On the occasion of the celebration of World Water Day, ISPRA intends to present the 2025 update of the estimates of the components of the hydrological balance and the natural availability of renewable water resources provided by the BIGBANG model – GIS-Based Hydrological Balance at the National Scale on a Regular Grid. The presentation will also include assessments of the 2025 drought conditions and long-term hydro-climatic statistics.

The BIGBANG assessments at the national and river basin district scale for total precipitation, evapotranspiration, aquifer recharge, and water resource availability (the so-called “internal flow”) constitute the official national data for the WISE SoE – Water Quantity (WISE-3) data flow and for the evaluation of the Water Exploitation Index Plus (WEI+), within the framework of the Water Framework Directive 2000/60/EC, as well as for the reporting requirements of the OECD/Eurostat Joint Questionnaire on Inland Waters.

Furthermore, starting from the National Statistical Programme 2023–2025, the National Hydrological Balance indicators produced through the BIGBANG model constitute official statistics within SISTAN – the National Statistical System.

The Workshop is part of ISPRA’s national activities on hydrological characterization and will also provide an opportunity to present the new seasonal forecasting service for hydrological balance and water availability developed by the Institute within the Italian initiative for the National Collaboration Programme (NCP) of the Copernicus Climate Change Service (C3S), promoted by the ECMWF – European Centre for Medium-Range Weather Forecasts, which operates the Copernicus Service on behalf of the European Union.

In addition, future estimates based on climate projections of surface runoff, aquifer recharge, and water resource availability will be presented, also with a view to assessing hydropower production.

During the morning session, application examples of the BIGBANG products will be presented, ranging from the national scale to the local scale.

In-person participation in the Workshop requires registration for the event and will be possible until the maximum number of available seats in the venue is reached.

Program