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What is under the Dead Sea?

Dead Sea

THE DEAD SEA IS a 390-square-mi (1,010-squarekm) salt lake located on the borders of PALESTINE, ISRAEL, and JORDAN. It is the lowest water point in the world, and its coast, at 1,292 ft below sea level (-395 m), is the lowest dry point on Earth. The lake is divided into two unequal parts by el-Lisan or “the Tongue,” which is a wide peninsula jutting from the lake’s southeastern shore. The northern part is larger and deeper, reaching 1,300 ft (400 m) in depth. In contrast, the southern side reaches only 35 ft (11 m) and averages only 13 ft (4 m) in depth.

The Dead Sea formed when two plates of the Earth’s crust began spreading apart, creating a low region, the Rift Valley system, where the crust is stretched quite thin. The Dead Sea is located in the region where the Earth’s surface has sunk, and the lake’s bottom is still sinking, as much as 13 in (33 cm) annually, an incredibly fast rate. In contrast, on the eastern and western sides of the lake, looming mountains range from 2,500 to 4,000 ft (762 to 1219 m) in height. The Jordan River is on the lake’s north, and hills of solid salt (Jebel Usdum or Mount Sodom) rise up on its southern border. Lower than surrounding topography, the Dead Sea is fed over 6.5 million tons of fresh water by the Jordan River and smaller streams every single day. (It should be noted that large-scale Israeli and Jordanian irrigation projects along the Jordan River have been causing the depth of the Dead Sea to decrease over the past 50 years; pollution is a concern.)

Because the lake has no outlets and is completely LANDLOCKED, the only way that water leaves is through evaporation; because the Dead Sea is located in a hot area with low precipitation, water evaporates to the degree that the sea level seldom fluctuates, other than because of irrigation, and what is left behind is the salt. Twenty-seven percent of the Dead Sea consists of solid substances, including sodium chloride, magnesium chloride, calcium chloride, potassium chloride and magnesium bromide. Potash, bromine, gypsum, salt and other products are commercially extracted from these waters, which become saltier as depth increases. At about 130 ft (40 m), there are approximately 300 grams of salt per kilogram of water, which is about 10 times the saltiness of typical ocean water.

Once the depth is greater than 300 ft (91 m), there are 332 grams of salt per kilogram, which is a state of saturation and explains the piles of salt found at the lake’s bottom. Due to this extreme saltiness, the Dead Sea supports no plant, animal, or fish life. If a fish swims from a stream into this lake, it is instantly killed and then preserved by the lake’s mineral salts. The only types of life, then, existing in the Dead Sea are microbes and highly specialized algae; on occasion, a seabird is seen resting on the lake’s surface.

Humans can swim in Dead Sea waters, but because of the extraordinarily high salt concentration and density of the water, the experience is more like floating. When a person exits the lake, the body is coated with white salts, just as the shores of the Dead Sea are covered with this substance, and the person’s skin can become irritated. The salts can irritate the eyes, and the water, if swallowed, tastes revolting because of the chloride of magnesium. Chloride of calcium gives the water its oily appearance.

The name Dead Sea is used in the Old Testament, although other biblical names are also listed for this body of water, including the Salt Sea, East Sea, Sea of the Plain, and Sodomitish Sea; the ancient cities of Sodom and Gomorrah were located at the lake’s southwestern coast. Yet another name is the Lake of Asphalt, given because of the quantities of bitumen that rise to the surface of this lake, and current inhabitants call this body of water the Sea of Lot.

This region is famous for the Dead Sea Scrolls found in 11 caves in nearby Qumran from 1947 to 1956. Literally thousands of Biblical fragments and ancient Jewish documents were found, which added greatly to the understanding of these religions. Today, the shores of the Dead Sea contain popular beaches, resorts, and spas.


The Dead Sea

The Dead Sea, also called the Salt Sea, is a salt lake bordering Jordan to the east, and Israel to the west. Its surface and shores are 427 metres below sea level, Earth’s lowest elevation on land. The Dead Sea is 306 m deep, the deepest hypersaline lake in the world. With 34.2% salinity (in 2011), it is also one of the world’s saltiest bodies of water, though Lake Vanda in Antarctica (35%), Lake Assal (Djibouti) (34.8%), Lagoon Garabogazköl in the Caspian Sea (up to 35%) and some hypersaline ponds and lakes of the McMurdo Dry Valleys in Antarctica (such as Don Juan Pond (44%) 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 50 kilometres long and 15 kilometres 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 fertilisers. People also use the salt and the minerals from the Dead Sea to create cosmetics and herbal sachets.

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

More information is available on Wikipedia

The Dead Sea
Overlay image (Before and After)

Today we feature the Dead Sea, situated between Israel and Jordan, and forming part of the border between the two countries. The Dead Sea is fed mainly by the Jordan River, which enters the lake from the north. Several smaller streams also enter the sea, chiefly from the east. The lake has no outlet, and the heavy inflow of fresh water is carried off solely by evaporation, which is rapid in the hot desert climate. Due to large-scale projects by Israel and Jordan to divert water from the Jordan River for irrigation and other water needs, the surface of the Dead Sea has been dropping dangerously for at least the past 50 years. Environmental groups, led by Friends of the Earth, launched a «Let the Dead Sea Live» campaign in 2001 to preserve the lake and its unique environmental qualities. In September 2002 Israel and Jordan agreed to construct a 320-km pipeline that would link the Dead Sea with the Gulf of Aqaba, to slow down the process of evaporation of the lake’s waters. If the shrinkage is allowed to continue, it is likely that the Dead Sea might disappear altogether by 2050.

These images acquired by the Landsat 5 and 8 satellites both acquired in October have a time window of acquisition (before / after) of thirty years and aim to show the difference of the coasts of the Dead Sea from 1984 until today. In fact the two images show how the lake, especially on the south coast, has suffered a significant reduction in the amount of water over the past thirty years.

Another aim of these images is to promote the opportunity to download Landsat data through the ESA portals, where images captured every day are made available in near real time to the users and the scientific community.

Landsat full resolution data products are freely available for immediate download at:

  • LANDSAT-8 portal
  • LANDSAT 1-7 portal

Dead Sea 2014Dead Sea 1984

Technical Information of original image
Product:Geo Tiff format
Satellite/Sensor:Landsat 5 TM and Landsat 8 OLI
Resolution:30 metres
Coverage:180 x 180 KM
Acq. Date:24 October 1984 and 27 October 2014
Band Combination used to create this image:3, 2, 1 ( R — G — B ) and 4, 3, 2 ( R — G — B ) Visible colour
Map of area

What is the importance of the Dead Sea in the Bible?

The Dead Sea is a large body of salt water on the southern end of the Jordan River. Cited sixteen times in the Bible, the Dead Sea is mentioned primarily to describe the borders of the Promised Land.

The Dead Sea is known by a few different names in the Bible, including the Salt Sea (Genesis 14:3; Numbers 34:3, 12; Deuteronomy 3:17; Joshua 3:16; 12:3), the Sea of the Arabah (Deuteronomy 3:17; 4:49; Joshua 3:16; 2 Kings 14:25), and the Eastern Sea (Ezekiel 47:18; Zechariah 14:8). It was called the Salt Sea for its unusually high salinity. The name Sea of the Arabah was given for its location in the Arabah Valley. In Hebrew, arabah means “a wasteland” or “barren district.” And the name Eastern Sea originated from the Dead Sea’s position on the eastern boundary of the land of Israel.

Only in Genesis 14:3 is the Dead Sea referred to as a location. In all other instances, it is used to designate a border for the land of Israel. Thus, the Dead Sea was likely considered more of a territorial boundary line than a destination for the people of the Bible. Nevertheless, several noteworthy biblical settlements were positioned on the shores of the Dead Sea, including Masada, En Gedi, and Qumran.

The Dead Sea is located 16 miles directly east of Jerusalem. A long and narrow oblong, the sea, in Bible times, measured a little over 50 miles from north to south and about 11 miles wide at its broadest point. The Dead Sea lies within the great trough of the Jordan Valley, also known as the Rift Valley, which forms part of the longest and deepest crack in the earth’s crust. At approximately 1,300 feet (400 meters) below sea level, the Dead Sea sits at the lowest point of the earth’s surface.

Fed mainly by the Jordan River and a few smaller streams and rivers, the Dead Sea receives an average of six or seven million tons of daily inflow with no outlet for the water except through evaporation. The extreme heat and dry conditions of the region produce an exceptionally high rate of evaporation. Even with no outflow of water, the Dead Sea’s surface rises no more than 10 to 15 feet a day.

The waters that feed the Dead Sea contain an unusually high salt content (approximately 26 percent), making it the world’s most saline body of water, with almost five times the level of salt concentration of the ocean (on average 3.5 percent). With such high salinity, no marine life can live in the Dead Sea.

Even with its inability to sustain life, the Dead Sea provided a valuable commodity for trading in ancient times—salt. The sea was also known for producing bitumen, a natural petroleum product similar to asphalt, prized for its waterproofing properties. Historians have suggested that Cleopatra’s ambition to rule the Dead Sea region was motivated by her desire to control the bitumen trade.

Biblical archaeologists believe the destruction of Sodom and Gomorrah in Genesis 18—19 took place in the vicinity of the Dead Sea. Some believe that Sodom and Gomorrah lie underneath the Dead Sea. Exactly how God destroyed these cities is still debated. Some theorize God used a volcanic eruption or a spontaneous explosion of subsurface pockets of bituminous soil. Curiously, at the southeast corner of the Dead Sea is a salt rock plug known today as Mount Sodom. On its slopes, which are formed by a combination of gypsum, salt, limestone, and chalk, can be seen strange formations of salt, like pillars. These pillars are often pointed out to tourists by the nickname “Lot’s wife” (see Genesis 19:26).

When David fled from King Saul, he found a place of refuge on the western shore of the Dead Sea in the town of En Gedi. In contrast to the lifeless nature of the Dead Sea, En Gedi is an oasis full of fresh flowing springs, fine dates, aromatic and medicinal plants, and semitropical vegetation.

The prophet Ezekiel foresaw a time when the Dead Sea’s toxic waters would be transformed into a fresh River of Life flowing from the throne of God: “This water flows toward the eastern region and goes down into the Arabah, where it enters the Dead Sea. When it empties into the sea, the salty water there becomes fresh. Swarms of living creatures will live wherever the river flows. There will be large numbers of fish, because this water flows there and makes the salt water fresh; so where the river flows everything will live. Fishermen will stand along the shore; from En Gedi to En Eglaim there will be places for spreading nets. The fish will be of many kinds—like the fish of the Mediterranean Sea. . . . Fruit trees of all kinds will grow on both banks of the river. Their leaves will not wither, nor will their fruit fail. Every month they will bear fruit, because the water from the sanctuary flows to them. Their fruit will serve for food and their leaves for healing” (Ezekiel 47:8–12).

In recent times the Dead Sea has been shrinking because its waters are evaporating faster than the inflow from the Jordan and other streams can replenish. In the last 40 years or so, the sea has lost about 30 percent of its area and has divided into two basins. The shallow southern basin is used primarily for the mining of Dead Sea minerals.

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