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Huge Pool of Ice-Free Water Discovered Under Greenland Ice
The BBC reports that researchers have discovered a huge pool of meltwater beneath Greenland's ice sheet, trapped "in the air space between particles of ice, similar to the way that fruit juice stays liquid in a slush drink."
From the article, based on research published in Nature Geoscience (abstract): "The scientists say the water is prevented from freezing by the large amounts of snow that fall on the surface of the ice sheet late in the summer. This insulates the water from the air temperatures which are below freezing, allowing the water to persist as liquid all year long. Other researchers believe this discovery may help explain disparities between projections of mass loss by climate models and observations from satellites."
Given our current level of technology, I'm always amazed when we discover large scale things like this. We have out cities mapped and photographed down to the meter, but we keep finding things like this.
Sorta like the bulk of the oceans remain liquid under the ice that forms in the northern oceans.
Great minds think alike; fools seldom differ.
...said the physics teacher.
Under pressure, the freezing point of water is lowered. The more pressure, the lower the ice point. To demonstrate:
Assume that a container is indestructible (let's say, a sphere with a perfect seal). It is full of water with no gas in solution or loose in bubbles or anything like that. Just pure water. Now, stick it in a deep freeze. Wait.
Water has the odd property of expanding at around 4C at normal (sea level) pressure. By the time it freezes at 0C under those same pressure conditions, it has expanded to fill 1/8 more volume than it did as a liquid. This is why icebergs float. This is why distilled water ice cubes also float. The liquid water does its thing and... you know the rest. Titanic.
The water in the sphere is prevented from freezing for the simple reason that it has nowhere to go. It has no space to expand into. If it cannot expand, it cannot freeze. How low can you go? I have no idea, having no access to magnetocaloric equipment. But I daresay, you wouldn't meet the conditions required to get the volume of water to contract to the point where it can solidify in the available space, outside of a suitably equipped laboratory or in the shadow of an outer planet.
Further reading suggests temperatures approaching/lower than about 70K (-203C) to achieve this. Further reading.
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
Other researchers believe this discovery may help explain disparities between projections of mass loss by climate models and observations from satellites
Or maybe not. For all we know that slush has been there since the last ice age.
So there was a discrepancy between prediction and observation for the AGW model. Why haven't we heard about that before? Only now that the observations are consistent with theory do we find out about it. Yet more evidence that climate scientists are not real scientists.
What makes you think that scientists have hidden this discrepancy? They haven't, and every anti-AGW promoter has been shouting it from the rooftops (while they ignore or misrepresent all the evidence that supports AGW.)
Some privacy policy Slashdot.
If that water underneath the ice made it possible that the entire sheet of ice could slide off in one go, that would make projections of melting time somewhat irrelevant. Might just nead a bit of an earthquake to get things moving...
You mean, a thing that there is plenty of that we're constantly being told is just years away from being completely gone?
Are there really people denying "climate change"? It's a pretty accepted thing. Maybe not that it is due to man, but that there is change, sure. Of course, we also can't decide if the change is global *warming* or global *cooling*. It was only a couple decades or so ago that we were told pollution was sending us over the edge of unavoidable ice-ages.
I suppose you can sort of understand their skepticism. If I was born in 1990 and all I had ever heard was "global warming global warming AND IT IS ALL OUR FAULT!", I'd be terrified, too. If I was born in 1970 and had lived through "global cooling global cooling AND ITS ALL OUR FAULT!", I would probably be extremely skeptical of the claims, since I'd have been alive long enough to remember it the first time around.
There's lots of fresh water on the planet (including all the fresh water stored as ice). The problem is getting to a place where it's useful. Most places have to make do with the fresh water that's available locally. A notable exception being Southern California which imports water from the north and from the Colorado River. I doubt you'll find knowledgeable people saying fresh water would be completely gone (except perhaps for some overtaxed aquifers). Instead they are saying there will be more demand for fresh water than there is supply available to fill that demand in the future. Getting fresh water from Greenland to any place useful would be difficult and expensive.
And yet despite the fact that the global cooling story made the covers of Time and Newsweek in the mid-70's, between 1965 and 1979 there were 6 times as many papers published on global warming from CO2 increases than global cooling in the scientific literature. I was born in 1952 and I don't remember being very alarmed by global cooling in the 1970's.
Exactly, it constantly amazes me that some of the posters here who rely on science in almost every aspect of their lives can be convinced by either the media or their own self interest to deny reality with the thoroughly debunked skeptics arguments. There's a sucker born every minute apparently.
There is only one thing to do.
Pump it out, bottle it, and sell it.
Then use the resulting cavern to hold raw sewage. Maybe with a little radioactive waste thrown in for good measure.
Sleep your way to a whiter smile...date a dentist!
They are unable to predict the future though, and always have been.
That is a pretty unsupportable statement considering that the scientists are well aware of how much certainty their models have, and so give a large error range such that it was nearly impossible to get it wrong. Your claim that they all have been falsified by observations is a complete lie.
No it is just an obvious ploy from those LiBeRaL scientists to back track on their global warming "Science" so they can continue to leach off of hard working Americans money, so they work rich and without impunity in the Education Commune.
Hey that sounds pretty good, I could be a conservative radio host. I don't need to agree with, or have any fact to back up the stuff I spew, just a sweet gig.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
In this case it's probably just you. Rather than attack my sources why don't you attack my information?
For simple noncontroversial things like the definition of the term "firn" Wikipedia is about as good as anything. I felt the need to provide the reference since firn is not a common word in everyday conversation.
After spending a half hour searching for information about how deep the snow had to get before it became glacial ice I found lots of papers and such that said, "When the snow gets deep enough it compacts to ice from the weight of snow above it" but the National Geographic article was the first one I found that put an actual number on it so I went with it. Based on past experience I expect NG is better than the average web page in this regard.