C RH Air relative humidity % Atmospheric_pressure Atmospheric pressure hPa Soil_temperature Soil temperature at 10 cm °C Volumetric Water Content Soil volumetric water content at 5 cm % ET Evapotranspiration flux mmol H₂O m⁻² s⁻¹ References cited above are: Lenzi, S. et al. (2023) ‘Spatial and temporal variability of carbon dioxide fluxes in the Alpine Critical Zone: The case of the Nivolet Plain, Gran Paradiso National Park, Italy’, PLoS ONE, 18(5), e0286268. https://doi.org/10.1371/journal.pone.0286268 Magnani, M. et al. (2020) ‘Drivers of carbon fluxes in Alpine tundra: a comparison of three empirical model approaches’, Science of the Total Environment, 732. Available at: https://doi.org/10.1016/j.scitotenv.2020.139139. Marta, S. et al. (2026). ‘Climate Controls on Carbon Dioxide Fluxes in a High-Elevation Grassland’, Global Change Biology Communications, 1, e70016, https://doi.org/10.1002/gcb4.70016 Parisi, A. et al. (2024) ‘Carbon dioxide fluxes in Alpine grasslands at the Nivolet Plain, Gran Paradiso National Park, Italy 2017–2023’, Scientific Data, 11, 652. Available at: https://doi.org/10.1038/s41597-024-03374-1 Vivaldo, G. et al. (2023) ‘Carbon dioxide exchanges in an alpine tundra ecosystem (Gran Paradiso National Park, Italy): A comparison of results from different measurement and modelling approaches’, Atmospheric Environment, 305, 119758. Available at: https://doi.org/10.1016/j.atmosenv.2023.119758