Name: Scientists Use Drones to Track Dead Sea Sinkholes
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The Dead Sea is home to some 6,000 sinkholes—and as its water keeps receding, more will form.

How do sinkholes come to be, and how do researchers study them?

Scientists Use Drones to Track Dead Sea Sinkholes

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The Dead Sea is home to some 6,000 sinkholes—and as its water keeps receding, more will form.

How do sinkholes come to be, and how do researchers study them?

Planet Earth

Scientists Use Drones to Track Dead Sea SinkholesPublished: September 3, 2019Onscreen: Back in the 1960s, the Dead Sea was almost up to the road. Now, in some areas it’s a mile away. And as the water declines, the beach has become inundated with sinkholes: 6,000 and counting.Gideon Hadas: It’s like the craters on the moon, but here, it’s not the moon. This is a dying sea.Onscreen: Geohydrologist Carmit Ish-Shalom is trying to predict when and where the next sinkhole will form. For years, she measured sinkholes the old fashioned way, with a measuring tape.Carmit Ish-Shalom: It’s very, very sophisticated: just throw it down there.Onscreen: But for areas where sinkholes are just beginning to develop, she uses a drone.Ish-Shalom: We can see the whole sinkhole from above, and we can see how big it is. Each month, we are monitoring them, trying to see the changes in the size, in the depth, how fast they form. There’s many kinds of sinkholes in the world; the kind that we have here in the Dead Sea is very unique.Onscreen: Most sinkholes form in rock, like limestone, but here at the Dead Sea they’re caused by salt. As the sea declines, an underground layer of dry salt is left behind. Fresh water, like in winter flash floods, saturates that salt, which quickly dissolves, creating an underground cavity. Over time, it grows bigger, until, suddenly, without warning, the earth above it caves in.While the cause of Dead Sea sinkholes is well known, after 20 years of careful measurement, there is still no detectable pattern for sinkhole formation. Each sinkhole seems to follow its own rules.Ish-Shalom: We don’t really know when the next one will form—next year or maybe two years from now or maybe tomorrow.

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Scientists Use Drones to Track Dead Sea Sinkholes

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Saving the Dead Sea

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