EROSION AND ACCRETION PATTERNS ALONG THE COASTAL ZONE OF NORTHERN SINAI, EGYPT *MAHMOUD H. AHMED, AHMED SWEDAN, TAHANI. H. EL-FATAH and ABDELAAL HASSAN *National Authority for Remote Sensing and Space Sciences, NARSS, mahahmed_narss@ yahoo.com Egyptian Geological Survey and Mining Authority, EGSMA easurements of long-term shoreline changes obtained from satellite images (1984 and 1996) and admiralty charts (1934) were used to determine rates of erosion and accretion as well as sediment transport system along the Sinai coast. The analyses, supplemented by available data on coastal processes, revealed major zones of beach accretion positioned to the east of the eroding Port Said and Bardawil headlands. Maximum erosion of 36 m/ yr was documented at the sand barrier of Bardawil lagoon headland, whereas accretion of 30 m/ yr was recorded east of Port Said. The regional scale erosion/ accretion pattern along Sinai coast was generally induced from the temporal variability in the direction and intensity of the incoming waves, longshore currents and the orientation of coastline. Due to the coast orientation, the long-shore sand transport resulting from the prevailing NW waves is almost unidirectional eastwardly all year long. The determined patterns of erosion and accretion have been used to identify two major sub-cells in the littoral zone, designated Port Said and Bardawil sub-cells.