Greenhouse gas measurements acquired from the Plateau Rosa station, which is suitable for the measurement of the natural background of climate-altering gases, allowed the SSP2-4.5 and RCP4.5 scenarios, marked by partial reductions in greenhouse gas emissions, to be recognized as the most representative of those assumed in the development of climate simulations.

Wet snowfalls are one of the most impactful weather threats to electrical infrastructure, as they promote the formation of heavy sleeves that can damage overhead power lines, leading to insulation losses and/or structural failure. To study their evolution in frequency and intensity, 12 Euro-CORDEX climate models (spatial resolution ~12 km) in RCP4.5 and RCP8.5 (without mitigation) configurations were considered.

In addition, the MERIDA OI (4 km) meteorological reanalysis dataset was used to apply bias-correction to the temperature provided by the climate models and implement a new version of the “Makkonen model” aimed at studying sleeve formation on conductors at the climatological scale. Having validated the model for several observed cases, future projections were developed over the national territory for the periods 2021-2040, 2031-2050, 2041-2060, 2061-2080, and 2081-2100, with focus on some locations. Finally, several probability maps of sleeve loading at different intensity levels were calculated through Extreme Value Analysis.

The research shows that, due to global warming, wet-snow phenomena will tend to decrease on average during the 21st century, not excluding the occurrence of episodes of high intensity due to climate variability, instead they may intensify at higher altitudes in Alpine regions. These trends appear to be more pronounced in the RCP8.5 emission pathway than in the RCP4.5 pathway, and significant changes are expected from the second half of the century.

High winds pose another major threat to grid security. Using modeling data of average and maximum daily wind intensity, future scenarios were developed for the periods 2021-2050, 2041-2070, 2071-2100, characterizing average and extreme values of wind intensity. The projections indicate substantial stationarity of the anemological regime and, in particular, no significant change in the occurrences of extreme winds.