From the University of Vermont
Science: There’s something ancient in the icebox
Researchers find 3-million-year-old landscape beneath Greenland Ice Sheet
Glaciers are commonly thought to work like a belt sander. As they move over the land they scrape off everything—vegetation, soil, and even the top layer of bedrock. So scientists were greatly surprised to discover an ancient tundra landscape preserved under the Greenland Ice Sheet, below two miles of ice.
“We found organic soil that has been frozen to the bottom of the ice sheet for 2.7 million years,” said University of Vermont geologist Paul Bierman—providing strong evidence that the Greenland Ice Sheet has persisted much longer than previously known, enduring through many past periods of global warming.
He led an international team of scientists that reported their discovery on April 17 in the journal Science.
Greenland is a place of great interest to scientists and policymakers since the future stability of its huge ice sheet—the size of Alaska, and second only to Antarctica—will have a fundamental influence on how fast and high global sea levels rise from human-caused climate change.
“The ancient soil under the Greenland ice sheet helps to unravel an important mystery surrounding climate change,” said Dylan Rood a co-author on the new study from the Scottish Universities Environmental Research Centre and the University of California, Santa Barbara, “how did big ice sheets melt and grow in response to changes in temperature?”
The new discovery indicates that even during the warmest periods since the ice sheet formed, the center of Greenland remained stable; “it’s likely that it did not fully melt at any time,” Vermont’s Bierman said. This allowed a tundra landscape to be locked away, unmodified, under ice through millions of years of global warming and cooling.
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  IMAGE: This is a piece of the GISP2 ice core showing silt and sand embedded in ice. Soon after this picture was taken, the ice was crushed in the University…Click here for more information. |
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“The traditional knowledge about glaciers is that they are very powerful agents of erosion and can effectively strip a landscape clean,” said study co-author Lee Corbett, a UVM graduate student who prepared the silty ice samples for analysis. Instead, “we demonstrate that the Greenland Ice Sheet is not acting as an agent of erosion; in fact, at it’s center, it has performed incredibly little erosion since its inception almost three million years ago.”
Rather than scraping and sculpting the landscape, the ice sheet has been frozen to the ground, “a refrigerator that’s preserved this antique landscape,” Bierman said.
The scientists tested seventeen “dirty ice” samples from the bottommost forty feet of the 10,019-foot GISP2 ice core extracted from Summit, Greenland, in 1993. “Over twenty years, only a few people had looked hard at the sediments from the bottom of the core,” Bierman said. From this sediment, he and a team at the University of Vermont’s Cosmogenic Nuclide Laboratory extracted a rare form of the element beryllium, an isotope called beryllium-10. Formed by cosmic rays, it falls from the sky and sticks to rock and soil. The longer soil is exposed at Earth’s surface, the more beryllium-10 it accumulates. Measuring how much is in soil or a rock gives geologists a kind of exposure clock.
The researchers expected to only find soil eroded from glacier-scoured bedrock in the sediment at the bottom of the ice core. “So we thought we were going looking for a needle in haystack,” Bierman said. They planned to work diligently to find vanishingly small amounts of the beryllium—since the landscape under the ice sheet would have not been exposed to the sky. “It turned out that we found an elephant in a haystack,” he said; the silt had very high concentrations of the isotope when the team measured it on a particle accelerator at Lawrence Livermore National Laboratory.
“On a global basis, we only find these sorts of beryllium concentrations in soils that have developed over hundreds of thousands to millions of years,” said Joseph Graly, who analyzed the beryllium data while at the University of Vermont.
The new research, supported by funding from the National Science Foundation, shows that “the soil had been stable and exposed at the surface for somewhere between 200,000 and one million years before being covered by ice,” notes Ben Crosby, a member of the research team from Idaho State University.
To help interpret these unexpected findings, the team also measured nitrogen and carbon that could have been left by plant material in the core sample. “The fact that measurable amounts of organic material were found in the silty ice indicates that soil must have been present under the ice,” said co-author Andrea Lini at the University of Vermont—and its composition suggests that the pre-glacial landscape may have been a partially forested tundra.
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 IMAGE: Scientists were greatly surprised to discover an ancient tundra landscape preserved under the center of the Greenland Ice Sheet, below two miles of ice. “We found organic soil that has…Click here for more information. |
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“Greenland really was green! However, it was millions of years ago,” said Rood, “Greenland looked like the green Alaskan tundra, before it was covered by the second largest body of ice on Earth.” To confirm their findings about this ancient landscape, the researchers also measured beryllium levels in a modern permafrost tundra soil on the North Slope of Alaska. “The values were very similar,” said Bierman, “which made us more confident that what we found under Greenland was tundra soil.”
Many geologists are seeking a long-term view of the history of the Greenland Ice Sheet, including how it moves and has shaped the landscape beneath it—with an eye toward better understanding its future behavior. It’s 656,000 square miles of ice, containing enough water, if fully melted, to raise global sea levels twenty-three feet—”yet we have very little information about what is happening at the bed with regards to erosion and landscape formation,” said Corbett.
What is clear, however, from an abundance of worldwide indicators, is that global temperatures are on a path to be “far warmer than the warmest interglacials in millions of years,” said Bierman. “There is a 2.7-million-year-old soil sitting under Greenland. The ice sheet on top of it has not disappeared in the time in which humans became a species. But if we keep on our current trajectory, the ice sheet will not survive. And once you clear it off, it’s really hard to put it back on.”
You know, it’s not nice to slam the global warming ad at the end of every study. That’s the requirement for getting the grant these days, and a few words of transparent bullstucco is the price researchers must pay for the basic science “above the fold”. It’s unfortunate, but research doesn’t pay for itself and will always be at the mercy of whoever has the gold making the rules.
The last paragraph of the quoted article is such retarded gibberish that its an embarrassment to the human race.
In his book – The Energy Nob-Crisis – Lindsey Williams recounts his time as chaplain to the oil companies in North Alaska that were involved in drilling for oil. He stated:
“There is an interesting point to mention in passing. Though the ground is frozen 1,900 feet down from the surface at Prudhoe Bay, everywhere the oil companies drilled around this area they discovered an ancient tropical forest It was in a frozen state, not in petrified state. It is between 1,100 and 1,700 feet down. There are palm trees, pine trees, and tropical foliage in great profusion. In fact, they found them lapped all over each other, just as though they had fallen in that position.
What great catastrophe caused this massive upheaval, and then led to such dramatic changes to the climate? We stress again that everything is frozen – not petrified – and that the whole area has never once thawed since that great catastrophe took place.”
He states:
“It is also interesting to remember that the great Arctic explorer, Admiral Byrd, reported seeing tropical growth in near Arctic regions.”
He adds:
“The finding of underground tropical growth is not hearsay, for I have personally watched these palm trees and other types of tropical plants being brought up to the surface.”
What he then goes on to reveal in the particular chapter is truly mind blowing.
The point I make is that evidence is readily available to scientists, should they bother to seek it, that the Arctic region was once tropical until a major climatic event occurred to change that.
While I applaud this kind of “Let’s actually see if our surmises are correct” science, in this case I submit that the interpretation of this evidence may not be warranted. I argue that it is NOT clear from what is known if the ice over GISP2’s location moved or not.
From above: “Instead, ‘we demonstrate that the Greenland Ice Sheet is not acting as an agent of erosion; in fact, at it’s center, it has performed incredibly little erosion since its inception almost three million years ago.’”
According to The Summit core was taken at 72° 36′ N, 38° 30′ W. Its name is quite descriptive. This is the top of the ice sheet in Greenland. That means that the amount of ice movement there is minimal or even possibly non-existent. A few mouse movements on Google Earth at that are will reveal a generally flat summit area for quite a distance around the core location. What does that mean?
Ice does not flow over flat ground; people tend to think that all ice of any great thickness flows downhill. Yes, that is true – IF the underlying ground allows it – if there IS a downhill. We are all familiar with the fact that water flows downhill – unless what? If there is a berm to contain it (forming a basin), water does what instead? It forms a pond or a lake. Or in really small cases, water forms puddles or bogs. As is common in tundras. So, if the land is flat or has a basin, then the ice will stay put and not move. Glaciers flow for one of two reasons: The ground has a slope to it, and/or the ice above it pushes it – both are due to gravity. So GLACIERS scour nthe ground inderneath. It is altogether unproven that ice at the top of Greenland or Antarctica itself moves. That ia an assumption, but should not be accepted as rtue in all cases. Sometimes yes. Sometimes no. Which is the GISP2 location? Do we know?
From the description they have found tundra-like soil at that location. I submit this photo as an example of tundra land: http://en.wikipedia.org/wiki/File:Tundra_in_Siberia.jpg Other tundra photos are available. Go look at them. Some are on land which is flat, some are not so flat. So ice over tundras may flow downhill or they may not – depending if a “downhill” exists or not.
With only one geographic data point in the GISP2 core, it is likely that it cannot be established whether the tundra below is flat or had some downhill to it – unless precise local maps exist of the terrain underneath. If no downhill exists, then there is little to no reason for the ice above it to have ever moved.
Thus the conclusion about ice scouring is premature. IMHO.
If we keep it up, the ice sheet won’t survive, despite dating back 3 million years? They’re really getting desperate for cata-scenarios, now. What horse pucky.
@Patrick Guinness April 17, 2014 at 6:28 pm – If you are still around, you might be interested in the 1955 paper “HAS THE AMOUNT OF CARBON DIOXIDE IN THE ATMOSPHERE CHANGED SIGNIFICANTLY SINCE THE BEGINNING OF THE TWENTIETH CENTURY?” by Giles Slocum (U. S. Weather Bureau, Washington, D. C.) questioning Callendar’s selection of data and Callendar’s conclusions.
See http://www.pensee-unique.eu/001_mwr-083-10-0225.pdf
In it Slocum pointed out this:
“Callendar’s and Buch’s averages appear, as presented in figure 1, to show an increase in COz from the late nineteenth century to the beginning of the middle third of the twentieth.
Their comparisons are, however, based on a narrow selection of values from a much larger body of data, scattered through the scientific literature of the past century. It may be granted that the data they used are probably quite accurate averages for the time, place, meteorological conditions, etc., of observation. The question remains, however, are all the measurements which they did not use, inaccurate?
Buch who followed Callendar, accepts without challenge Callendar’s selection of data, and merely adds his own observational material. Hutchinson [19] bases his statement that CO, has increased on Callendar’s results, although he limits his corroboration to the case of the air in the North Temperate zone. Brown and Dingle alone offer any new evidence on the amount of C02 in the atmosphere, and their evidence, if it be not negative, is not necessarily confirmatory.
Since Callendar, by basing his hypotheses on statistical data, has tacitly invoked the laws of statistical evidence, it is fitting to examine the validity of his procedure, that of using only the data he believed to be of the best quality available, rejecting the rest. The mathematics of statistics, and the experience of
statisticians both indicate, as a general principle, that arbitrary rejection of data, without specific knowledge of their unreliability or unapplicability, is questionable.”
Also this:
“Reference to the three charts in figure 3 does not reveal any significant trend in COa content, such as is so clearly shown in figure 1. Indeed, after excluding values which the observers themselves have designated as non-representative, but not any of the others, then the mean value for the nineteenth century is 335, and for the 1st third of the twentieth century 334 parts per million.”…
And this:
“The means that Callendar rejected from the nineteenth century records are, in the main, indicative of higher values than those he accepted. He points out that the accuracy of observations improved as time went on, and that early techniques tended to give too high values. Statistically speaking, the data in table 3 could well be drawn from a population having these properties. The three values for the twentieth century, however, which Callendar rejected average lower than those he accepted. This does not demonstrate that his choice was bad, but the fact that he considers so many nineteenth century values to be overestimates and two twentieth century values to be underestimates raises a question about his method of selection.”
Callendar making older data values lower and recent data values higher – by the way he rejected data – is similar to the climate scientists who keep adjusting older values down, and by doing so appearing to give a steeper and more sinister slope to the increases in global temps. Rejecting inconvenient data we now call cherry picking.
I would also point out that in Slocum’s presentation of Callendar’s data, neither of them happened to note that Callendar’s data was NOT for the entire 19th century (the great majority was after 1866). In fact, Callendar listed two collections of data from the first half of the 19th century (probably the first ever data studies on CO2) – and BOTH of those had values over 400! These were higher than even NOW.
to 23skiddo, who said:
“Are you in fact talking about sea level change? There’s a great deal more than 23 vertical feet of ice on Greenland. The maximum thickness is about 4,000 meters IIRC.”
Yes, if all of Greenland’s ice were to melt, it would add only 23 feet to sea level. The article says this:
” It’s 656,000 square miles of ice, containing enough water, if fully melted, to raise global sea levels twenty-three feet”
You can google if you wish, but you will get the same answer. Certainly, the ice goes far higher vertically, as ice on Greenland, but it isn’t spread out over all the oceans, as it would be if it melted. That is why ice that goes to 10,000 feet, if melted, would only add the 23 feet to sea level rise.
Interesting time stamp versus the closure of the Isthmus of Panama and onset of the Pleistocene. If none of the interglacials re-exposed those strata, then we can safely say we really are still, technically speaking, still in a Pleistocene regime, and our notion of The Holocene is sort of bogus.