Antarctica May Contain "Oasis of Life"

National Geographic News ^ | Thursday, December 27, 2007 | Christine Dell'Amore

[SunkenCiv]

Researchers have uncovered a complex subglacial system miles under the ice where rivers larger than the Amazon link a series of "lake districts," which may teem with mineral-hungry microbes. This watery environment may be more than one-and-a-half times the size of the United States, scientists say, which would make it the world's largest wetland... Studinger's research focuses on "recovery lakes," part of a a series of cascading lakes found earlier this year under the ice sheet. The lakes... ebb and flow as they empty into the polar sea. They stay fluid because the ice sheet above acts like a gigantic down blanket, trapping heat rising from Earth's interior. About 145 lakes have been found, under ice up to 2.5 miles (4 kilometers) thick... Outbursts from subglacial lakes, for example, may have a lot to do with how the continents are shaped and reshaped. The lakes may also hold an untapped wealth of climate records that could improve our understanding of how life evolved, he added. Some of these mysteries might be cracked within months, when Russian scientists drill down 2.3 miles (3.8 kilometers) to reach Lake Vostok. The giant lake, 2.5 miles (4 kilometers) beneath eastern Antarctica, was found in 1996 using satellite imagery and specialized radar technology.

[Fred Nerks]

Although the dates aren't exactly spelled out, presumably they have a fairly good idea how far back in time the ice cores go, so where's the beef???

Whilst searching for further information on ice-core dating, I ran across this:

>A 1000 year ice core climate record from the Guliya Ice Cap, China and its relationship to global climate variability. Annals of Glaciology, 21, 175-181.ABSTRACT LINK.

(3) the analyses of the upper 100 meters of the 308.6 meter core which provide a 1000-year history, including the Little Ice Age, which is compared with Chinese historical records. Extended periods of positive accumulation on Guliya are closely contemporaneous with dry periods in eastern China. A trans-Pacific teleconnection is suggested by the strong temporal coherence between extended wet and dry phases on Guliya and on the Quelccaya ice cap, Peru. --------------

So, if a 100 meters provide a 1,000 year history, may we assume the ice in this region is approx three thousand YO?

See, that wasn't so difficult was it, LOL! This was written in 1995. Before globull warming and albore...and just maybe there wasn't a creationist or a uniformitarian anywhere in sight...?

[SunkenCiv]

:’) I’ve got trays in my freezer that old. ;’)

[SunkenCiv]

That was a nice snip, bears resnippin':

the layers in ice cores are not generally visible in the ice. They only become apparent when the core is analysed for a chemical signal that varies with the seasons, which most signals do, to some extent. In fact the clearest dating is obtained when several seasonal signals are examined and compared...

[SunkenCiv]

The presence of plant material under the ice indicates that the Greenland ice sheet formed relatively fast, as a slowly growing glacier would have flushed or pushed these light particles away."...

Gosh, that can't be right... ;') ;') ;'D ;'D

[Fred Nerks]

A New Alpine Melt Theory.LINK.

The Alpine glaciers are shrinking, that much we know. But new research suggests that in the time of the Roman Empire, they were smaller than today. And 7,000 years ago they probably weren't around at all...

... He and a colleague are standing in front of the Tschierva Glacier in Engadin, Switzerland at 2,200 meters (7,217 feet). "A few thousand years ago, there were no glaciers here at all," he says. "Back then we would have been standing in the middle of a forest." He digs into the ground with his mountain boot until something dark appears: an old tree trunk, covered in ice, polished by water and almost black with humidity. "And here is the proof," says Joerin...

[ForGod'sSake]

(And if so, any carbon dating result from the material brought up from beneath the ice in Greenland would really mess up the dates!)

To be sure, but still in all, it might be instructive to learn why there was no attempt(apparently) to date the material. For all I know, given the circumstances, it may not be possible, but inquiring minds and all...

Just did a little looking around and found THIS:

---

Oldest Known DNA Found in Greenland Ice Core

Mason Inman
for National Geographic News

July 5, 2007

The oldest known strands of DNA have been recovered from frozen mud taken from the base of Greenland's ice sheet, according to a new study.

The discovery could rewrite what was thought about Greenland's ecological past—and could alter current predictions about how global warming will affect the island's ice.

Today most of the Danish-owned island is covered with an ice sheet up to two miles (three kilometers) thick.

But the newfound DNA—genetic material from pine trees, butterflies, and other organisms that lived as much as 800,000 years ago—tells a story of a much greener and vibrant past.

Hundreds of thousands of years ago southern Greenland had thriving forests similar to those in northern Canada today, says an international team of 30 scientists led by Eske Willerslev of the University of Copenhagen in Denmark.

(See a map of Canada showing its position relative to Greenland.)

The find surpasses the previous record for the oldest DNA, which came from mammoths and other animals frozen in Siberia about 300,000 to 400,000 years ago.

The study also implies that Greenland's ice sheet did not melt as much as computer models have predicted during a period 125,000 years ago, when Earth's sea level rose dramatically.

This raises the question of where the water actually came from.

The research is described in tomorrow's issue of the journal Science.

Core Findings

At a site in the center of southern Greenland, researchers drilled through the thick ice until they reached the bottom layer of frozen mud, similar to the permafrost now found across areas such as Siberia.

Using a variety of techniques, the researchers were able to put an approximate date on the frozen mud: between 450,000 and 800,000 years.

"I'm not super-surprised that DNA could last that long" in Greenland, Willerslev said. "It's pretty much ideal conditions for DNA preservation."

Today it's a frigid -4°F (-20°C) at the bottom of the ice sheet at this spot, about 300 miles (500 kilometers) north of the southern tip of the island (see a map of Greenland).

Researchers have known that Greenland had some trees in the past, since they've found fossilized trees more than two million years old on the north coast of the island.

But it has been difficult to tell what the island's full ecosystem was actually like.

"Ten percent of Earth's surface is covered with ice," Willerslev said. "We have little information about the ecosystems that were there before [these places froze over]."

By comparing the DNA they found to that of today's plants and insects, the team identified the flora and fauna that used to live in this part of Greenland.

They found a variety of trees, including spruce and pine, similar to those found in northern boreal forests across Canada and northern Eurasia.

They also found signs of a number of creatures such as beetles, spiders, and butterflies.

All this suggests that before the area froze over, it had an open forest that supported a diverse ecosystem.

Mystery Melt

While these DNA discoveries help answer questions about Greenland's past environment, they may have created a new mystery related to global warming.

Based on computer models, some researchers had thought that most of southern Greenland was ice-free about 125,000 years ago, during the last interglacial period—a gap in time between ice ages when Earth was warmer.

During this period, sea levels rose about 16 to 19 feet (5 to 6 meters).

Many researchers thought that much of this water came from the melting of the southern part of Greenland's ice sheet during this time.

Several studies have found that Greenland's ice sheet is melting today, so scientists are working to predict how much the melt might contribute to sea level rise if the world continues warming.

(Related news: "Greenland Melt May Swamp LA, Other Cities, Study Says" [April 8, 2004].)

But "then we started to date [the ice] and we found that it wasn't that young," Willerslev said.

If the island had been free of ice during the last interglacial, it would likely have supported plants and animals.

In that case, DNA from those creatures should have been found instead of the DNA from the much older forest.

The new discoveries suggest that southern Greenland has been ice-covered for at least four times longer than previously thought.

"We have firm data to state that there was ice in central and northern Greenland," said Valerie Masson-Delmotte of the Laboratory of Climate and Environmental Sciences in Saclay, France.

"The main surprise [of the new study] is the persistency of ice in southern Greenland," said Masson-Delmotte, who was not involved in the new study.

And if the region was still frozen during the last interglacial period, lead author Willerslev said, then some of that water "must have come from some melting of ice somewhere else."

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FWIW...

[Fred Nerks]

To be sure, but still in all, it might be instructive to learn why there was no attempt(apparently) to date the material. For all I know, given the circumstances, it may not be possible, but inquiring minds and all...

I cannot find any reference to this material (looked like a pine needle) having been dated. Nothing, silch. As for:Oldest Known DNA Found in Greenland Ice Core

I can't seem to get past the 'global warming' part, LOL! If I find a report without the spin and bias, I'll ping you.

[Fred Nerks]

Ancient Flora and Fauna. LINK.

At the DYE-3 drilling-site, the ice is ‘only’ two kilometres thick, and here the DNA-material was so well preserved that Eske Willerslev could extract genetic traces of a long list of plants and insects and thereby reconstruct ancient plant and animal life.

“This genetic material presents a biological environment, which is completely different to what we see today.” he says. “We have found grain, pine, yew and alder. These correspond to the landscapes we find in Eastern Canada and in the Swedish forests today. The trees provide a backdrop from which we can also ascertain the climate since each species has its own temperature requirements. The yew trees reveal that the temperature during the winter could not have been lower than minus 17 degrees Celsius, and the presence of other trees shows that summer temperatures were at least 10 degrees”.

And now we know why they need to prove it existed such a very long time ago...a more recent date would point to CATASTROPHE.

[Fred Nerks]

You may enjoy this:

LATELY TORTURED EARTH. LINK.

btw, how could trees and grass grow, and birds and butterflies live where it's dark four months of the year?

[Fred Nerks]

http://i7.photobucket.com/albums/y258/FredNerks/mapCanadaBasin-1.jpg

Interesting graphic

[ForGod'sSake]

I can't seem to get past the 'global warming' part...

Yeah, it galls me to have to wade through the genuflecting to the GW gods as well. That said, if ALL of Greenland has been covered with ice for as long as a million years, the Vikings, or whoever named the island, must have had a creative streak. Or maybe they had gotten too far down into their mead horns.

[Fred Nerks]

I’m beginning to think Greenland was a colony for thousands of years, the forests, the ‘grain’ and the insects, all the same as grew on the nearby (european)continent, suggests as much.

[ForGod'sSake]

btw, how could trees and grass grow, and birds and butterflies live where it's dark four months of the year?

By going dormant in the winter??? The birds and other critters would probably have to make other arrangements. Head south, or hibernate maybe???

[ForGod'sSake]

Entertaining link BTW.

[ninonitti]

7,000 years and that the area was once warmer than it is today.

So if it were warmer then it must have gotten cooler so that we could now be undergoing global warming after global cooling......just wondering

[ForGod'sSake]

Interesting graphic

What am I looking at here Fred, a pretty deep hole in an otherwise smooth the ocean floor? So, reckon how the hole got there???

[ForGod'sSake]

I’m beginning to think Greenland was a colony for thousands of years...

Maybe; maybe not, but it appears the scientific community is determined to prove it wasn't.

[Fred Nerks]

So, reckon how the hole got there???

try squeezing it together and see what happens!

[ForGod'sSake]

try squeezing it together and see what happens!

I guess the point being, the land masses were much closer together once upon a time??? It also looks to be near what would be the beginning of the Mid-Atlantic Ridge. In any case, the graphic itself also appears to be a an exaggerated depiction(for purposes of illustration?) of this:

Not nearly as exciting.

[Fred Nerks]

not nearly as exciting...

I agree with you, I can't remember now where I lifted that graphic from.

Perhaps it doesn't look as spectacular because the depth is missing.