Sullo spostamento di massi costieri causato da onde "estreme" (costa ionica salentina).

In autumn 2018, in Torre Suda (Ionian coast of the Salento peninsula) some coastal boulders were removed and transported by "extreme" waves; they were the subjects of a study, including in situ surveys, computerized elaborations, and specific hydrodynamic analysis. For one of these boulders, the associated detachment niche was identified. In this short note, a method is presented to relate the speed of the bore waves at the initial position of the boulder on the coastal platform with the dynamic conditions for which a boulder can be dislodged. In addition, the first results of the investigations are reported and possible amendments of the method are mentioned. The value of the wave height in the open sea was then determined; it resulted comparable with the height of the significant waves reported by the Liby station in Santa Maria di Leuca during the considered period. A further study started in the northern coastal stretch of Torre Sant'Isidoro. Here, five associations between coastal boulders and initial positions were defined. In this case, the use of the proposed method returned values of wave heights in open sea comparable with the calculated heights of the significant waves, based on the data for return periods of 50- 100 years provided by the national wave network concerning the Crotone buoy. Finally, it is emphasized that, due to the expected increase in storm intensity, it is necessary to deepen the knowledge on coastal dynamics, despite the considerable uncertainties for the calculation of the parameters of the causative waves, since the concurrent factors are numerous and difficult to measure.