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In the Aeolian Archipelago (southern Tyrrhenian Sea), Panarea Island and the islets of Bottaro, Lisca Bianca, Lisca Nera and Dattilo, is undergoing sea level rise, land subsidence, coastal erosion and beach retreat that are posing continuous threats to coastal stability and infrastructures built along the coastal zone. With the aim to assess the coastal changes by the end of 2100 according to the IPCC climatic scenarios, that predict a global sea level rise even more than 1 m, a detailed evaluation of the potential coastal flooding has been estimated in the frame of the PANDCOAST project, funded by the INGV.This work focuses on the use of Unmanned Aerial Vehicles (UAVs) imagery combined with multibeam bathymetry data collected in different years for the generation of the very high-resolution Digital Terrain and Marine Model (DTMM) of the Panarea Island and its archipelago. Scenarios are based on the determination of the current coastline position, high resolution Digital Terrain and Marine Models, vertical land movements and climatic projections. The data fusion of detailed topographic data, up to 2 cm/pixel for the subaerial sector with sea level rise projections released by the Intergovernmental Panel on Climate Change (IPCC) for the SSP2.6 and SSP5 climatic scenarios for this area, are used to map the expected multi-temporal sea level rise scenarios for 2050 and 2100.In the analysis have been incorporated the effects of the vertical land movements (VLM) as estimated by the Global Navigation Satellite System (GNSS) network located in the archipelago. Assuming constant rates of VLM for the next 80 years, relative sea level rise projections provide values between 31±11 cm by 2050 and 104±27 cm by 2100 for the IPCC AR6 SSP8.5 scenarios and at 27±10 cm by 2050 and 73±24 cm by 2100, for the IPCC AR6 SSP2.6 scenario, with small variations in the individual islets of the archipelago. With these scenarios, the lowest elevated coasts of the islands are exposed to increasing marine flooding, especially during storm surges and high water levels particularly heavy from the north-western sectors.

The Ionian Sea in southern Italy is at the center of active interaction and convergence between the Eurasian and African-Adriatic plates in the Mediterranean. This area is seismically active with instrumentally/historically-recorded Mw > 7.0 earthquakes and it is affected by recently-discovered long strike-slip faults across the active Calabrian accretionary wedge. Many mud volcanoes occur on top of the wedge. A recently-discovered one (here named Bortoluzzi Mud Volcano, BMV) was surveyed during the Seismofaults 2017 cruise (May 2017). Bathymetric-backscatter surveys, seismic reflection profiles, geochemical and earthquake data as well as a gravity core are here used to geologically, geochemically, and geophysically characterize this structure. The BMV is a circular feature ≃22 m high and ≃1100 m in diameter with steep slopes (up to a dip of 22°). It sits atop the Calabrian accretionary wedge and a system of flower-like oblique-slip faults that are probably seismically active as demonstrated by earthquake hypocentral and focal data. Geochemistry of water samples from the seawater column on top of the BMV shows a significant contamination of the bottom waters from saline (evaporite-type) CH4-dominated crustal-derived fluids similar to the fluids collected from a mud volcano located in the Calabria main land over the same accretionary wedge. These results attest for the occurrence of an open crustal conduit through the BMV down to at least the Messinian evaporites at about −3000 m. This evidence is also substantiated by Helium isotope ratios and by different geochemical data from three sea water columns located elsewhere in the Ionian Sea. Conclusions are drawn on the origin of the BMV and on the potential of this type of structures for tracking the seismic cycle of active faults. Due to the widespread diffusion of mud volcanoes in seismically active settings, this study may contribute to indicate a potential and feasible future path for the use of these ubiquitous structures in favor of the mitigation of natural hazards.