Increased land subsidence and sea-level rise are submerging Egypt’s Nile Delta coastal margin
Egypt’s Nile delta, only ~1 m above mean sea level at the Mediterranean coast, is subject to uneven rates of submergence. This is a response to several factors leading to increasing land lowering (subsidence) of the northern delta and adjacent seafloor, plus an accelerating rise in eustatic (world) sea level in the Mediterranean. An average eustatic sea-level rise of ~3 mm/yr represents only ~26% to 45% of total relative sea-level rise measured along this margin. Three factors leading to subsidence are neotectonic lowering, compaction of Holocene sequences, and diminished sediment replenishment by much reduced Nile flow to Egypt’s coast.