Drilling below the sea floor shows a roller-coaster ride for the region’s climate.
By Zafrir Rinat

The Dead Sea may be drying up, but research by Israeli scientists and colleagues abroad shows that the water has risen and fallen by hundreds of meters over the past 200,000 years.

The goal is to study the region’s climactic history and forecast possible changes in the future. The project should also provide rich information on the region’s seismic history and conditions in the area that influenced human development.
Dead Sea – Daniel Bar-On – 14112011

Drilling at the Dead Sea last year. Research shows that during the last Ice Age, sea level was 250 meters higher than its current level.
Photo by: Daniel Bar-On

The preliminary findings come from excavations at the seafloor. The data confirm previous studies that claimed that the sea isn’t really dead and that bacteria have survived in the extreme salty conditions.

The International Continental Scientific Drilling Program has funded the excavations. The drilling started a year ago and lasted four months. The study involved institutions from the United States and Europe; it was led by Prof. Zvi Ben Avraham, head of the Minerva Dead Sea Research Center at Tel Aviv University, and Dr. Moti Stein of the Geological Survey at the National Infrastructure Ministry.

Testing in Berlin

At the center of the sea, the researches drilled 460 meters below the seafloor and extracted salt and other materials that had settled there as much as 200,000 years ago. Plastic tubes containing centuries of climactic history are now in Germany for testing.

In laboratories in Potsdam near Berlin, Israeli and German scientists are examining the stuff in the tubes.

“What we have found are several layers of salt that bear witness to a period of dryness and very little rainfall at the Dead Sea’s drainage basin, and this caused the sea to recede and salt to gather at its center,” says Stein.

The researchers have found stone fragments that show that the sea was low – the evidence suggests that the coast once receded significantly and the sea came close to drying up. One theory is that this period occurred about 120,000 years ago, with another period of extreme dryness taking place 13,000 years ago.

“We believe that this [first] period of dryness involved a climactic catastrophe, one that influenced human development in this region,” says Stein.

During the last ice age, for example, the sea was 250 meters higher than today. When the sea rose during rainy periods, it spread throughout the Jordan Valley and approached Lake Kinneret in the north.

Analysis of drilling samples reveals the existence of microorganisms at about a hundred meters below the seafloor. Meanwhile, in a recent study, scientists from Germany and Ben-Gurion University of the Negev dived into the sea and found bacteria populations in the sea’s freshwater inlets.

The Dead Sea has receded in recent years at a meter a year. Unlike past eras, the main reason is that water that once flowed to the sea, mainly from the Jordan River, is diverted for use in Israel, Syria, Lebanon and Jordan.

The World Bank plans to release a study soon on the plausibility of a project to bring water from Eilat Bay to the Dead Sea via Jordan. This would help prevent the sea from drying up.

http://www.haaretz.com/print-edition/news/dead-sea-drying-up-that-s-so-120-000-years-ago-1.395416