Deepest depression exposed

According to the latest figures issued by Israeli Oceanographic institute (in 2010), the lowest dry land on Earth can be found 423 m below sea level on the shores of the Dead Sea – an extremely salty lake on the Israel–Jordan border. In recent years, large scale irrigation projects upriver from the lake have reduced the inflow rate to less than the rate of evaporation, causing the water levels to drop. As a result, the lowest exposed depression on Earth is around 20 metres lower than it was in the early 1990s. If this imbalance continues, the Dead Sea will continue to shrink until it reaches a new equilibrium with the reduced surface area of the lake bringing the evaporation rate down far enough that it no longer exceeds the inflow rate.

The Dead Sea is what is called an endorheic lake, meaning that it has no outflow to the sea. Endorheic lakes form when a river flows into a basin and gets trapped. As the basin fills with water, the surface area of the resulting lake increases and so, therefore, does its rate of evaporation. In most parts of the world, the rate of evaporation is never high enough to counteract the inflow rate, meaning that the basin will continue to fill until it overflows and the river is able to continue its journey downwards to the sea. In very hot and dry climates, however, the rate of evaporation and the inflow rate sometimes cancel each other out, creating lakes with a surface that is lower than sea level.