Vast Freshwater Reserves Found Beneath the Oceans

http://www.sciencedaily.com/releases/2013/12/131208085304.htm

by mankypro • 13 years ago

48 40 13 years ago

leeoniya3• 13 years ago

hmmm, the ocean's pretty heavy. i wonder what extracting an incompressible fluid from the seafloor's support structure will do to weaken it. will they fill it with saltwater instead?

i guess it shouldnt be much different than oil drilling :\

Danieru• 13 years ago

This might be off-topic but water is in-fact compressible: http://en.wikipedia.org/wiki/Properties_of_water#Compressibi...

leeoniya3• 13 years ago

not off-topic, maybe just a bit too pedantic.

"The low compressibility of water means that even in the deep oceans at 4 km depth, where pressures are 40 MPa, there is only a 1.8% decrease in volume."

also: http://en.wikipedia.org/wiki/Oil_platform#Deepest_oil_platfo...

jbattle• 13 years ago

Getting further afield, water's density actually changes considerably with a change in temperature. http://en.wikipedia.org/wiki/Properties_of_water#Density_of_...

I'm not sure how common this is but I know Lake Michigan goes through an annual cycle where the water alternately mixes and segregates (by temperature). In the summer, the warm, less dense water rises to the top and stays there. In the winter, very cold water is actually lighter than slightly warmer water and a similar stratification happens. In spring and autumn the water temperatures near the surface equalize with water deeper in the lake and much if not all of the lake water circulates ("turns over").

http://www.lakeaccess.org/ecology/lakeecologyprim4.html

teh_klev• 13 years ago

Water is compressible, which is why we don't use it for brake fluid and safety critical hydraulic applications.

lostlogin2• 13 years ago

Is it that or its conversion to steam at a relatively low temperature or its ability to rust out the brakes?

mankypro• 13 years ago

From a purely practical point of view, isn't the "community at large" worried about the "rising" sea levels? If we took the fresh water from the aquifers, then refilled them with sea water, presumably that would put a dent in the rising sea levels? I know, I know...just trying to be pragmatic.

mnw21cam• 13 years ago

http://what-if.xkcd.com/33/ shows just how much the sea level would drop if all ships disappeared. That's probably more volume than you're likely to drink from an aquifer. There's a reason for the saying "a drop in the ocean".

Besides, once we had used that water, it would run back into the sea.

nocoment• 13 years ago

will they fill it with saltwater instead?

Push CO2, get back carbonated water? Then it is $1/liter + carbon credits for what doesn't come back up. :)

HCIdivision17• 13 years ago

Bizarrely, that could be immensely dangerous. There have been a few lakes with large quantities of dissolved co2 that have critically released that gas when jostled, either by vibration or temperature shock (of a couple degrees leading to mixing). There's no telling if it would happen in the ocean, but if currents are slow, a cascade of gas rushing to the surface could be pretty bad.

[0] https://en.m.wikipedia.org/wiki/Lake_nyos

ds9• 13 years ago

Upon reading the headline I too immediately wondered, if the fresh water is sucked out, wouldn't the ocean collapse the roof of the space?

Other posters here are saying, replace it with salt water or CO2. The CO2 idea was answered. As for the "swap seawater for fresh" idea, as soon as you put a significant amount of sea water in there, you no longer have fresh water coming out! The only way to get a freshwater supply from this would be to take all it out before replacing, but then you have the "supporting the ocean bottom" problem in the interim.

mkingston3• 13 years ago

Actually, the mixing properties are incredibly important. Even under the ocean much oil isn't in big cavities, it's in porous rock. If this is the case with fresh water, the structure containing the fresh water might actually sufficiently support the salt water on top of it as we reduce the internal pressure when extracting fresh water.

Even if not, we can drill and extract fresh water at one end and pump in salt water at the other, until the water we get out becomes too saline. In porous rock the mix rate would be quite low; kind of like pumping salt water into a sponge at one end and extracting the fresh water at the other end (for a while).

This is quite a common practice in the oil industry.

Finally, salt water is more dense than fresh water. If these reservoirs underwater actually are big cavities; we can just pump salt water in the bottom and pump fresh water out the top.

NB: When I say "we can just", I mean, take a wild best guess about where the bottom and top of the well is based on crazy amounts of uncertain data extracted on a well-by-well basis.

devindotcom• 13 years ago

Good, now we can put off thinking about conservation yet again! Our great-grandchildren will have plenty of time to think of something.

astrodust• 13 years ago

Carbon credits today, water credits tomorrow.

kamjam2• 13 years ago

Soon to be followed by shale fracking for water.

0xdeadbeefbabe• 13 years ago

Grandchildren credits too.

mkingston3• 13 years ago

Possibly good indeed. Spending that money now against our great-grandchildren's future earnings might not be in their best interest.

Besides, don't we have enough on our plate with CO2? Sure, theoretically we could focus on both, but we seem to be doing a pretty bad job with the CO2.

Also, I'd probably rather drain these non-renewable fresh-water sources and spend the saved money on improving the quality of life of those who need it most (developing world), all the while with a long-term focus on better energy for desalination/reuse. To be fair, though, this entire paragraph is a pipe-dream.

clord• 13 years ago

We're contemplating going after harder-to-get fossil water because the easy stuff is depleted and can no longer keep up. Sounds like the situation we're in with oil.

In the case of water, which replenishes, the 'production cycle' is actually the global fresh-water cycle. If we dirty all of the fresh water faster than the earth can clean it, we're going to have to start drilling for the fossil stuff in hard-to-reach places. It's strange to think there would be drilling rigs in the ocean with people risking their lives and taking danger pay... for water. It raises a question in my mind: affordability. Who is going to be able to afford to buy all their water like this?

It's the next step now that there are several major rivers no longer reaching the ocean.

eru2• 13 years ago

Who is going to be able to afford to buy all their water like this?

The price of water can never really climb above the price of desalination.

mkingston3• 13 years ago

Danger pay is not nearly as true as it used to be[1]. Though I guess perception-of-danger pay might still be in play.

1. http://www.forbes.com/sites/robertbradley/2013/03/25/oil-gas... (honestly, I can't really be bothered tracking down the BLS reports.. this is the first article I found with any numbers and it reinforces what I've been told by a friend in the industry)

ryan_j_naughton2• 13 years ago

Regarding criticism that this isn't renewable and delays the move to renewable resources:

At the rate we are damming rivers, we will destroy many river ecosystems. This new potable water source seems less harmful than dams and could be a bridge until the energy costs of desalination are low enough.

If this discovery spurs investment in desalination (since this is simply cheaper desalination due to the lower salinity) that would be an added benefit as it would accelerate the move toward desalination.

Perhaps we could skip the dams entirely (which though seemingly renewable from a water perspective, are highly destructive to river ecosystems).

toomuchtodo• 13 years ago

We're already on the path to extremely cheap energy with solar and wind. Shouldn't we continue to drive down the cost of power by ramping up more investment in these energy source? Nuclear as well, as long as its managed properly.

schiffern2• 13 years ago

until the energy costs of desalination are low enough.

Really? You think desalination is the ultimate goal? I much prefer free, ecosystem-provided desalination (aka rooftop rain-water harvesting).

As for agricultural water use, I highly suggest picking up a copy of P.A. Yeoman's classic Water For Every Farm. It details how proper runoff management, evaporation control, and correctly-scaled earthworks can provide reliable water availability with near-zero energy inputs [other than the sun, of course].

As for dams, it's not as simple as "all dams are bad". Oversized dams that are out of scale with the local hydrology are the problem.

But, I guess some people would prefer to re-invent the Earth's water cycle!

ryan_j_naughton2• 13 years ago

I agree that not all dams are bad. The real issue with dams is the scale. We are on track to dam the majority of the world's rivers over the next 50 years, and this will have significant effects on river and coastal ecosystems.

> I much prefer free, ecosystem-provided desalination (aka rooftop rain-water harvesting).

I agree; however, this is not an infinite supply. Taking water from rivers is effectively a form of this and it is lower cost than many other "free, ecosystem-provided desalination" since the water has already been collected into a river due to gravity and land contours. As we remove water from these 'free' sources, we are depriving an ecosystem of that water.

The worst case scenario is something like the Aral Sea http://en.wikipedia.org/wiki/Aral_Sea

InclinedPlane• 13 years ago

Whether you're desalinating or just doing runoff management you're mucking about with the Earth's water cycle either way.

The bigger issue is actually just using waste water recycling, which is today a feasible proposition but for public perception.

TrainedMonkey• 13 years ago

Newsflash - vast freshwater resources had been found sitting in form of ice on planetary caps. Those vast supplies of water are expected to last till 2030.

On a serious note, this could be big. Imagine oil like drilling platforms that pump water instead. Now we only need to figure out how economical this is.

sanskritabelt• 13 years ago

I guess there really is water at the bottom of the ocean.

bigtech• 13 years ago

Once in a lifetime, water flowing underground.

programminggeek• 13 years ago

Well, this is about the time we see crazy theories about some crazy civilizations living inside the planet with all this fresh water and heat freely available to them....

ryanjodonnell• 13 years ago

Getting the water out of reserves beneath the ocean sounds expensive - I wonder how it stacks up energy wise vs desalination of ocean water.

ironmanjakarta• 13 years ago

Govt is the cause of water shortages

http://www.lewrockwell.com/2013/10/ryan-mcmaken/socialist-wa...

Vast Freshwater Reserves Found Beneath the Oceans

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