Thus, loss of forest cover accentuated cooling and drying of climates, leading to further contraction of forests. By early Oligocene time South America and Australia had moved far enough away from Antarctica to allow water from the southern oceans to become trapped in a current around Antarctica, where they became very cold. As a result, glaciers grew on Antarctica. Mid-Oligocene eustatic fall in sea level result of expansion of Antarctic glaciers. Expansion of glaciers and lowering of sea level.
Water evaporates less readily from cool seas.
Only 400 km 3 is replenished by rainfall and river input. At this rate the Mediterranean would dry up in 1000 years. Inflow of water from the Atlantic Ocean through the Strait of Gibraltar balances the Mediterranean's water deficit. Deep sea drilling found evaporite deposits in Mediterranean seafloor sediments. Deep valleys filled with Pliocene sediments were discovered lying beneath rivers that empty into the Mediterranean.