Darwish, K.; Smith, S.E.; Torab, M.; Monsef, H., and Hussein, O., 2017. Geomorphological changes along the Nile Delta coastline between 1945 and 2015 detected using satellite remote sensing and GIS. This study describes geomorphologic changes along the Nile Delta coastline between 1945 and 2015. The study used topographic maps produced by the Egyptian Geological Survey in 1945 and Landsat satellite imagery taken between 1973 and 2015. The study found that the coastline's geomorphology greatly changed during this time period, especially at Damietta and Rosetta promontories, which were highly eroded after construction of the Aswan High Dam. Other stretches of the coastline also eroded, while some accretion occurred along the coastline down-drift from the promontories. The trend has been erosion of the beaches along the Nile promontories and accretion within the embayments between the promontories, resulting in an overall smoothing of the coastline. A portion of the eroded material has accreted in t...
17 April 2015 in Environmental Monitoring and Assessment
The objective of this study was to assess coastal dynamics of the Sinai Mediterranean coastline (SMC) between 1990 and 2020. In this study, remote sensing imagery and geographic information systems-based spatial computing methods were used for coastline change analysis. The study found that the SMC experienced major morphological changes during the period of study. The results show a spatial heterogeneity of coastline change rate over the study period with some periods of rapid change and other periods of stability. The overall analysis during the period of study indicated that the coastline has retreated landward approximately 555 m; the average annual erosion rate was 2.5 m/year. The percentage of the eroded section in the coastline is 60% with the remaining 40% either advancing or remaining stable. Sections of the coastline accreted as much as 542 m. The GIS-based DSAS model application used in this study is unique because it measured spatial variations of coastline dynamics over time using a multiple statistical approach.
The objective of this study was to provide an assessment of coastline extraction and change analysis using different sensors from three satellites over time. Imagery from Landsat-8 OLI, Sentinel-2A MSI, and PlanetScope-3B were used to detect geomorphological changes along the El-Alamein coastline on the Mediterranean Sea between August 2016 and August 2021. The normalized difference water index (NDWI) was applied to automate, detect and map water bodies based on thresholding techniques and coastline extraction. The extracted coastlines were analyzed using geographic information systems (GIS)-based digital shoreline analysis system (DSAS.v5) model, a GIS software tool for the estimation of shoreline change rates calculated through two statistical techniques: net shoreline movement (NSM) and end point rate (EPR). The results indicate that measuring coastline morphological change using satellite-based imagery depends very much on the resolution of the imagery. It is necessary to tailor the selection of imagery to the accuracy of the measurement needed. Higher resolution imagery such at PlanetScope (3 m) produces higher resolution measurements. However, medium resolution imagery from Landsat may be sufficiently good for objectives requiring less spatial resolution.