PSI - Issue 55

Francesca Frasca et al. / Procedia Structural Integrity 55 (2024) 32–38 Frasca et al., / Structural Integrity Procedia 00 (2019) 000 – 000

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3. Results Fig. 1 shows that the HDD in Trondheim will tend to decrease from RP to FF periods both in minimum and maximum values. HDD max will pass from 20°C (RP) to 15°C (FF) at the end of January, whereas HDD min will pass from 4°C (RP) to 1°C (FF) at the end of July. In addition, the number of the frost days will decrease from 177 to 81, meaning a significant reduction in the duration of the winter season. The number of both summer days and tropical nights is always zero in all periods and scenarios.

Fig. 1. Evolution of Heating Degree Days (HDD) in Trondheim from recent past (RP) to near and far future (NF and FF) in scenario SSP5-8.5 and the period corresponding to frost days (dark blue areas).

On the opposite, Fig. 2 shows that the CDD in Rome will tend to increase from RP to FF periods both in intensity (from 7°C to 14°C) and duration (from 5 to 7 months). Specifically, the number of the summer days will increase from 103 to 152 together with the number of the tropical nights (51 to 119). The occurrence of frost days has not been revealed.

Fig. 2. Evolution of Cooling Degree Days (CDD) in Rome from recent past (RP) to near and far future (NF and FF) in scenario SSP5-8.5 and the period corresponding to summer days (dark red areas).

In Fig. 3, it is evident that the total ED in RP period is predominated by heating in both cities (red histograms). On average, the cooling ED in Rome is 30% out of the total ED (blue histograms; T thresh = 20°C for CDD). It is worth noticing that if we propose a more sustainable setpoint to T thresh = 22°C for CDD calculation as proposed by Spinoni et al. (2018) in other applications, the cooling ED would be a little more than 20% out of the total ED.