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Coastal environments are under successive physical and morphodynamical pressure. Nowadays, it is crucial to have a reliable and simple tool in order to measure the changes occurred diachronically. Among the research community there have been developed and applied many relative statistical models which are quite reliable. In this study we try to compare in statistical terms the results of the most famous free extension, suited for commercial software for shoreline monitoring: The Digital Shoreline Analysis System (DSAS) and the Analyzing Moving Boundaries Using R (AMBUR). Both software are free open-source tools for shoreline analysis in Geographic Information System environment. The test site is located in the northwestern Peloponnese, Greece, between two littoral villages named Rogitika and Kaminia situated in the Gulf of Patras. The shoreline length is more than 6 kilometers. High-resolution images (air-photos mosaic and very high-resolution satellite data) for the years 1987, 1996, 2008, and 2018 were used. The images have been orthorectified and georeferenced to Hellenic Geodetic Reference System of 1987 (Greek Grid) using Leica Photogrammetry Suite (LPS). The data spatial resolution ranges from 0.25 m to 1.00 m. Transects every 50 meters were created and used for the measurements. We digitized the relative shorelines and we computed and compared the End Point Rate (EPR) rates calculated from both tools for three periods such as 1987-2018, 1996-2018, and 2008-2018 respectively. EPR calculates the annual rate of erosion or accretion computed in a specific transect. The rates between -0.10 and + 0.10 m were considered that correspond to a “stable” area. The tide height rates were considered negligible (0.00 m ± 10.00 cm) and so did not affect the computations. Moreover, a Linear Regression statistical process applied for correlation of EPR calculated rates from AMBUR and DSAS seaward and landward models. Finally, the results are presented and discussed in the current paper.
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