If the dam's levees were closed, the water in the mediteranian would evaporate like it always does, but no new water would flow in from the Atlantic. This has

If the dam's levees were closed, the water in the mediteranian would evaporate like it always does, but no new water would flow in from the Atlantic. This has happened before. From 5.9 to 5.33 million years ago, the strait was closed and the entire sea evaporated. It will happen again, when the northward moving African plate collides with Europe.