In Sign of Warming, 1,600 Years of Ice in Andes Melted in 25 Years

Here's another recent study on the melting of the glaciers in the Andes.

Andean glaciers melting at "unprecedented" rates: study
Reuters
Jan 24, 2013
(excerpts)
Climate change has shrunk Andean glaciers between 30 and 50 percent since the 1970s and could melt many of them away altogether in coming years, according to a study published on Tuesday in the journal The Cryosphere. Andean glaciers, a vital source of fresh water for tens of millions of South Americans, are retreating at their fastest rates in more than 300 years, according to the most comprehensive review of Andean ice loss so far. The study included data on about half of all Andean glaciers in South America, and blamed the ice loss on an average temperature spike of 0.7 degree Celsius (1.26 degrees Fahrenheit) over the past 70 years.

"Glacier retreat in the tropical Andes over the last three decades is unprecedented", said Antoine Rabatel, the lead author of the study and a scientist with the Laboratory for Glaciology and Environmental Geophysics in Grenoble, France. The researchers also warned that future warming could totally wipe out the smaller glaciers found at lower altitudes that store and release fresh water for downstream communities. "This is a serious concern because a large proportion of the population lives in arid regions to the west of the Andes", said Rabatel. The Chacaltaya glacier in the Bolivian Andes, once a ski resort, has already disappeared completely.

©2013 Thomson Reuters. All rights reserved.

(In accordance with Title 17 U.S.C. Section 107, this material is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes.)

 

Cooling trend came to a halt in much of the world near the end of the 19th century...

Scientists Reconstruct 2,000 Years of Temperature Change
April 22, 2013 WASHINGTON — A team of 78 researchers from around the world published a study on Monday detailing what they call the most comprehensive reconstruction of temperature changes on every continent for the last two millennia.

 

Seems frightening at first but not sure how just finding very old plant remains automatically means they haven't been smaller since they were trapped in the ice. Glaciers expand out, and anything trapped near the center say 6000 years ago would eventually be pushed out the ends.. At least that's how I have been told they expand outwards, and upwards.I remember studying their movement during the ice ages creates great gouges in the earth, making the great lakes for one thing. All that expansion, I'm sure there were some odd remnants left behind that was completely out of place back then.

 

In other words, you don't understand the science but you don't want to believe it. Typical denier cult attitude.

 

LOL, I just gave you the truth of how glaciers expand and your response to claim I don't understand the science... Which sounds more scientific to you, a realistic attitude about how glaciers grow and expand, or taking an alarmist claim for fact based on nothing more than "the ice melted and left this here, that means it's smaller than it was then."

Come on man, you know it was a silly assumption they tried to peddle here, that's why you're so mad. Don't blame me because their claim was presumptuous..

 

Well, it is very obvious that you don't understand the science. Let's look at what you said.

"Seems frightening at first but not sure how just finding very old plant remains automatically means they haven't been smaller since they were trapped in the ice. Glaciers expand out, and anything trapped near the center say 6000 years ago would eventually be pushed out the ends.. At least that's how I have been told they expand outwards, and upwards."

LOL. You're "not sure how" the science works, but you're sure that some poorly understood hearsay, "how [you] have been told", qualifies you to critique peer reviewed scientific techniques that you can't really comprehend.

The actual truth about how glaciers grow is that when it is cold enough all year in places where there is some precipitation, over time unmelted snowfall accumulates and compacts into ice and starts moving outward and downward under the pressure of its own weight.

Plants that got covered in ice and frozen a little over six thousand years ago were recently were uncovered by the retreating ice for the first time in all of those years, which indicates that the ice hasn't previously retreated as far as it has now in the last six thousand years.

From the OP:
The evidence comes from a remarkable find at the margins of the Quelccaya ice cap in Peru, the world’s largest tropical ice sheet. Rapid melting there in the modern era is uncovering plants that were locked in a deep freeze when the glacier advanced many thousands of years ago. Dating of those plants, using a radioactive form of carbon in the plant tissues that decays at a known rate, has given scientists an unusually precise method of determining the history of the ice sheet’s margins.

Several years ago, the team reported on plants that had been exposed near a meltwater lake. Chemical analysis showed them to be about 4,700 years old, proving that the ice cap had reached its smallest extent in nearly five millenniums. In the new research, a thousand feet of additional melting has exposed plants that laboratory analysis shows to be about 6,300 years old. The simplest interpretation, Dr. Thompson said, is that ice that accumulated over approximately 1,600 years melted back in no more than 25 years. “If any time in the last 6,000 years these plants had been exposed for any five-year period, they would have decayed”, Dr. Thompson said. “That tells us the ice cap had to be there 6,000 years ago”.

Quelccaya Ice Cap
From Wikipedia, the free encyclopedia
Type Mountain glacier/Icecap
Location Peru
Status Retreating
The Quelccaya Ice Cap is the largest glaciated area in the tropics. Located in the Cordillera Oriental section of the Andes mountains of Peru, the ice cap is at an average altitude of 5,470 meters (18,600 ft) and spans an area of 44 square kilometers (17 mi2). As with the majority of the Earth's glaciers, the Quelccaya Ice cap has retreated significantly since it was first studied. Since 1978 the icecap has lost approximately 20% of its area,[1] and the rate of retreat is increasing.

Comparing pictures taken in 1963 and 1978, an annual retreat rate of 4.7 meters (15.4 ft) was estimated. In the first few years of the 21st century, the annual retreat was measured to be as much as 205 meters (672 ft), more than 40 times as fast.[2] The major outlet glacier from the Quelccaya Ice Cap, the Qori Kalis Glacier, has also retreated significantly since 1963.

Lonnie Thompson and his research team have drilled ice cores from Quelccaya that date back almost 2,000 years and have used them to study changes in atmospheric conditions over this period. In these samples, the oxygen isotope ratio, oxygen-18 to oxygen-16, has risen abruptly in the last 50 years, an indicator of regional warming. As the ice cap is retreating, it is exposing almost perfectly preserved, unfossilized plant specimens that have been dated to 5,200 years before present, indicating that it has been more than 50 centuries since the ice cap was smaller than it is today.[3]

LOLOLOLOL....."what sounds more scientific" to me is the actual scientific research done by actual scientists who know what they're doing, not the ignorant musings of a politically motivated and very clueless anti-science denier.

 

Have you read the original paper in the journal in which appeared?

 

Have you? I wasn't aware of a link to that paper, if you have seen this link please post it...

What I DID see was a link to a NY Times alarmist article...

I explained why I disagree with the hypothesis and claims of the article, and did so using actual logic regarding the way glaciers grow and shrink, flow and stop. They don't grow as the article leads people to believe. They grow and shrink in much the way I explained. Showing that claims regarding the findings of ancient plant material around the edges proving they are smaller now than they were 6000 years ago, is speculative at best and certainly not a proof of anything other than the fact the glacier has moved over that time..

Again, glaciers do not grow and shrink along a defined edge or parameter. They grow up and out and not uniformly, things can be pushed out to the edges from deep under the ice and that's not specualtion but know and proven fact...

http://nsidc.org/cryosphere/glaciers/life-glacier.html

From the NSIDC website on the matter...Again, they grow and expand leaving matter in their wake. Dating the matter found does not mean the glacier wasn't smaller or bigger before, it simply means the glaciers moved the matter...

 

If you did not read the actual paper, how do you know the scientists doing the research did not take into account the way glaciers grow?

 

Simple the article stated how they came to the conclusion, I don't think the NY times would bother lying about it do you?

If you want to debate the articles accuracy or validity, please do so. I am debating what I have been shown and given here.The article was the point of the OP, the NY times is responsible for their end.

Either way, the way they described their findings and claims, do not match the way Glaciers shrink and expand. The fact is the plant material could have come from anywhere that glacier has covered the last 6000 years. To claim it shows the ice is smaller now than before based on what you find by it's edges is speculative at best, and scientifically premature. It's not new scientists need grant money and global warming is the cash cow for glacier research. Wouldn't be the first premature claim of proof to some thing..

 

NY Times article does not explain methods used to come to a conclusion; it only gives the conclusion of the study. Only way to credibly criticize the study's conclusions is to read the original study, understand the methods used and how they came to the conclusion. Anything other criticism is nothing but the personal opinion of an anonymous poster on an internet forum. Nothing personal, but I'll accept conclusions of the abstract of the paper over someone who's never even read the abstract.

 

LOL,dude did you read the article? They talked about the findings not a whole lot of grey area involved.They made the claim, NY times reported it.

How exactly do you think they can actually prove the plant matter didn't come from under neath the glacier ice? Tell ya what, you find the link to the paper in that article, post it here and I'll read it.. Until they can prove beyond a reasonable doubt the matter was not pushed out from the bottom of the glacier, and it in fact DOES prove the glacier is smaller now, I will stand by my assertions..

 

You want to read the paper, go visit your local library' I'm sure they have a copy of Science. I know I will next time I have a chance.
Without knowing the methodology used, you cannot criticize the paper. How much do you think plant matter can move inside a glacier? Five feet a year? Twenty feet a year? Give me a value. How much plant matter was dated? one plant? twenty plants? All this is relevent to the accuracy of the conclusions? For how much movement of plant matter did Dr. Thompson allow? What deviations did he use? You know none of this because a newspaper article does not attempt to address these questions.
Again, without knowing the methodology, you do not have a clue on how accurate the study's conclusion are. You cannot make accurate assertions without knowing all the facts. And you do not have all the facts.

 

And you cannot proclaim it correct either... Works both ways.. The only attempts at accurate assertions come from the article. I explained how glaciers move and how material can be moved by them,and how it is misleading to claim old plant material found in such a manner shows anything about the current size of it..

 

No! It does not work both ways. You made a claim that the study and methods are wrong. You need to back that claim with facts; something you are unable to do because you have not read the paper.
And you're just going to ignore the rest of my previous post; not going to answer any questions? Why am I not surprised?

 

I commented on the article because that was what he posted and what he commented on, and what the debate was about.. You seem to think It's my job to support your claim against my side of the debate.. No it doesn't work that way... I explained how glaciers move and grow and shrink and backed it up with a viable and expert source...The NSIDC, glaciers, ice,snow it's their job man... I think they know how glaciers grow and shrink...The link again just as it was linked, cited and quoted in my previous post...

http://nsidc.org/cryosphere/glaciers/life-glacier.html

Notice the underlined and bolded and underlined parts..They confirm what I have said all along... Again...

Now the abstract you linked to does NOT directly address any such claims regarding methodology used to determine how the plant material may have been there. All they say is the fact it is there because the ice melted and it could mean the ice is therefore smaller than it was... It isn't a fact, it's a theory,one that I call dubious because the NSIDC explains how glaciers grow, shrink and expand, and say point blank that this causes deposits that can move with the glacier in a number of ways,or become trapped in the ice itself.. I quote them again.."Throughout advance and retreat, glacial debris sediment known as till is jostled in all directions. Till is thrust forward with the glacier, brushed aside as the glacier pushes past less mobile objects, such as a mountainside, or drawn along on the glacier's journey."

Now I agree with the NSIDC, and from any basic science class you should have learnedthe basics of how glaciers grow and expand as well as shrink.It's not a new concept it's been around a long time.. The paper is speculative in my opinion, and here once again is my evidence for my claim...

Now,your evidence so far has been to cite the abstract of the paper in question after asking me to do it first.... If all you have is the word of the scientists involved in the paper in question, you don't have any evidence. So please if you disagree it's your right to, but don't assume I didn't back up my claim, just because you failed to see it or read the post fully..I say it's a speculative claim they made, and you say it isn't. I have the explanation of how glaciers grow, expand and shrink from the NSIDC who are experts in the field. you have an abstract from the paper in question..

I'll take the expert source outside of the study, over the ones doing the study...