Within an E.U.-funded project, BESS (Pocket Beach Management and Remote Surveillance System), the notion of a geographic information system is an indispensable tool for managing the dynamics of georeferenced data and information for any form of territorial planning. This notion was further explored with the creation of a WebGIS portal that will allow local and regional stakeholders/authorities obtain an easy remote access tool to monitor the status of pocket beaches (PB) in the Maltese Archipelago and Sicily. In this paper, we provide a methodological approach for the implementation of a WebGIS necessary for very detailed dynamic mapping and visualization of geospatial coastal data; the description of the dataset necessary for the monitoring of coastal areas, especially the PBs; and a demonstration of a case study for the PBs of Sicily and Malta by using the methodology and the dataset used during the BESS project. Detailed steps involved in the creation of the WebGIS are presented. These include data preparation, data storage, and data publication and transformation into geo-services. With the help of different Open Geospatial Consortium protocols, the WebGIS displays different layers of information for 134 PBs including orthophotos, sedimentological/geomorphological beach characteristics, shoreline evolution, geometric and morphological parameters, shallow water bathymetry, and photographs of pocket beaches. The WebGIS allows not only for identifying, evaluating, and directing potential solutions to present and arising issues, but also enables public access and involvement. It reflects a platform for future local and regional coastal zone monitoring and management, by promoting public/private involvement in addressing coastal issues and providing local public administrations with an improved technology to monitor coastal changes and help better plan suitable interventions.

Pocket beaches (PBs) are among the most attractive tourist sites and economic development contributors in coastal areas; however, they are negatively impacted by the combined effects of climate change and anthropogenic activities. Generally, research on PBs is conducted from the beach towards offshore. Studies on the land use/land cover (LULC) of PBs are limited and currently lacking. Such studies deserve more investigation due to the importance of LULC in PBs’ functioning. In this study, supervised classification methods were investigated for LULC mapping of the PBs located in the province of Messina. Sentinel-2B satellite images were analyzed using maximum likelihood (MaL), minimum distance (MiD), mahalanobis distance (MaD) and spectral angle mapper (SAM) classification methods. The study was conducted mainly in order to determine which classification method would be adequate for small scale Sentinel-2 imagery analysis and provide accurate results for the LULC mapping of PBs. In addition, an occurrence-based filter algorithm in conjunction with OpenStreetMap data and Google Earth imagery was used to extract linear features within 500 m of the inland buffer zone of the PBs. The results demonstrate that information on the biophysical parameters, namely surface cover fractions, of the coastal area can be obtained by conducting LULC mapping on Sentinel-2 images.

The amount of Earth observation images available to the public has been the main source of information, helping governments and decision-makers tackling the current world’s most pressing global challenge. However, a number of highly skilled and qualified personnel are still needed to fill the gap and help turn these data into intelligence. In addition, the accuracy of this intelligence relies on the quality of these images in times of temporal, spatial, and spectral resolution. For the purpose of contributing to the global effort aiming at monitoring natural and anthropic processes affecting coastal areas, we proposed a framework for image processing to extract the shoreline and the shallow water depth on GeoEye-1 satellite image and orthomosaic image acquired by an unmanned aerial vehicle (UAV) on the coast of San Vito Lo Capo, with image preprocessing steps involving orthorectification, atmospheric correction, pan sharpening, and binary imaging for water and non-water pixels analysis. Binary imaging analysis step was followed by automatic instantaneous shoreline extraction on a digital image and satellite-derived bathymetry (SDB) mapping on GeoEye-1 water pixels. The extraction of instantaneous shoreline was conducted automatically in ENVI software using a raster to vector (R2V) algorithm, whereas the SDB was computed in ArcGIS software using a log-band ratio method applied on the satellite image and available field data for calibration and vertical referencing. The results obtained from these very high spatial resolution images demonstrated the ability of remote sensing techniques in providing information where techniques using traditional methods present some limitations, especially due to their inability to map hard-to-reach areas and very dynamic near shoreline waters. We noticed that for the period of 5 years, the shoreline of San Vito Lo Capo sand beach migrated about 15 m inland, indicating the high dynamism of this coastal area. The bathymetric information obtained on the GeoEye-1 satellite image provided water depth until 10 m deep with R2 = 0.753. In this paper, we presented cost-effective and practical methods for automatic shoreline extraction and bathymetric mapping of shallow water, which can be adopted for the management and the monitoring of coastal areas.

<p>Hundreds of thousands of people live and work in areas at risk of flooding, especially into deep valleys over the Italian territory. Floods cause fatalities and considerable economic damages to infrastructures and to private and public properties, besides impacting on fluvial-geomorphic landforms. During the last decade, these extreme events are occourring more frequently, contributing to increase the public awareness on the potential damaging consequences, and on the demand of monitoring and post-event assessment procedures. However, an efficient, systematic and accurate framework of post-event actions aiming to document the impacts of such disasters in terms of flooded areas, meteorological controls, geomorphological and vegetation change, is rare.</p><p>On this background, the role of the post-event surveys is fundamental to provide information/data and to increase knowledge for improving forecasting and designing the countermeasures. Flood events documentation consists in a series of field- and desk-based activities that request considerable consuming resources (time and human) and a high level of technical expertise. The post-event analyses, then, should correctly balance the different activities and efforts to reduce time and costs and then become a part routine post-event procedure.</p><p>The present study shows the results of a field campaign carried out after a flash flood occurred on June 12th 2019 along a 2 km stretch of Pioverna torrent in Valsassina (Lombardy, Italy). The survey consisted in collecting meteorological data, and video and pictures taken by inhabitants and rescuers for reconstructing field evidences of flood and the peak discharge. Few weeks after the flood, an Unmanned Aerial Vehicle (UAV) captured multiple images that were processed by Structure from Motion (SfM) photogrammetric algorithms, together with permanent Ground Control Points (GCPs) positioned on the riverbed and the streambanks, in order to obtain a high-resolution topography data. The methodology is likely to be truly effective if a pre-event photogrammetric survey is available for the same stretch, as in the present case.</p><p>The UAV photogrammetric surveys expected to be able to detect: (i) the geomorphological changes including streambank erosion, sediment deposition and the general stream evolution; (ii) the flood-damaged areas including buildings and roads (useful for estimating economic losses) and hydraulic structures (useful for giving a priority to the restoration works); (iii) the change in vegetation patterns that strongly influence the fluvial geomorphological processes.</p><p>In such a perspective, a simple methodology has been developed and applied to obtain a good balance between accuracy, time-consuming, efforts and collected data. In addition, it has been showed how the post-flood campaign has a strategic significance for a wide spectrum of multidisciplinary aspects (damage assessment, hydraulics, and ecology) and allows to rapidly reconstruct the flood event and its consequences. Standardizing such procedure should be extremely important to collect similar data, useful to improve specific guidelines and post-emergency management plans.</p>