Quantification of Deltaic Coastal Zone Change Based on Multi-Temporal High Resolution Earth Observation Techniques (original) (raw)
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10th International Congress of the Hellenic Geographical Society, 2014
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The continuous change of shoreline boundaries due to natural or human causes has created the necessity for shoreline monitoring. Sedimentation occurs in shallow water level areas where a river or creek discharges into the sea or ocean. Continuous erosion and sediment accumulation cause shoreline changes, which may result in losing land soil or destructive accumulation of sediments. This catastrophic natural event may harm coastal lands with economic value, such as beaches, agricultural areas, residential buildings, and hotels. Traditional shoreline monitoring is done by physically collecting data over a period of time in the desired location. Standard methodology requires many things, such as workforce, funding, and, more importantly, a long duration. This study examines monitoring shoreline change in Alanya, Türkiye, with Digital Shoreline Analysis System (DSAS) by using geographical information systems and remote sensing analysis. The study area is narrowed step by step by constructing different models to compare the results. The smallest microzone is selected as Dim River mouth in Alanya, Türkiye, for being naturally dynamic and having less human activity, which may cause artificial changes in shorelines. The research consists of analyzing the satellite images from two different satellites, Landsat and Planet, and corresponding reanalysis data of the coastline. Based on the results, seasonal and cyclical behavior is obtained in the area. As the study area decreases, the changes in shoreline changes. Throughout the study area, mostly erosion is observed. In Dim River Mouth, the seasonal change in shorelines is obtained roughly between -25 and +25 meters for Landsat-8 imagery and -8 and +4 meters for Planet imagery.
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