Past sea level has varied by somewhat more than a hundred metres. This is primarily due to the growth and decay of ice sheets (mostly in the northern hemisphere) with water evaporated from the sea. The Mediterranean Basin's gradual growth as the Neotethys basin, begun in the Jurassic, did not suddenly affect ocean levels. While the Mediterranean was forming during the past 100 million years, the average ocean level was generally 200 metres above current levels. However, the largest known example of marine flooding was when the Atlantic breached the Strait of Gibraltar at the end of the Messinian Salinity Crisis about 5.2
Red Sea–Dead Sea Water Conveyance Valley in Jordan. The water would then flow down gravitationally through multiple pipelines to the area of the Dead Sea, followed by a drop through a penstock to the level of the Dead Sea near its shore, and then an open canal to the Sea itself, which lies about 420 meters below sea level. The project would utilize about 225 km of pipelines for seawater and brine, parallel to the Arabah Valley in Jordan. The project would also have about 178 km of freshwater pipelines to the Amman area. It also would include several water desalination plants and at least