'Benchmark glaciers' shrinking at faster rate, study finds
August 7, 2009 By Les Blumenthal and Erika BolstadClimate change is shrinking three of the nation's most studied glaciers at an accelerated rate, and government scientists say that finding bolsters global concerns about rising sea levels and the availability of fresh drinking water.
Known as "benchmark glaciers," the South Cascade Glacier in Washington state, the Wolverine Glacier on Alaska's Kenai Peninsula and the Gulkana Glacier in interior Alaska all have shown a "rapid and sustained" retreat, according to a report by the U.S. Geological Survey that was released Thursday.
"They are living on the edge," Ed Josberger, a USGS scientist based in Tacoma, Wash., said of the three glaciers. "We've crossed a threshold, and these glaciers along with those globally are shrinking."
For years, scientists have reported that glaciers around the world are melting, but the study offers some of the most definitive evidence to date. Because the three glaciers are in different climates and elevations, they can be used to help understand thousands of other North American glaciers.
At the beginning of the 20th century, when glaciers were at their last peak in terms of size, the mass, or volume, of the remote South Cascade Glacier was estimated to be half a cubic kilometer, or about 654 million cubic yards. By 1958, it had shrunk to half that size. The latest measurement, in 2004, found that it had shrunk by half yet again.
"We are getting warmer, and glaciers are shrinking," Josberger said.
With some exceptions caused by unique or unusual local conditions -- the glaciers on California's Mount Shasta, for example -- more than 99 percent of the country's thousands of glaciers are shrinking, said Bruce Molnia, another USGS scientist.
USGS scientists have been taking measurements and detailed pictures of the three glaciers in the study since 1957, including using ice-penetrating radar to map the bedrock beneath them. The studies, begun as part of the International Geophysical Year, were part of a Cold War-era interest in polar science spurred by the threat of war with another polar nation, the Soviet Union.
The result is a half-century's worth of data to use for modeling future changes, said Shad O'Neel, one of the USGS scientists based in Anchorage, Alaska, who worked on the study.
"These three glaciers have been losing mass since they've been studied, and that mass loss has gotten more rapid in the past 15 years," O'Neel said. "The most important thing about having a long record like this is that we can use these records to verify and validate models out into the future."
Although their data show a marked retreat in the sizes of the glaciers, changes to Alaska's many glaciers are also visible to the naked eye, O'Neel said. Gulkana Glacier is "markedly different than it was in the late 1980s," he said.
Worldwide, most glaciers are losing mass, and some are disappearing. Glacier National Park's namesake glaciers in Montana decreased from 150 to 26 over the past 99 years, and if current warming trends continue, scientists predict, they'll disappear entirely by 2030. Scientists also have predicted that the famed snows of Africa's Mount Kilimanjaro could retreat by 2015.
Scientists at the USGS's Northern Rocky Mountain Science Center, who study the glaciers in Montana, point out that a drop in runoff means changes in water temperature for the creatures in the downstream ecosystem: insects, fish and the animals that eat them.
It also means less available drinking water, O'Neel said, pointing out that Anchorage's drinking water is derived from runoff from Eklutna Glacier. There's little threat to Anchorage's water supply, but Bolivia's Chacaltaya Glacier disappeared this year, earlier than predicted. Its disappearance worries scientists that other glaciers in the region could be melting faster than expected, potentially threatening water supplies for millions of people in South America.
The long-term study is "exactly the kind of science we need to invest in to measure and mitigate the dangerous impacts of climate change," Interior Secretary Ken Salazar said.
ON THE WEB
The USGS study: http://pubs.usgs.gov/fs/2009/3046/
Glacier National Park: http://www.nps.gov/glac
Northern Rocky Mountain Science Center: http://www.nrmsc.usgs.gov/research/global.htm
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Visit the McClatchy Washington Bureau on the World Wide Web at http://www.mcclatchydc.com
Oct 06, 2008 |
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http://www.physor...353.html
Loss from the South Cascade glacier has in fact been accelerating. But the Gulkana and Wolverine glaciers, while still losing mass, show absolutely no recent increase in their rate of loss. Since the early 1990s, they have been losing mass at about the same rate.
This is advocacy disguised as science. Don't believe me? Do what Les and Erika should have done ... look at the official records at http://ak.water.u...ance.txt
They calculated the previous data up to make the loss for this time period more dramatic.
or down to make it less dramatic
You'd be terrible in the news business.
(Read Krimmel's paper, it was adjusted up significantly).
Your right, I would be terrible in the news business. I like to think that I try to be unbiased.
I suspect that the data was reanalysed due to some systematic error and that the result was to make it more accurate. I can't be sure though as I haven't been able to find the paper, can you post a link?
http://www.curac....artz.pdf
http://www.curac....artz.pdf
I can read enough German to get the gist of "minimal-invasiver endoskopischer Operationsmethoden"
This paper has nothing to do with glaciers as the diagrams at the end make abundantly clear, and was not written by R.M.Krimmel although it does contain a reference to M Krimmels paper
"M Krimmel, J Hoffmann, D Gulicher et al. (Krimmel 2000):
Bedeutung der Videoendoskopie f%uFFFDr die operative Versorgung von Jochbeinfrakturen. 38. Jahrestagung der Deutschen Gesellschaft f%uFFFDr Plastische und Wiederherstellungschirurgie, 2000."
This has nothing to do with glaciers either.
The paper relating to the glacier data is
"Krimmel, R.M., 2000, Water, ice, and meteorological measurements at South Cascade Glacier, Washington, 1986 - 1991 balance years: U.S. Geological Survey Water-Resources Investigations Report 00-4006, 77p."
I would be grateful to anybody who could supply a link to this paper, as I've been unable to find one anywhere, and I think it only fair to give it a reading before commenting on the author's honesty
This is an article from U.S. Geological Survey, which is not present on their site, meaning you'll probably have to find it at your local library or order it from the USGS.
http://www.wester...ngs/1974 WEB/KrimmelSouthCascadeGlacierRunoff1974.pdf
Then
and then
and then finally
It would appear to me that you have never read this paper (not even in German). Therefore you are in no position to comment on other people's honesty.
If you take a single mistake as wrongdoing, then you'll find yourself very alone. I read many hundreds of scientific papers each month. To mistake Krimmel 2000 and Krimmel 2000 was not intentioned. If you take it as so, well, sorry is the best I can offer.
Look at the data, five of the six data points between 1986-91 show a decrease in the rate of loss and the last point shows a net gain. This doesn't look "more dramatic" to me.
This is not the first time you have posted irrelevant or misleading links.
http://www.physor...625.html
The authors name at the top of page one is Bartz Dirk, Krimmel is not even one of the co-authors, and in fact the name only appears onceat the bottom of the references on page two.
If you read German and recognised the name and familiar text format why didn't you see the title, after all it's in large bold type right under the list of authors.
I'm quite happy to read the German paper you claim to have read, go on prove me wrong, post a link.
And I've been looking for a link. The USGS doesn't have the paper on their site any longer.
You no nothing of the initial measurements.
Hypocrite
Post in hast regret at leisure, that should have read
"You know nothing of the initial measurements."
Game?
You accuse somebody of falsifying data and think it's a game?
Prove it or apologise