It is referred to as Al-Bahr Al-Mayyit in Arabic and Yam Ha-Melah in Hebrew. It is a landlocked saltwater lake in southwestern Asia, lying between Israel and Jordan. Its shore, which averages about 400 meters below sea level, is the lowest place on the Earth’s surface. It is the saltiest body of water in the world; about nine times as salty as the ocean. We are referring to the Dead Sea.
Physical features
The Dead Sea, whose Hebrew name means "Salt Sea", lies between the hills of Judaea to the west and the Transjordanion plateaux to the east; it lies in the Ghor, a deep fault or break in the Earth’s crust. The lake covers an area of about 1040 square kilometers. It is about 18 kilometers wide at its widest point and about 80 kilometers long.
The peninsula of Al-Lisan (the “tongue”) divides the lake on its eastern side into a large northern basin and a smaller southern basin. The northern basin encompasses about three-fourths of the lake’s total surface area. The deepest part of the lake lies in this area; the lake bottom lies about 400 meters below the surface and about 799 meters below mean sea level. The southern basin is shallower, with a depth of less than three meters on an average.
Climatic conditions
The Dead Sea lies in a desert where rainfall is scanty and irregular. The region receives less than 4 inches of rain annually. Winters too are mild, averaging 170 C in January at Sedom and 140 C at the northern end. Summers are hot, with the temperature ranging around 340 C in August at Sedom. There has been a recorded maximum of 510 C. Evaporation of the lake’s waters often creates a thick mist above the lake and is averaged at about 55 inches annually. Atmospheric humidity varies from 45 per cent in May to about 62 per cent in October.
Lake breeze is a common phenomenon, in which the breeze blows outward from the lake in all directions during the day. It then reverses direction to blow inward toward the centre of the lake at night, in the form of land breeze.
How it was formed
In the Jurassic and Cretaceous Periods, about 208 to 66.4 million years ago, the Mediterranean Sea covered extensive areas of Syria and Palestine. The upheaval of the seabed in the Miocene Epoch, about 23.7 to 5.3 million years ago, resulted in the formation of the upfolded Transjordanion highlands and the central range of Palestine, causing fault lines that formed the Dead Sea depression.
The Al-Lisan peninsula as well as Mount Sedom was formed as a result of movements in the earth’s crust. Strata of clay, marl, soft chalk and gypsum, interbedded with sand and gravel are features common to both, the peninsula and the western side of the Dead Sea Valley. It is thus possible to conclude that the uplifting of Mount Sedom and Al-Lisan formed a southern escarpment for the Dead Sea. The water broke through the western half to form the shallow southern end of the Dead Sea.
Its historical significance
The Dead Sea has been associated with biblical history since the time of Abraham and the destruction of the two cities of Sodom and Gomorrah, which once stood near the lake. It is believed that these cities, destroyed by fire from heaven because of their wickedness, are now possibly submerged in the southern part of the Dead Sea. It has been referred to in the Bible as the "Salt Sea".
Columns of salt rock on the shore may have the basis for the Biblical story of Lot’s wife who was turned into a pillar of salt as punishment for disobeying God. Ancient manuscripts known as the Dead Sea Scrolls were found in caves near the Dead Sea. Most of these scrolls date from about 100B.C. to about A.D.70.
The water in the Dead Sea
The salty waters of the Dead Sea appear smooth and sparkling. Rocky, barren lands surround the lake while steep, brightly colored cliffs rise above its eastern and western banks. With the exception of a few plants and brine shrimp, the lake is devoid of any other form of life and this is why the lake is also called the Dead Sea. The salty soil around the lake too makes it ill suited for the growth of plants. The extreme salinity prohibits the existence of any form of life except bacteria and a few halophytes (plants that grow in salty or alkaline salt).
Source
The River Jordan and several other smaller streams pour relatively fresh water into the lake, which then mixes with the salt water at the surface. Thermal sulphur springs are another source of water for the Dead Sea. The extreme heat in the area causes this water to evaporate rapidly. As a result, the Dead Sea never grows less salty.
Salinity
The salinity of the water can be attributed to the presence of large amounts of minerals occurring in the form of sodium chloride, bromine, calcium chloride, potassium chloride, hydrogen sulphide and various other sulphates and bicarbonates. The concentration of the salt gradually increases toward the bottom. At a depth of 130 feet, the salinity is less than 300 parts per 1000. It then passes through a transition zone where the water temperature is uniform and the salinity is approximately 332 parts per 1000. The deep waters are saturated with sodium chloride and are fossilized and therefore remain permanently at the bottom; the upper waters date from a few centuries after biblical times.
The Dead Sea constitutes an enormous salt reserve, which is exploited on a small scale by a number of companies.
The saline water of the Dead Sea has a high density. It provides great buoyancy, enabling swimmers to float with ease. Some people believe that bathing in the Dead Sea is healthful because of its high mineral content. Several health resorts in the area provide facilities for bathers.
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