4.4.3. Variations in the CVA Parameters

The variations in the E, IRU, and IR indexes from 2019 to 2021 (Tables 7–9, for IRU and IR values, average extreme wave conditions were considered) led to significant variations in the related CVA levels, which were calculated according to Formula 1 (see Section 3.3).

In the case of test area A (Figure 11), with regard to data for 2019 and 2021, some profiles show the shift from low to medium CVA levels (P1, P3) or vice versa (P4); however, the other profiles show an overall slight increase of CVA values while remaining within the

medium level. These data give evidence of an overall slight increase of erosion susceptibility along the Petacciato beach. Furthermore, CVA values obtained for profiles P5, P6, and P7 for 2020 are even higher than those of 2021, indicating a temporary major worsening of CVA conditions for the southern portion of study area A from 2019 to 2020, which then partially recovered in 2021.

**Figure 11.** Comparison of IRU, IR, and E indexes and related CVA levels obtained respectively for 2019, 2020, and 2021 for the beach profiles surveyed in test areas A and B (Petacciato and Campomarino beaches).

Test area B, however, started 2019 with CVA values at the medium up to the very high CVA level, decidedly higher with respect to those of test area A. A comparison of 2019 and 2021 highlights very modest changes in the CVA values for C1, C2, and C4, the shift of C3 from a medium to a high CVA level, and that of C5 from a very high to a high CVA level. The CVA levels of 2020 are lower with respect to those of 2021, with the only exception of C5, where no change occurs from 2020 to 2021. Overall, only profile C3 shows a significant change in CVA values from 2019 to 2021, which can be mainly attributed to the negative variations, first in IR and then in IRU values (see also Tables 8 and 9). This profile has undergone, among all, the most significant negative changes in CVA values and the consequent increase of coastal vulnerability, which must be related, in our opinion, to the impact of human interventions in the central portion of test area B, which have been already reported and discussed before.
