Nationwide hydrological water budget: focus on drought and natural availability of renewable water resources. Update to 2022.
In the framework of its national operational hydrology activities, the Italian Institute for Environmental Research and Protection has developed a distributed water budget model named BIGBANG – Bilancio Idrologico GIS BAsed a scala Nazionale su Griglia regolare, aimed at evaluating the hydrological water budget components at monthly scale, whose methodology is described in the ISPRA Report n. 339/2021.
Based on the estimates produced by the version 7.0 of the BIGBANG model, this report provides, in a homogeneous hydrological context at national level, a focus on the precipitation deficit and the consequent reduction of natural availability of renewable water resources that characterized the year 2022. As shown in the elaborations reported, in 2022 the country reached an all-time low, from 1951 to today, of annual availability of water resources, a situation also aggravated by above-average temperatures, which increased the amount of evapotranspiration. The report also analyzes the extreme and persistent drought that affected Italy in 2022 and which, in some areas of the territory, already manifested itself at the end of 2021 and lasted until the first months of 2023. The analyzes show that, if the percentage of national territory that was subject to extreme drought during the same year is considered as an indicator of drought severity, 2022 was the sixth driest year in Italy since 1952.
Publication available only on-line