Dead Sea drilling reveals ‘epic’ droughts throughout history
Scientists from Columbia University use geological sample to reveal arid spells that lasted for decades or centuries, thousands of years ago
Scientists who drilled 450 meters (1,500 feet) into the floor of the Dead Sea announced this week that the region may have been affected by “epic” centuries-long droughts, much worse than researchers previously believed.
The study, led by Columbia University’s Lamont-Doherty Earth Observatory and scientists from six countries, examined a geological sample revealing more than 200,000 years of climate history in the Dead Sea region.
“All the observations show this region is one of those most affected by modern climate change, and it’s predicted to get drier,” said Yael Kiro, the lead author and a geochemist at the Columbia observatory.“What we showed is that even under natural conditions, it can become much drier than predicted by any of our models.”
The scientists drilled the core sample in 2010 in around-the-clock drilling that lasted for 40 days and 40 nights, but only released their findings regarding drought this week in the journal Earth and Planetary Science Letters.
The scientists studied the thickness of the salt layers, as well as liquid bubbles trapped in the layers of salt, to determine precipitation and runoff to the Dead Sea, uncovering some alarming trends.
According to the study, the region experienced two major drought periods when rainfall and runoff patterns were at some points less than 20% of the average rainfall for the 20th century.
Generally, salt accumulates at approximately 1.2 centimeters (0.5 inches) per year, after which a layer of mud is deposited during the rainy season. But in some places, the salt layers were 90 meters (300 feet) thick – indicating an epic drought with little to no rain.
These “epic” droughts lasted for decades or even centuries. There were at least two indications of these massive droughts, one dating from 115,000 to 130,000 years ago, and the other one from 6,000 to 10,000 years ago.
According to researchers, rainfall has declined about 10 percent since 1950, and existing climate models say it could sink another 20 percent this century. Long droughts can have catastrophic effects on the region. Many people blame a 1998-2012 drought in Syria, the worst in 900 years, as one of the catalysts for the current civil war.
Residents around the Dead Sea are trying to find new ways to deal with the reality of the shrinking Dead Sea, as millions of people in Syria, Jordan, and Israel siphon out the water to use for agriculture and consumption. The Dead Sea is shrinking at more than 1 meter (3 feet) per year, creating more than 5,000 sinkholes along the shore as the water recedes.
Currently, the Sea of Galilee, which is the main source for the Dead Sea runoff, is at its lowest level in more than a century. Israel’s most important natural water source — also known at Lake Kinneret — received just 10 percent of its average rainfall for February, the driest February in the area since record-keeping began.
