The Dead Sea

The Dead Sea is 8.6 times saltier than the ocean. Experts say that it is nine times saltier than the Mediterranean Sea. This salinity makes for a harsh environment where animals cannot flourish and boats cannot sail. 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.

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.

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, creating pools and quicksand pits along the edges.

In Arabic the Dead Sea is called al-Bahr al-Mayyit ("the Dead Sea"). Another historic name in Arabic was the "Sea of Zo'ar", after a nearby town.

Many people believe that the mud of the Dead Sea has special healing and cosmetic uses. The Dead Sea receives less than 100 millimetres (3.94 in) mean annual rainfall and has a summer average temperature between 32 and 39 °C (90-102 °F). Winter average temperatures range between 20 and 23 °C (68-74 °F).

One of the most unusual features of the Dead Sea is its discharge of asphalt. From deep seeps, the Dead Sea constantly spits up small pebbles of the black substance. After earthquakes, chunks as large as houses have been found.

The Dead Sea area has become a major centre for health research and treatment for several reasons. The mineral content of the waters, 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 suffering reduced respiratory function from diseases such as cystic fibrosis seem to benefit from the increased atmospheric pressure.

Sufferers of the skin disorder psoriasis also benefit from the ability to sunbathe 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. Furthermore, Dead Sea salt has been found to be beneficial to psoriasis patients.

The Dead Sea's 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. Researchers from Hebrew University found the Dead Sea to be teeming with a type of algae called Dunaliella. The Dunaliella in turn nourished carotenoid-containi ng (red-pigmented) halobacteria whose presence is responsible for the color change. Since 1980, the Dead Sea basin has been dry and the algae and the bacteria have not returned in measurable numbers.

Many animal species make their homes in the mountains surrounding the Dead Sea. A hiker can see camels, ibex, hares, hyraxes, jackals, foxes, and even leopards. Hundreds of bird species inhabit the zone as well. Both Jordan and Israel have established nature reserves around the Dead Sea.