A new daily high-resolution gridded precipitation dataset for the Italian Greater Alpine Region (1951–2023): spatio-temporal analysis and hydrological applications

Study region Italian Hydrological part of the Greater Alpine Region. Study focus Setting up a daily high-resolution gridded precipitation dataset over the 1951–2023 period using 7417 quality-checked meteorological stations. It is mainly based on the Italian networks of mechanical and automatic stations, and it has been used to obtain 7.5 arc-second resolution (about 230 m) daily fields by means of the anomaly method. The gridded fields are available at 30 arc-second-resolution at https://doi.org/10.13130/RD_UNIMI/CSYYAP. New insights for the region The monthly 1991–2020 high-resolution climatologies, obtained interpolating the stations by means of a Local Weighted Linear Regression of precipitation versus elevation, range, at annual level, from 521 mm to 3021 mm. The temporal evolution of the relative anomaly series, with respect to the 1991–2020 period, does not show any significant trend, except for summer (about −3% per decade – p-value ≤ 0.05). The obtained fields can be used to reconstruct any precipitation event in the investigated area and period. Together with corresponding temperature fields, they were fed into the Poly-Hydro hydrological model to estimate the runoff series for the Adda River and the Toce River. The resulting series showed an excellent agreement with the corresponding observational series. The slightly underestimation of the model (about 6.3% for the Adda and 5.8% for the Toce) seems to be due to the underestimation of rain gauges of solid precipitation.