Scientists discover vast undersea freshwater reserves

December 5, 2013
Australian researchers say they have identified vast reserves of fresh water trapped beneath the ocean floor off Australia, China, North American and South America

Australian researchers said Thursday they had established the existence of vast freshwater reserves trapped beneath the ocean floor which could sustain future generations as current sources dwindle.

Lead author Vincent Post, from Australia's Flinders University, said that an estimated 500,000 cubic kilometres (120,000 cubic miles) of low-salinity had been found buried beneath the seabed on continental shelves off Australia, China, North America and South Africa.

"The volume of this water resource is a hundred times greater than the amount we've extracted from the Earth's sub-surface in the past century since 1900," said Post of the study, published in the latest edition of Nature.

"Freshwater on our planet is increasingly under stress and strain so the discovery of significant new stores off the coast is very exciting.

"It means that more options can be considered to help reduce the impact of droughts and continental water shortages."

UN Water, the United Nations' water agency, estimates that water use has been growing at more than twice the rate of population in the last century due to demands such as irrigated agriculture and meat production.

More than 40 percent of the world's population already live in conditions of . By 2030, UN Water estimates that 47 percent of people will exist under high water stress.

Post said his team's findings were drawn from a review of seafloor water studies done for scientific or oil and gas exploration purposes.

"By combining all this information we've demonstrated that the freshwater below the seafloor is a common finding, and not some anomaly that only occurs under very special circumstances," he told AFP.

The deposits were formed over hundreds of thousands of years in the past, when the was much lower and areas now under the ocean were exposed to rainfall which was absorbed into the underlying water table.

When the polar icecaps started melting about 20,000 years ago these coastlines disappeared under water, but their aquifers remain intact—protected by layers of clay and sediment.

Post said the deposits were comparable with the bore basins currently relied upon by much of the world for drinking water and would cost much less than seawater to desalinate.

Drilling for the water would be expensive, and Post said great care would have to be taken not to contaminate the aquifers.

He warned that they were a precious resource.

"We should use them carefully: once gone, they won't be replenished until the sea level drops again, which is not likely to happen for a very long time," Post said.

Explore further: Limestone caves provide measure of Australian groundwater

More information: "Offshore fresh groundwater reserves as a global phenomenon" by Vincent E.A. Post, Jacobus Groen, Henk Kooi, Mark Person, Shemin Ge and W. Mike Edmunds: … ull/nature12858.html

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1 / 5 (5) Dec 05, 2013
"You mean, the stuff in toilets?!?" -Idiocracy

3 / 5 (1) Dec 05, 2013
Well, that's good, but not enough on the human civilization's scale. What we need are recycling units that can be used individually, more like Dune's stillsuits. Also technology to extract water from scarce sources like air from the desert and enclosed spaces. These can prepare us for an environment with 10 times today's population and also for outer space living. This is fundamental in order to ensure further mankind's progress, one of its few renewable resources.
not rated yet Dec 05, 2013
"And underneath the bubble: ten thousand years of fresh air"
"The way he runs things it won't last a hundred"
--Space Balls

I dunno why that comes to mind.
2.6 / 5 (5) Dec 06, 2013
Well, that's good, but not enough on the human civilization's scale. What we need are recycling units that can be used individually, more like Dune's stillsuits
One reason I didnt like dune; these were disgusting. No, what we need are cheap new sources of energy for desalination and distribution. Speaking of which, wheres zephyr been? Home to tralfamador for the holidays?
1 / 5 (5) Dec 07, 2013
The exponential function meets another finite resource. Which will win?
The exponential function must be pitted against an infinite resource- Space, the Cosmos, the Void.
Where darkness reigns supreme. Darkness will triumph, one way or the other.
2 / 5 (4) Dec 07, 2013
Well, that's good, but not enough on the human civilization's scale. What we need are...

The main technology that is lacking is cheap, low-consequence electric power. Sure there's still room for improvement in filtration, seals, catalysts, etc but cheaper, cleaner electric power improves all the already existing tech. Energy input is the largest cost in desalination of seawater. We can already desalinate seawater, it's just expensive. Another issue is just time. It takes time to come up with and build big engineering projects.

It sounds like this water will still require significant processing, but if it only bought the human race 100 years, that should probably be enough time to improve tech, coordination, identify more resources and make better use of them, etc.
1.8 / 5 (5) Dec 08, 2013
which could sustain future generations as current sources dwindle.

what utterly mindless twaddle.

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