The mysteries of the Dead Sea

The landlocked Dead Sea of the Middle East is Earth’s lowest spot on land. The current Dead Sea shoreline lies about 1,300 feet below sea level but it’s dropping at a rate of about 4 feet per year. Yael Kiro is Geochemist at Columbia University and is using layers of salt from the seabed to study the significance of this change.

TRANSCRIPT

The landlocked Dead Sea of the Middle East is Earth's lowest spot on land.

The current Dead Sea shoreline lies about 1,300 feet below sea level, but it's dropping at a rate of about 4 feet per year.

Yael Kiro is a geochemist at Columbia University, and is using layers of salt from the sea bed to study the significance of this change.

This segment is part of our ongoing series of reports, 'Peril & Promise: The Challenge of Climate Change.'

So thanks for joining us.

Thank you.

What do we learn from digging down into a sea bed, well, mostly a salt bed?

So, we can learn several things.

We learn a lot about climate.

We can learn about past earthquakes.

I'm specifically reconstructing a rainfall during the most dry periods, during the time of the drilling.

Okay, so this piece of salt that we have here.

Mm-hmm.

It's a crystalline form.

How old is this?

This is around 120,000 years old.

120,000 years old.

So what do you learn from seeing that piece of salt about the climate that was happening at the time at the Dead Sea?

So, we know what is the amount of salt that we have in the drilling.

And inside the salt, we have these small bubbles of liquid that trapped the water of the lake during that time.

And we can analyze the composition, what is the dissolved salts inside these small bubbles.

So we use this, and how much salt do we have, and reconstruct how much fresh water flowed into the lake in the past, and then we know what was the past climate and what was the rainfall.

So, what surprised you?

Did you think that there were droughts as significant as the ones that history sort of revealed?

We knew that there was a significant decrease in precipitation and it was a drier period, but now we were able to quantify.

And I didn't think that it would be as much low than what it is now and what is expected in the future.

If we're doing things now to kind of accelerate the warming of the planet, compare that to 120,000 years ago or whenever it was, where there were warm periods as well, but just not humans accelerating it.

Yeah, so, today, we see the lake levels dropping and salt is forming in the lake due to anthropogenic influence.

But what we show... We are talking about the water that is available to people in the system.

So today, all of the water that flows into the Dead Sea is used by the countries around the Dead Sea -- by Israel, by Lebanon, by Syria, by Palestine.

And we are showing that the water stress may be even larger in the future because of warming.

Models, for example, are expecting that there will be a decrease by 20% in water availability, but what we show that under natural conditions, it can go down by 80% due to warming.

So we have here an independent research that may show that things may be even worse than what we think it would be in the future.

So even with no humans around, it had reached bottom with 80% below levels.

Yeah.

And here we are now, with humans fighting over that limited resource of water, and they're predicting it can go down 20 percent.

But you're saying it could get much, much worse.

Yes.

How does this data compare to other climate-change models that we have?

I mean, when you go get a core sample, this isn't the Arctic, the Antarctic.

But you are getting a moment in time.

Yes, so we have different climate records.

We have marine records or ice core records, and each one of these records are showing different records.

For example, temperature, or concentration of CO2 in the atmosphere.

So what we see here is the regional climate in the Middle East, and usually terrestrial records, we use them in order to reconstruct precipitation.

With this data, do you go back to the presidents or the heads of these countries and say, 'Here's something that we've just discovered, that your water drought situation could be much worse.'

Do they listen to the scientists that go out and do these...?

We hope that some policy people or environmental organizations will take this into account.

But I think this region is sensitive anyway, and there is a lot of effort by local scientists and by decision makers and environmental organizations to deal with all of the environmental issues and the water stress in this region.

Okay, Yael Kiro, Associate Research Scientist of Geochemistry at Columbia, thanks for joining us.

Thank you very much.