Dead Sea

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??? ??????????????, Yam Ha-Mela? ??????? ????????, al-Ba?r l-Mayyit The Dead Sea

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The Dead Sea (Hebrew: ??? ??????????????, Yam Ha-Mela?, "Sea of Salt"; Arabic: ??????? ????????, al-Ba?r l-Mayyit, "Dead Sea") is a salt lake between Israel and the West Bank to the west, and Jordan to the east. It is 422 metres (1,385 ft) below sea level,[2] and its shores are the lowest point on the surface of the Earth on dry land. The Dead Sea is 378 m (1,240 ft) deep, the deepest hypersaline lake in the world. It is also one of the world's saltiest bodies of water, with 33.7 percent salinity. Only Lake Assal (Djibouti), Garabogazköl and some hypersaline lakes of the McMurdo Dry Valleys in Antarctica (such as Don Juan Pond and perhaps Lake Vanda) have a higher salinity. It is 8.6 times saltier than the ocean.[3] This salinity makes for a harsh environment where animals cannot flourish, hence its name. 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.

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A view from Israel looking across to Jordan

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Salt build-up along the shore

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Around three million years ago what is now the valley of the Jordan River, Dead Sea, and Wadi Arabah was repeatedly inundated by waters from the Mediterranean Sea. The waters formed in a narrow, crooked bay which was connected to the sea through what is now the Jezreel Valley. The floods of the valley came and went depending on long scale climatic change. The lake that occupied the Dead Sea Rift, named "Lake Sodom", deposited beds of salt, eventually coming to be 3 km (2 miles) thick. According to geological theory, approximately two million years ago the land between the Rift Valley and the Mediterranean Sea rose to such an extent that the ocean could no longer flood the area. Thus, the long bay became a lake. The first such prehistoric lake is named "Lake Gomorrah." Lake Gomorrah was a freshwater or brackish lake that extended at least 80 km (50 mi) south of the current southern end of the Dead Sea and 100 km (60 mi) north, well above the present Hula Depression. As the climate turned more arid, Lake Gomorrah shrank and became saltier. The large, saltwater predecessor of the Dead Sea is called "Lake Lisan."

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Pebbles cemented with halite

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The mineral content of the Dead Sea is very different from that of ocean water. The exact composition of the Dead Sea water varies mainly with season, depth and temperature. In the early 1980s the concentration of ionic species (in g/kg) of Dead Sea surface water was Cl- (181.4), Br- (4.2), SO42- (0.4), HCO3- (0.2), Ca2+ (14.1), Na+ (32.5), K+ (6.2) and Mg2+ (35.2). The total salinity was 276 g/kg.[9] These results show that w/w% composition of the salt, as anhydrous chlorides, was calcium chloride (CaCl2) 14.4%, potassium chloride (KCl) 4.4%, magnesium chloride (MgCl2) 50.8% and sodium chloride (common salt, NaCl) 30.4%. In comparison, the salt in the water of most oceans and seas is approximately 97% sodium chloride. The concentration of sulfate ions (SO42-) is very low, and the concentration of bromide ions (Br-) is the highest of all waters on Earth. The salt concentration of the Dead Sea fluctuates around 31.5%. This is unusually high and results in a nominal density of 1.24 kg/L. Anyone can easily float in the Dead Sea because of natural buoyancy. In this respect the Dead Sea is similar to the Great Salt Lake in Utah in the United States.

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Buoyancy caused by high salinity

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Salt evaporation pans

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In Judaism The human history of the Dead Sea goes all the way back to remote antiquity. Just north of the Dead Sea is Jericho. Somewhere, perhaps on the Dead Sea's southeast shore, would be the cities mentioned in the Book of Genesis which were said to have been destroyed in the time of Abraham: Sodom and Gomorra (Genesis 18) and the three other "Cities of the Plain" - Admah, Zeboim and Zoar (Deuteronomy 29:23). Zoar, however, escaped destruction when Abraham's nephew Lot escaped there from Sodom (Genesis 19:21-22). King David was said to have hidden from Saul at Ein Gedi nearby

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In Islam In Islamic tradition, the Dead Sea was about the land in which the Prophet Lut (Lot in the Hebrew scriptures) lived. The people of the towns and cities were wicked for their acts of raping men, robbery and murder, and had therefore been given a punishment for such deeds. The punishment arrived when angels in the form of beautiful men were sent down by God as guests for Lut to host. When Lut's people heard of the men, they rushed to Lut's house to misbehave and rape the men. This was their final test which they failed so the angel Gabriel raised the land where the prophet's people lived, tipped it upside down and threw it back on earth, causing the ground near the impact to cave in. Thus, the lowest land on Earth was formed because of this punishment. The non-believers (in the monotheism doctrine) were destroyed and the followers were saved. According to some interpretations, the sura of ar-Rum of the Quran refers to the Dead Sea as the lowest place on Earth.[13][14] aStakhfouroulah hil alli el athem Bedouin tribes have continuously lived in this area, and more recently explorers and scientists arrived to analyze the minerals and conduct research into the unique climate. Tourism in the region has been developed since the 1960s.

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Dead Sea at dusk (from Suwayma, Jordan)

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In recent decades, the Dead Sea has been rapidly shrinking because of diversion of incoming water. The southern end is fed by a canal maintained by the Dead Sea Works, a company that converts the sea's raw materials. From a depression of 395 m (1,296 ft) below sea level in 1970 [16] 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. Although the Dead Sea may never entirely disappear,[citation needed] because evaporation slows down as surface area decreases and salinity increases, it is feared that the Dead Sea may substantially change its characteristics[citation needed] . 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 sinkholes.[17]