Climate extreme scenarios affecting the Italian energy system with a multi-hazard approach

Abstract The operation of the energy system can be compromised by extreme weather events that can impact generation, transmission and distribution infrastructure, as well as energy demand, and will face even more critical situations in the coming decades due to ongoing climate change. The challenge concerns particularly the infrastructures with long technical life. To support decision makers in planning adaptation actions for increasing the resilience of the Italian Energy System, some analyses about the expected meteorological threats over Italy have been carried out. The study aims to identify the Italian regions more prone to climate extremes at short- (2021–2050), medium- (2041–2070) and long-term (2071–2100) by using 12 high-resolution Euro-CORDEX models under the emission pathways RCP8.5, RCP4.5 and RCP2.6. For this purpose, a subset of the WMO ETCCDI indices was used. In addition, a multi-hazard analysis was carried out by defining the three indices DRO, STO, and MUHZ to characterize respectively drought conditions, strong winds and heavy rainfalls, and the areas affected to multiple threats, considering the hazards at which power infrastructure are particularly vulnerable. At short term, under RCP4.5 and RCP8.5 hypotheses, the Southern Italy and Islands will already have to deal with a significant increase of drought conditions, that are projected to progressively extend from summer to autumn and then to spring, whereas the Central-Northern Italy will be mainly affected by storms. A decrease of wet days and, consequently, a lengthening of dry spells are generally expected, but extreme precipitations will be more frequent and more destructive, in particular over Po Valley and the eastern Italian coasts. Po Valley, Adriatic and Tyrrhenian coasts are projected to be the areas most exposed to a plurality of threats, but no Italian region will be safe from an enhancement of climate change hazards both in frequency and intensity during the 21 st century in all three RCPs, with more and more severe conditions from RCP2.6 to RCP8.5 and from short- to long-term.