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Field data, U‐Th dating and amino acid racemisation (AAR) and epimerisation (IAE) analyses were performed in a sector of the Ionian coast of Apulia. Palaeoshoreline 1 (PS1) was identified at +40 ± 5 m with the associated terraced deposit 1 (TD1). Palaeoshoreline 2 (PS2) was identified at +30 ± 2 m with the associated terraced deposit 2 (TD2), characterised by five sub‐units. The sub‐units that mark the transgression have an age of 127.851 ± 1.47 ky BP (by U‐Th dating) and 128.4 ± 26.2 ky BP (by AAR); one of sub‐units marking the highstand falls within aminozone E (MIS 5.5) based on IAE. Palaeoshoreline 3 (PS3) was identified at +19 ± 2 m with the associated terraced deposit 3 (TD3); they mark the occurrence of a second, lower elevation MIS 5.5 highstand. TD3 dates back to aminozones E–D (MIS 5.5‐MIS 5.3) based on IAE and to 122.49 ± 1.25 ky BP by U‐Th dating. We considered two scenarios where the first highstand of MIS 5.5 occurred at 125 and 123 ky BP, with a sea level at +7.5 ± 1.5 m; we then calculated the uplift rate of PS2 for both scenarios: it resulted to be 0.18 ± 0.03 mm/year. These uplift rates were used to calculate the position of PS3 at 122.49 ± 1.25 (rounded to ⁓122 ky BP) as well as the position of the layer dated to 127.851 ± 1.47 ky BP (rounded to ⁓128 ky BP). The position of PS3 at the time of its formation (i.e., the sea level at ⁓122 ky BP, corresponding to the second highstand of MIS 5.5) was calculated to be −2.96 ± 5.42 m for Scenario 1 and −3.32 ± 5.47 m for Scenario 2. The sea level obtained by the layer dated to ~128 ky BP was found to have a value of −11.79 ± 6.29 m. Finally, we reconstructed a relative sea level (RSL) trend suggesting two main highstands during MIS 5.5, with the earlier higher than the second. [ABSTRACT FROM AUTHOR]

Mediterranean hurricanes, also known as medicanes, can cause significant damage to coastal communities. Consequently, they have been the subject of intense study in recent decades. Geographic Information Systems (GISs) and Web-GIS applications are essential for processing and analyzing geographic data from various sources, particularly in the field of spatial planning. Due to their ability to integrate heterogeneous information, these tools can provide experts with a comprehensive overview of relevant geospatial data. Here, we present ARCHIMEDE, a relational geodatabase connected to an open-source Web-GIS platform focused on Mediterranean hurricanes that contains data from recent research on these extreme weather phenomena. These datasets comprise climatic and oceanographic data obtained from remote sensing techniques as well as seismic and geomorphological data obtained from field observations. Consequently, this Web-GIS platform can enhance our understanding of Mediterranean cyclones by relating the physical properties of these natural phenomena with their impacts on coastal regions. ARCHIMEDE is an innovative tool for the dissemination of geographic information to stakeholders, researchers, and decision-makers, offering valuable support for the development of robust coastal management strategies aimed at mitigating the challenges posed by Mediterranean hurricanes. [ABSTRACT FROM AUTHOR]

A field assessment was carried out in May 2023 in a natural protected area in South Italy to investigate the real-time behavior and fate of common marine litter items at different depths at the nearshore and foreshore under low energetic conditions. The field data were also compared with theoretical values calculated using theoretical formulations considering the Stokes drift current, wind-induced current, and current at breaking position. The wind approached from N to W, with values ranging from 2.4 to 3.8 m/s. The propagated significant wave height ranged from 14 to 21 cm, with an associated period of 3 s. Items with a positive buoyancy recorded different velocities. Very protruding (above water surface) items were greatly affected by windage and recorded velocities from 0.23 to 0.33 m/s; higher than the theoretical values that do not take into account windage. Theoretical values correctly predicted the velocity of other less-protruding items but slightly underestimated the velocity of neutral buoyancy items, evidencing in both cases the low relevance of the Stokes drift current. Items with a negative buoyancy moved (or not) in the bottom with different velocities. Different behaviors were observed at the breaking point, where items surfed (or not) spilling breaking waves, and at the foreshore, where items moved along the plunge step or in a "zig–zag" movement due to a swash–backwash process. [ABSTRACT FROM AUTHOR]

Coastal erosion occurs due to different processes involving physical and ecological systems. One of these factors is the degree of water stress experienced by dune vegetation. While healthy dune vegetation can help to stabilize the dune systems, water-stressed vegetation can instead enhance dune erosion. In this study, remote sensing techniques were used to monitor the water stress affecting the dune vegetation in dune systems along the alluvial plain of the Chiatona coast (Apulia, Southern Italy) located on the Ionian Arc. Multispectral satellite data from Landsat 8/9 and Sentinel-2 were used to assess the water stress at different spatial scales over a 4-year monitoring period from 2019 to 2023. The normalized difference vegetation index (NDVI) and the normalized difference moisture index (NDMI) were used to identify dune surfaces that were experiencing water stress. Furthermore, a terrestrial laser scanner and LiDAR data were acquired at different temporal ranges in areas affected by water stress to highlight coastal changes in areas associated with unhealthy dune vegetation. A large drop in NDVI values was observed in May 2020 due to the occurrence of coastal fires in some parts of the Chiatona coast. Geoelectrical surveys were conducted to investigate if coastal fires were capable of saline groundwater contamination, potentially enhancing dune erosion in these areas. The joint analysis of remote sensing, topographical, and geoelectric data showed that water stress reduced the amount of healthy dune vegetation, triggering dune deflation processes that resulted in increased coastal erosion rates, while also leading to the saline contamination of groundwater. [ABSTRACT FROM AUTHOR]

In this research, an operative procedure for the evaluation of land use change that occurred in highly reclaimed coastal areas from the middle of the XIX century up to the present day is proposed. The multitemporal analysis envisages the use of historical maps, aerial photographs, and satellite images, whose interpretation is performed in a GIS environment. The proposed methodological approach starts from the interpretation of the symbols used in the legend of the historical maps. Subsequently, in order to compare historical information with the most recent land use classifications (i.e., CORINE land cover), a set of twenty-two macro-categories is proposed to find a compromise between a highly detailed land use classification and its applicability to both historical and present-day data. The study area is located in the coastal sector of the Tavoliere di Puglia (Apulia region, Southern Italy), the second-largest coastal plain in Italy. In this area, environmental changes were mostly driven by extensive reclamation and drainage works, which allowed more than 170 km2 of land to be removed from coastal marshes and wetlands. The results show a strong increase in the surface occupied by arable land, urban areas, and saltwork, which today occupy about 57%, 3%, and 23% of the total investigated area, respectively. In contrast, the total surface occupied by grassland, pasture, meadow, and shrubland decreased from 59.6% in 1869 to 4.6% in the present-day setting. It is worth noting that although fluvial sediments were trapped and used to fill the marshy areas, the coastline prograded up to the first half of the XX century, favouring the formation of wide coastal dune systems. Nevertheless, the natural coastal resilience of the investigated system has been reduced since the second half of the XX century, probably as a consequence of the construction of numerous dams in the Ofanto River catchment, which represents the main river in the investigated area. [ABSTRACT FROM AUTHOR]

Extreme atmospheric-marine events, known as medicanes (short for "Mediterranean hurricanes"), have affected the Mediterranean basin in recent years, resulting in extensive coastal flooding and storm surges, and have occasionally been responsible for several casualties. Considering that the development mechanism of these events is similar to tropical cyclones, it is plausible that these phenomena are strongly affected by sea surface temperatures (SSTs) during their development period (winter and autumn seasons). In this study, we compared satellite data and the numerical reanalysis of SSTs from 1969 to 2023 with in situ data from dataloggers installed at different depths off the coast of southeastern Sicily as well as from data available on Argo floats on the Mediterranean basin. A spectral analysis was performed using a continuous wavelet transform (CWT) for each SST time series to highlight the changes in SSTs prior to the occurrence of Mediterranean Hurricanes as well as the energy content of the various frequencies of the SST signal. The results revealed that decreases in SST occurred prior to the formation of each Mediterranean hurricane, and that this thermal drop phenomenon was not observed in intense extra-tropical systems. The spectral analyses revealed that high CWT coefficients representing high SST energy contents were observed before the occurrence of a Mediterranean hurricane. This information may provide a useful fingerprint for distinguishing Mediterranean hurricanes from common seasonal storms at the onset of these events., (© 2024. The Author(s).)