Since the early 1950s, Greece has been a popular travel destination providing high-quality tourism services. This was amplified by its diverse landscape, extended sandy beaches, scattered archaeological sites, people’s mentality, and adequate infrastructure. In particular, the south Aegean Archipelago attracts more than six million (6,000,000) visitors annually, approximately 27% of tourist arrivals in Greece. The carrying capacity assessment of the South Aegean region aims to improve the already high standards of the offered tourist services. Seventeen appropriate variables were analyzed to assess and increase tourism attractiveness by alternative products for long-term and sustainable management. Furthermore, the outcomes of the carrying capacity indicators application provide specialized solutions to control the over-tourism impact, mitigate the natural environmental degradation, and establish a roadmap for sustainable development in the study area. The required data were interpreted based on the PAP/RAC 1997 and WTO, enriched with more suitable variables from national and international literature to determine the carrying capacity. Therefore, the selection of seventeen (17) most representative indicators was unavoidable. Finally, the calculation of the different indexes showed that Mykonos and Thira are far above the indicator scale limits and are facing over-tourism issues. Additionally, the numbers of tourists concentrated in the abovementioned islands may accelerate the environmental degradation and, as a result, the tourist product will be downgraded. The set of these seventeen indicators works best since low, obfuscated, or no environmental data are available for the South Aegean region from the official state agency. Alternative tourist development and the extension of the tourist season based on local climatic conditions must be applied to ease the over-concentration and, consequently, the degradation of the tourist product. The large islands do not seem to face significant problems. However, the calculation of CCA will contribute to the decongestion of tourism concentration together with environmental decompression, leading to sustainable development in the South Aegean region.

The main objective of the present paper is to achieve the simulation of the long-term (e.g., annual) morphological evolution (bathymetry and shoreline) of a coastal area (Mastichari beach, Greece) due to wind-generated waves in an accurate and cost-effective way. For this purpose, wave climate schematization techniques are adopted in order to reduce the computational effort without losing or distorting the crucial information. Referring to the current practice, the wave chronology is not considered in detail in these acceleration techniques, and therefore, sea bottom and shoreline evolution are not estimated as a function of time. To fill this gap, a novel and easy-to-use chronology-based wave input reduction method is developed to produce representative wave time series of different intensities and durations. The performance of all the applied techniques in the present study is evaluated, and a comparative analysis is conducted. It is shown that the new chronology-based wave input reduction method can achieve a model run-time reduction of about 70%, while at the same time, it provides satisfactorily accurate results. In general, this research could be useful for coastal engineering studies and coastal zone monitoring, and thus, it would be a valuable tool for coastal engineers and marine scientists.

The variability of coastal storms over the years and direction is considered in a unified, innovative approach, providing crucial information for a wide variety of coastal engineering studies and wave energy applications under the impact of climatic change. Specifically, an alternative easy-to-apply technique is presented and applied to consider the storms’ direction as a covariate. This technique enables the probabilistic representation of coastal storms in every direction over the directional domain and is efficiently incorporated into a non-stationary directional extreme value analysis. The developed methodology is applied to six locations in the Greek Seas. Based on the derived results, the most likely and most extreme significant wave height estimates present, in general, a bimodal behavior with pronounced maxima. In particular, the first peak is observed before the twenty-first century, while the second peak is likely to occur around the middle of the twenty-first century. Furthermore, coastal storms coming from directions of large fetches are the most severe storms, presenting though a drop in their intensity at the end of the twenty-first century. On the contrary, coastal storms of fetch-limited directions may present minor variations in their probability distributions over the years.