Harnessing EO data for short-term surveillance and projections of the Nile Delta coastline and sea-level dynamics

The northern coastal zone of Egypt is a complex, resource-rich ecosystem, home to nearly 45% of the country's population and featuring diverse infrastructures, including urban centers, industrial estates, harbors, and agricultural lands. However, this region is highly vulnerable to climate change, particularly coastal erosion and Sea Level Rise (SLR). This study utilizes earth observation techniques to assess these risks, employing data from Landsat 8, Sentinel-2, Digital Elevation Model (DEM), and sea level datasets. The analysis of various SLR scenarios (1m, 2m, and 3m) indicates significant flooding risks. A 1-m rise could inundate approximately 5,097 km 2 , affecting nearly 10 million people, while a 3-m rise may submerge 11,444 km 2 , displacing around 16 million residents. Additionally, coastal erosion analysis from 2010 to 2020 revealed considerable land loss, with approximately 4.662 km 2 eroded over the decade at an average rate of -0.46 km 2 per year. For the short-term analysis (2010-2015), about -2.181 Km 2 of coastal areas were eroded, with an erosion rate of -0.44 km 2 /year. El-Behira, Alexandria, Kafr El-Sheik, and Port Said are the most vulnerable locations. These environmental threats pose severe socio-economic risks, potentially costing billions of dollars due to damage to infrastructure, agriculture, and local industries. This study underscores the urgent need for adaptive coastal management strategies to mitigate long-term risks and enhance the resilience of the Nile Delta region. • Assessed coastal vulnerability of Egypt’s northern Delta using Earth observation data • Modeled impacts of 1–3 m sea level rise scenarios on population and land inundation • Identified people at risk under the different SLR scenarios • Analyzed decadal coastal erosion trends using Landsat and Sentinel-2 imagery • Highlighted critical risk zones with economic losses