Posted on 03/06/2011 9:19:47 AM PST by smokingfrog
*** Ice sheet structure far different than thought complicating rising-sea scenarios ***
Knowing how the massive ice sheets atop Antarctica and Greenland work is key to predicting how global warming could raise sea levels and flood coastal cities. But a new study upends what scientists thought they knew. It turns out its not just ancient snow that makes up the ice sheets, but water deep under the sheets also thaws and refreezes over time.
To put it in non-scientific terms, lead scientist Robin Bell told msnbc.com, the study redefines "how squishy" the base of ice sheets can be. "This matters to how fast ice will flow and how fast ice sheets will change."
"It also means that ice sheet models are not correct," she said, comparing it to "trying to figure out how a car will drive but forgetting to add the tires. The performance will be very different if you are driving on the rims."
Reporting in this week's issue of the peer-reviewed journal Science, Bell and his team described how ice-penetrating radar peeled back two miles of ice a million years old in the center of Antarctica.
The images show that refrozen ice makes up 24 percent of an area known as Dome A, a 13,800-foot-high plateau roughly the size of California. Much of the sheet and refrozen ice lies atop an underground mountain range.
Ice from that area "drains into all the major ice shelves of Antarctica," the researchers wrote in their study. "Processes occurring in the Dome A region have the potential to affect the majority of East Antarctica."
While the field work was far inland, Bell believes the same will hold true along the edges of the icy continent. (cont.)
(Excerpt) Read more at msnbc.msn.com ...
Bologna! The science is settled! Algore told me so!
If they are “just now” discovering this, how can they know whether its normal or not? Was it more or less 100, 500, 1000 years ago?
‘Squishy’?? In the Scientific Lexicon, is that somewhere close to ‘Icky’???
There needs to be a worldwide law that we never set any political policy based on scientific hypotheses. You can always find something later that contradicts prior data, or misread the data, or have incorrect data due to deliberate or indeliberate calibration and/or placement issues.
Oh btw eggs are good again.
Well, our coastal cities aren’t yet underwater like Algore said they’d be so somebody had to find an inconvenient excuse.
Nothing that comes out of a hen’s butt is ever “good”.
Funny thing, I did a empirical experiment.
I filled a glass almost to the top with water, then added icecubes till the water came to the top of the glass.
Then I waited foe the ice to melt.
The water level remained the same and the glass never overflowed.
Eggxactly!
It’s curious that the biggest proponents of this crap build mega mansions ON THE BEACH!!
I ran the “sea rise” calculations myself, to see what complex model they used.
If you take the area of the ice cap times its mean thickness, you get an approximation of ice volume. Then you simply see what the volume of water would be, if it melted (a simple density change), and you get a number crudely approximating the water volume. Then add that volume evenly to the volume of existing ocean, and you get the “sea rise” number everyone tosses around. This is not a complex model, it’s back-of-the-envelope hand calculator stuff, with a few numbers from Wiki thrown in.
I did not consider density changes as a function of ice depth, I also assumed the ice is isotropic with no internal structure, and did not account for salinity or gravity. But I got the same “sea rise” number, so I probably got the “model” correct.
When scientists suddenly discover that the problem is more complex than the scare numbers the greens toss around, I am not surprised!
You should apply for grant monies.
I am intrigued by your ideas, I would like to subscribe to your newsletter...
If the ice cap melts, how much of it will end up in the oceans an how much will evaporate into the atmosphere as water vapor? If the earth and atmosphere is warmer, the air can hold more water vapor, no?
Thanks, but if you are logged in, you already subscribe to my newsletter!
Way back when, when Science and Nature were running articles about anthropogenic carbon dioxide, I wrote them a letter in which I took the global increase in CO2 from two papers, converted that to a mass of CO2, then took a paper on anthro produced CO2, and integrated the curve to get the anthro mass increase, and pointed out that the apparent global CO2 increase was a factor of ten bigger than the human-produced amount. This really was merely putting the various reported numbers in the same units system, nothing complex.
They never published the letter, either magazine, but it was after that that the greens started looking for cow farts and termite breath to make up the gap. By now, the numbers all agree, almost ALL global CO2 is accounted for by human activity!
This is I think why the public screwels de-emphasize math and science, it’s too easy to refute the claims of the greens.
Kowumbonga!!! Will the shullbit never end????
Hmmm.. sounds like global warming as really done it now, this says the earth is the one melting the ice sheets and not humans. Who’da thunk it????
“Deeply buried ice may melt because overlying layers insulate the base, hemming in heat created there by friction, or radiating naturally from underlying rock,” Columbia University said in a statement along with the study. “When the ice melts, refreezing may take place in multiple ways ... If it collects along mountain ridges and heads of valleys, where the ice is thinner, low temperatures penetrating from the surface may refreeze it. In other cases, water gets squeezed up valley walls, and changes pressure rapidly.
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