Dead Sea – October 29th, 2008
Several different bodies of water are visible in this image of Israel/Palestine, Jordan and part of Syria: the Sea of Galilee to the North, the Dead Sea to the South, the Jordan River, and the Mediterranean Sea to the West.
The Dead Sea is a salt lake between Israel and the West Bank to the west, and Jordan to the east. It is connected to the Sea of Galilee by the Jordan River, The Dead Sea is 67 kilometres (42 mi) long and 18 kilometres (11 mi) wide at its widest point.
It lies in the Jordan Rift Valley, and its main tributary is the Jordan River. It is 420 metres (1,378 ft) below sea level, and its shores are the lowest point on the surface of the Earth on dry land. The Dead Sea is 330 m (1,083 ft) deep; the deepest hypersaline lake in the world.
The Dead Sea is also the world’s second saltiest body of water, after Lake Asal in Djibouti, with 30 percent salinity. It is 8.6 times saltier than the ocean, and nine times saltier than the Mediterranean Sea.
This salinity makes for a harsh environment where animals cannot flourish. The sea is called “dead” because its high salinity prevents macroscopic aquatic organisms, such as fishes and aquatic plants, from living in it, though minuscule quantities of bacteria and microbial fungi are present.
In the image we can observe the recession the Dead Sea has experienced over the last few decades; it has been rapidly shrinking because of diversion of incoming water. From an elevation of 395 m (1,296 ft) below sea level in 1970 it fell 22 m (72 ft) to 418 m (1,371 ft) below sea level in 2006, reaching a drop rate of 1 m (3 ft) per year.
The sea used to be one large body of water, but it is now separated into northern and southern sections. The southern end is fed by a canal maintained by the Dead Sea Works, a company that converts the sea’s raw materials. This company and another, Arab Potash (APC) use extensive salt evaporation pans that have essentially diked the entire southern end of the Dead Sea for the purpose of producing carnallite, potassium magnesium chloride, which is then processed further to produce potassium chloride.
These huge dikes are visible in the satellite image as lines in the southern part of the sea. Unfortunately, the activities of both of these companies contribute to the recession of the water.
The Dead Sea level drop has been followed by a groundwater level drop, causing brines that used to occupy underground layers near the shoreline to be flushed out by freshwater. This is believed to be the cause of the recent appearance of large sinkholes along the western shore – incoming freshwater dissolves salt layers, rapidly creating subsurface cavities that subsequently collapse to form these dangerous sinkholes.
One of the plans which were suggested as a means to stop the recession of the Dead Sea is to channel water from the Mediterranean or the Red Sea, either through tunnels or canals (the Dead Sea Canal).
The other important body of water visible in the upper part of main image is the Sea of Galilee, also Sea of Genneseret, Lake Kinneret or Lake Tiberias, is Israel’s largest freshwater lake, being approximately 53 km (33 mi) in circumference, about 21 km (13 mi) long, and 13 km (8 mi) wide. The lake has a total area of 166 km², and a maximum depth of approximately 43 m. At 209 meters below sea level, it is the lowest freshwater lake on Earth and the second-lowest lake in the world after the Dead Sea.
The Sea of Galilee is situated deep in the Jordan Great Rift Valley, the valley caused by the separation of the African and Arabian Plates and is fed partly by underground springs although its main source is the Jordan River which flows through it from north to south. Consequently the area is subject to earthquakes and, in the past, volcanic activity. This is evidenced by the abundant basalt and other igneous rocks that define the geology of the Galilee region.