Search

The ISPRA (Italian National Institute for Environmental Protection and Research) has developed a GIS based procedure (BIGBANG 1.0—“Nationwide GIS-based hydrological water budget on a regular grid”) for evaluating all the factors of the monthly groundwater balance at National scale, using Python programming language. The procedure is based on spatial environmental information at very high resolution, often available on the WEB, in formats easily usable by the main geographic information systems. The hydrological factors of total precipitation, actual evapotranspiration, surface runoff and aquifer recharge are evaluated for a grid of 1 km resolution. The tool has been applied to the Campania Region (southern Italy) for the period 1996–2015, also defining for all factors the LTAA (Long Term Annual Average). These results and the monthly evaluations have been compared with groundwater balances carried out at local scale, in a carbonate groundwater body. The comparison shows that the lithological and hydrogeological features, much more detailed at local scale, can influence some factors of the balance, but the final amount of the recharge is comparable. Finally, this comparison, apart the above cited observations, represents a valid test for the BIGBANG 1.0 procedure and for its future implementation in the next versions.

The present study investigates the impact of climate change on the availability of groundwater resources in Italy and in Campania region (Southern Italy). A 20-year average from 1996 to 2015 of annual water budget components (namely total precipitation, actual evapotranspiration, surface runoff and aquifer recharge) has been evaluated over a 1-km resolution grid and have been projected considering four climate change scenarios (from the Fifth Assessment Report of the United Nations Intergovernmental Panel on Climate Change) and three different future 20-year time periods (2020–2039, 2040–2059 and 2080–2099). The groundwater balance has been carried out on a yearly basis using the “Nationwide GIS-based regular gridded hydrological water budget” procedure, which has been developed by the Italian National Institute for Environmental Protection and Research (ISPRA). The different scenarios of groundwater resources have been compared and matched to the 20-year average of latest historical values related to the period 1996–2015, leading to interesting considerations about the future depletion of groundwater resources. Nationwide results have been compared with those of Campania region, in order to underline the significant differences of climate change impact on groundwater resources at local scale, especially in a typical Mediterranean climate where groundwater resources represent the main source of water for human needs.

The rainfall monitoring network of the Naples Department of Hydrographic and Oceanographic Service (NDHOS) was inadequate to measure the alluvial event occurred at Sarno on 5 May 1998, when a low rainfall amount of 101 mm was considered responsible for a dramatic landslide. To improve the measuring capability of this network, 50 new monitoring stations were later on added and located in such a way to increase significantly the fractal dimension of their areal distribution. The enlargement of the network allowed the correct measurement of the extreme event occurred in Naples on 15 September 2001. The paper reports also the risk of landslide phenomena (not catastrophic but however not negligible) inside the metropolitan area of Naples, frequently subjected to rock falls and to collapse of underground cavities.