An anonymous reader writes "A new model suggests that the Mediterranean Sea was filled in a gigantic flood some 5.3 million years ago. According to Daniel Garcia-Castellanos' paper in Nature, the sill at the Straight of Gibraltar gave way rather suddenly, with 40 cm of rock eroding and the water level rising by 10 m per day at its peak. They imagine a shallow, fast-moving stream of water (around 100 km/hr) several kilometers wide pouring into the basin with a flow greater than a thousand Amazon rivers — that's about 100,000,000 cubic meters per second."
The flood would have dropped worldwide sea levels by 9.5 meters, probably triggering climate changes. In this model the Mediterranean filled in anywhere from a few months to two years at the outside.