The Dead Sea



The Dead Sea--"Sea of Salt", also Hebrew:     "The Sea of Death", also called the Salt Sea, is a salt lake bordering Jordan to the east and Israel and Palestine to the west. Its surface and shores are 423 metres (1,388 ft) below sea level, Earth's lowest elevation on land. The Dead Sea is 377 m (1,237 ft) deep, the deepest hypersaline lake in the world. With 33.7% salinity, it is also one of the world's saltiest bodies of water, though Lake Assal (Djibouti), Garabogazköl and some hypersaline lakes of the McMurdo Dry Valleys in Antarctica (such as Don Juan Pond) have reported higher salinities. It is 9.6 times as salty as the ocean. This salinity makes for a harsh environment in which animals cannot flourish, hence its name. The Dead Sea is 55 kilometres (34 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.

The Dead Sea has attracted visitors from around the Mediterranean basin for thousands of years. Biblically, it was a place of refuge for King David. It was one of the world's first health resorts (for Herod the Great), and it has been the supplier of a wide variety of products, from balms for Egyptian mummification to potash for fertilizers. People also use the salt and the minerals from the Dead Sea to create cosmetics and herbal sachets. In 2009, 1.2 million foreign tourists visited on the Israeli side. .....

The Dead Sea seawater has a density of 1.240 kg/L, which makes swimming similar to floating.



In Hebrew, the Dead Sea is....meaning "sea of salt" (Genesis 14:3). In prose sometimes the term Yām ha-Māvet ("sea of death") is used, due to the scarcity of aquatic life there. In Arabic the Dead Sea is called About this sound al-Bahr al-Mayyit.... ("the Dead Sea"), or less commonly   .... ("the Sea of Lot"). Another historic name in Arabic was the "Sea of Zoar", after a nearby town in biblical times. The Greeks called it Lake Asphaltites (Attic Greek ἡ Θάλαττα ἀσφαλτῖτης, hē Thálatta asphaltĩtēs, "the Asphaltite[9] sea"). The Bible also refers to it as Yām ha-Mizraî 

("the Eastern sea") and Yām ha-‘Ărāvâ (..."Sea of the Arabah").


The Jordan River is the only major water source flowing into the Dead Sea, although there are small perennial springs under and around the Dead Sea, forming pools and quicksand pits along the edges.  There are no outlet streams.

Rainfall is scarcely 100 mm (4 in) per year in the northern part of the Dead Sea and barely 50 mm (2 in) in the southern part. The Dead Sea zone's aridity is due to the rainshadow effect of the Judean Hills. The highlands east of the Dead Sea receive more rainfall than the Dead Sea itself.

To the west of the Dead Sea, the Judean Hills rise less steeply and are much lower than the mountains to the east. Along the southwestern side of the lake is a 210 m (700 ft) tall halite formation called "Mount Sodom".




Climate


The Dead Sea's climate offers year-round sunny skies and dry air. It has less than 50 millimetres (2 in) mean annual rainfall and a summer average temperature between 32 and 39 °C (90 and 102 °F). Winter average temperatures range between 20 and 23 °C (68 and 73 °F). The region has weakened ultraviolet radiation, particularly the UVB (erythrogenic rays), and an atmosphere characterized by a high oxygen content due to the high barometric pressure. The sea affects temperatures nearby because of the moderating effect a large body of water has on climate. During the winter, sea temperatures tend to be higher than land temperatures, and vice versa during the summer months. This is the result of the water's mass and specific heat capacity. On average, there are 192 days above 30C (86F) annually.



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.  These results show that the composition of the salt, as anhydrous chlorides on a weight percentage basis, 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.

An unusual feature of the Dead Sea is its discharge of asphalt. From deep seeps, the Dead Sea constantly spits up small pebbles and blocks of the black substance.  Asphalt coated figurines and bitumen coated Neolithic skulls from archaeological sites have been found. Egyptian mummification processes used asphalt imported from the Dead Sea region.


For Your Health


The Dead Sea area has become a major center for health research and treatment for several reasons. The mineral content of the water, the very low content of pollens and other allergens in the atmosphere, the reduced ultraviolet component of solar radiation, and the higher atmospheric pressure at this great depth each have specific health effects. For example, persons experiencing reduced respiratory function from diseases such as cystic fibrosis seem to benefit from the increased atmospheric pressure. 

The region's climate and low elevation have made it a popular center for several types of therapies:

Climatotherapy: Treatment which exploits local climatic features such as temperature, humidity, sunshine, barometric pressure and special atmospheric constituents

Heliotherapy: Treatment that exploits the biological effects of the sun's radiation

Thalassotherapy: Treatment that exploits bathing in Dead Sea water

Treatment for psoriasis 

Climatotherapy at the Dead Sea is an effective therapy for patients with psoriasis, who benefit from sunbathing for long periods in the area due to its position below sea level and subsequent result that many of the sun's harmful UV rays are reduced. 

Treatment for rhinosinusitis 

Rhinosinusitis patients receiving Dead Sea saline nasal irrigation exhibited significantly better symptom relief compared to standard hypertonic saline spray. 

Treatment for osteoarthritis 

Dead Sea mud pack therapy has been suggested to temporarily relieve pain in patients with osteoarthritis of the knees. According to researchers of the Ben Gurion University of the Negev, treatment with mineral-rich mud compresses can be used to augment conventional medical therapy.





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