Fast Ice: Redux – West Antarctica
Fast Ice: Redux – West Antarctica
I want to return to an old subject. Early on in this blog I wrote a series of blogs about melting ice on land. Here are the links to those blogs.
Fast Ice 1
The End of Ice
Warm Snow
These previous blogs talked about how glaciers and ice sheets that have their ends in the seas and at ice shelves have many interesting ways to melt. There is also the discussion of how in an atmosphere which is warming there is the possibility of their being more snow on the ice sheets in East Antarctia and Central Greenland. Hence, there is this idea of a balance, in this case the balance of mass of water in the ice sheets. There is melting and there is accumulation.
Figure 1: Figure and Caption Text from University of Texas (link): Schematic of the West Antarctic ice sheet and its lithospheric setting. The interior ice reservoir is the portion of the ice sheet below the ice divide where the ice sheet is attached to its bed. This interior ice is penetrated and drained by the fast moving ice streams which flow between regions of relatively stagnant ice. The open arrows indicate the gliding of ice over its bed from the onset region toward the ice shelf. Beneath the ice streams the lubricating till is illustrated. The extensional nature of the underlying lithosphere is indicated by the sediment filled grabens beneath the ice streams.
These first blogs were written at the time of the publication of the first of the IPCC reports. One of the most controversial scientific issues at the release of the report was whether or not the melting of ice on land had been underestimated. This has continued to be an item of discussion in the scientific community. (I am of the opinion that most of our representation of the melting of land ice in models has been underestimated.)
I found a recent news article in EOS, The Transactions of the American Geophysical Union especially interesting. The article is entitled West Antarctic Links to Sea Level Estimation by David Vaughan, John Holt, and Donald Blankenship. This is a article that discusses the issues of understanding the evolution of the glaciers that make up the West Antarctic Ice Sheet. One of the first things that struck me is how dependent we are on satellite data to get information on the ice sheets. This is partly due to their remote location, but also due to the large spatial extent of the glacier and the need to have coordinated measurements of the glacier in order to determine the speed of movement, and hence, to calculate the mass balance.
The article by Vaughn, Holt, and Blankenship is careful to pose their discussion of the glaciers in terms of possible processes. For instance, given the dependence on the short-term satellite record, their is the question of whether or not we are seeing short-term variability or melting due to global warming. In this article, the authors focus on the Amundsen Sea Embayment ice sheet. They point out that atmospheric warming is not sufficient to cause melting of ice on the surface of the ice sheet. There is, however, increasing evidence that the warming of the ocean, especially at the bottom of the ice shelf that extends out into the ocean, is accelerating the melting of the glacier, and leading to the increased speed of the glacial movement.
A little more than a year ago I was lecturing at a summer school where Andrew Shepherd gave a fascinating series of lectures on the Pine Island Glacier. This is another glacier in West Antarctica where there has been increasing motion and melting. These talks provided a convincing argument that warming in the ocean was not only contributing to the melting at the shoreline, but that the heating was being diffused into the interior of the glacier --- accelerating the motion. (Here are some cool figures and information from Shepherd and Wingham's 2007 paper in Science Recent Sea-Level Contributions of the Antarctic and Greenland Ice Sheets)
Here is a link to a web page from the European Space Agency, that talks about the space-based radar observations that are used to study these remote glaciers. On the right of this page are some links to some interesting sites, some with pictures of melt rates in the glaciers of the West Antarctic Ice Sheet.
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Do you know what a carbon credit is, and where to buy one?
What countries are doing what voluntarily?
"having to pay" means in the future, if the UN gets it's way.
also expressed skepticism about climate fears in 2007. "It is time for a reality check," Everett testified to Natural Resources Committee in the U.S. Congress on April 17, 2007. "Warming is not a big deal and is not a bad thing," Everett emphasized. "The oceans and coastal zones have been far warmer and colder than is projected in the present scenarios of climate change," Everett said. "In the oceans, major climate warming and cooling is a fact of life, whether it is over a few years as in an El Niño or over decades as in the Pacific Decadal Oscillation or the North Atlantic Oscillation. Currents, temperatures, salinity, and biology changes rapidly to the new state in months or a couple years. These changes far exceed those expected with global warming and occur much faster. The one degree F. rise since about 1860, indeed since the year 1000, has brought the global average temperature from 56.5 to 57.5 degrees. This is at the level of noise in this rapidly changing system," Everett explained. "I would much rather have the present warm climate, and even further warming, than the next ice age that will bring temperatures much colder than even today. The NOAA PaleoClimate Program shows us that when the dinosaurs roamed the earth, the earth was much warmer, the CO2 levels were 2 to 4 times higher, and coral reefs were much more expansive. The earth was so productive then that we are still using the oil, coal, and gas it generated," he added. "More of the warming, if it comes, will be during winters and at night and toward the poles. For most life in the oceans, warming means faster growth, reduced energy requirements to stay warm, lower winter mortalities, and wider ranges of distribution," he explained. "No one knows whether the Earth is going to keep warming, or since reaching a peak in 1998, we are at the start of a cooling cycle that will last several decades or more," Everett concluded. Everett also worked for the National Marine Fisheries Service Division Chief for Fisheries Development in the 1970s and he noted that the concern then was about how predicted global cooling would impact the oceans.
source
Norway: Geologist/Geochemist Dr. Tom V. Segalstad, a professor and head of the Geological Museum
at the University of Oslo and formerly an
expert reviewer with the UN IPCC:
"It is a search for a mythical CO2 sink to explain an immeasurable CO2 lifetime
to fit a hypothetical CO2 computer model that purports to show that an impossible amount of fossil fuel burning is heating the atmosphere.
It is all a fiction."
I took a look at the article referenced here:
89. latitude25 7:46 AM PST on December 20, 2007
Scientists are finding entire forests buried under some glaciers.
Not only showing that it was warmer,
but warmer for much longer than they had thought.
I believe the first sentence is a quote from the article and the second is latitude25's comment.
Anyway, the article says that the forest was there several thousand years ago. Anyone know just how many? Or, how mature the forest was? Or, how big an "entire forest" is? Or, the Rockies being geologically active, whether the elevation has changed since that time? Or, was it in a protected valley that lost it's protection due to geological activity? Or, if there is evidence there of geothermal vents? Or, if the glacier, rather than shrinking, simply shifted (again, perhaps, as a result of geological activity)?
I'm not trying to be argumentative. I'm just wondering at all the possible explanations for there being an "entire forest" under a glacier. My brain does stuff like that - makes it hard to draw definitive conclusions but keeps me seeking.
"Personal beliefs on climate change and rising sea levels should be delayed until just one of the many predictions made since 1985 on the basis of carbon additions to the atmosphere comes true."
Geologist Dr. David Kear, the former director of geological survey at the Department of Science and Industrial Research in New Zealand,
All they mention is several different sites, additional examples and elsewhere, etc
Rockys and elsewhere, but they don't specifically say where elsewhere is.
When you read the rest of the quotes, it seems to imply that it's different glaciers and ice caps all over the world. But the excerpts don't have it in them.
I guess someone could look it up.
Here's the entire quote:
"Additional examples would confirm that, during the Little Ice Age, glacial systems expanded in concert and then withdrew together Because many glacial margins began retreat (A.D. %u20181850%u20131900) before the introduction of significant amounts of human-induced greenhouse gases, at least the initial part of the warming is a natural swing in the climate system. The continued warming and subsequent glacial retreat have uncovered buried forests in the Canadian Rockies (8) and elsewhere that are several thousand years old, which would require that these glaciers were once smaller than their present size. Such observations help define the range of natural climate variability."
DuBois is very skeptical of climate computer models predicting doom. "I know something about how misleading models can be, and the fact that their underlying assumptions can completely predetermine the results of the model. If the major climate models that are having a major impact on public policy were documented and put in the public domain, other qualified professionals around the world would be interested in looking into the validity of these models," DuBois wrote to EPW on May 17, 2007. "Right now, climate science is a black box that is highly questionable with unstated assumptions and model inputs. It is especially urgent that these models come out in the open considering how much climate change legislation could cost the United States and the world economies. Ross McKitrick's difficulty in getting the information from [Michael] Mann on his famous ‘hockey stick' [temperature] curve is a case in point which should be a scandal not worth repeating. The cost of documenting the models and making them available would be a trifle; the cost of not doing so could be astronomical," DuBois wrote. "I headed up a project to model computer networks (to see how they will perform before they are built) for NASA's International Space Station (including the ground stations around the globe). If I had suggested a $250 million network for the ISS and said that I was basing this recommendation on my modeling but the models were not available for inspection, I would have been laughed out of the auditorium in Houston."
Mainly they're talking about Greenland, though.
That article was posted two days ago but Lowell's paper is from 2000 and the Luckman article referenced for the "entire forest" quote is from 1995. Luckman, it turns out, has done lots of work linking global climate events throughout the Holocene using glacier data - I can't read anything but the abstracts, of course (LOL), but it is interesting.
Thanks for sending me down the rabbit hole, anyway - it's been fun.
But what would be the point of that?
We have consensus and it's been settled. ;-)
James Woudhuysen, a professor of Forecasting and Innovation at De Montfort University in Britain,
"This episode in history I think will go down as marking the reverse of Galileo and Copernicus, the end of the Age of Reason, and it's frightening," Lavin concluded.
Biochemistry researcher Dr. Thomas Lavin, who is a physician who holds patents regarding physical, chemical, and biological sciences and has conducted peer-reviewed research and experiments,
"And so scientists use theoretical concepts like ‘flux adjustments' to make the models agree with reality. When models about the future climate are in agreement, ‘it says more about the self-regulating group psychology of the modeling community than it does about global warming...'"
Mathematician David Orrell dismissed long-term climate models as unreliable.
"There are several disturbing aspects of the IPCC report which indicate that the conclusions are based on serious misconceptions about the behavior of the Earth," ...."The report reflects little understanding of the dynamic relation between the Earth, the Sun and the Cosmos. In these circumstances it is incredible that some leaders of scientific societies and academies have tried to use their authority to demand acceptance of the IPCC report," ...."Scholarship is being driven by media and media attention and this is a terrifying state of affairs. You can get all the money in the world if the research you're doing is related to climate change... if you say climate change isn't caused by man it's caused by the sun, it doesn't get any money at all."
Emeritus Professor Lance Endersbee, a former dean of engineering and pro-vice chancellor at Monash University
"The primary body tasked with advising government policy makers about global warming is the IPCC (Intergovernmental Panel on Climate Change). Policy makers generally regard the IPCC as authoritative. The IPCC bases its analyses on peer-reviewed research, but it does no checking of that research itself. Yet most peer-reviewed research is not properly checked prior to its publication. In other words, most of the research that is relied upon by the IPCC, and thus government policy makers, has never been properly checked. That probably seems incredible; it is unfortunately true."
Mathematical researcher Douglas J. Keenan,
"There are several hundred thousand scientists in the world. And the people who wrote the [UN IPCC] report that received a lot of publicity in February consisted of 33 policy makers, and the authorship of the entire IPCC report consists of 143 people. And that's hardly representative of the entire meteorological word," ..."The validity of a scientific concept is not a matter of how many people vote for it or against it. It's a matter of the evidence upon which it's based. And the truth is there is no real tangible evidence of the connection between CO2 and global warming,"
Geologist Dr. Don J. Easterbrook, Emeritus Professor at Western Washington University
"I consider the part of the IPCC report, which I can really judge as an expert, i.e. the reconstruction of the paleoclimate, wrong,"
Paleoclimate expert Augusto Mangini of the University of Heidelberg in Germany
"As we have explained in 2006, Vostok ice core records show that the carbon dioxide concentration averaged over a few centuries has been correlated with temperature at least for half a million of years. However, we know for sure that the temperature was the cause and the CO2 concentration was its consequence, not the other way around. It follows that the greenhouse effect hasn't been important in the last half a million of years," Motl wrote. "For whatever reason, some people are not willing to accept this obvious conclusion. That's why they invent various bizarre verbal constructs to circumvent the otherwise inevitable conclusion,"
Former Harvard University Physicist Dr. Lubos Motl, a string theorist who is currently a professor at Charles University in the Czech Republic
"It is my firm belief that the United Nations Intergovernmental Panel on Climate Change, politicians, some scientists, multinational corporations, environmentalists, moviemakers, and news media are making false claims regarding the effects of humans on the atmosphere,"
Senior Meteorologist Jeff Halblaub of WSI Corporation which provides weather-driven business solutions to such clients as CNN, FOX, NBC, American Airlines, Delta, and FedEX,
Link
It’s always interesting to read about what real science comes down to instead of some none sense poorly backed allegations. Some people will deny the house is burning even if it is filled with smoke; it’s the way the human mind works, there is protection mechanism that kicks in, and their mind simply refuse to admit that there is a life threatening situation going on.
Remember in the movie Titanic, the 3 guys having a brandy on the lower decks? Their mind did not really believe that the boat was sinking until the water rushed down on them…
I hope, some of you will recognize themselves and finally open an eye to look around…
It’s all in good spirit… No hard feelings…
Merry Christmas and happy holydays to all of you…
Ands thats cool too..It dont change the Facts or Planetary condition,but it reassures the self that all is well...and will remain so.
Or Not?
Merry Xmas to you and yours. Pat
Who is Reid Bryson? Emeritus Professor and founding chairman of the University of Wisconsin Department of Meteorology (now the Department of Oceanic and Atmospheric Sciences), identified by the British Institute of Geographers as the most frequently cited climatologist in the world, the "father of the science of modern climatology."
Bryson was one of the first climatologists to suggest a connection between human activity and climate change, 40 years ago. At the time, his ideas were laughed at. Bryson wasn't talking about carbon dioxide as a means of changing climate, but rather land use changes. Doctor Bryson doesn't believe CO2 is driving climate change. He believes that the data fed into computer models overemphasizes carbon dioxide and handles water vapor poorly. Is he right? Certainly he's not in line with the "consensus." That's okay. The science of AGW can withstand challenges if it's accurate, and if it's not, it needs to be challenged.
But questioning the science does not fit into the "disaster de jour" crowds thinking.
They want to believe in each and every disaster de jour,
no matter how many times those disasters have been proven wrong in the past,
they greet each new one with the same reflex reaction
"It must be true, it's an imminent disaster de jour."
Questioning the science?
Holding the science accountable?
The facts be damned.
MERRY CHRISTMAS
Want me to make one up. ;-)
By posting your conclusion, "Not only showing that it was warmer,
but warmer for much longer than they had thought" based on that bit of information without knowing the answers to those questions, it is clear that you already did - for yourself, at least - and that your answers satisfy you. It's not good enough for me, though, so I'll keep looking. Thanks :)
So it was obvious that it was my opinion, and you actually caught it.
good for you!
Hogbom and Arrhenius are given credit for discovering the whole CO2, warming thing.
But they wrote that back in the late 1800's, early 1900's.
Why didn't the climatologists listen to them in the 1970's?
and why all of a sudden are Hogbom and Arrhenius correct now
when they were not correct in the 70's?
Link
U.S. Senate Report: Over 400 Prominent Scientists Disputed Man-Made Global Warming Claims in 2007
(from Mobal's post in the Doctor's blog)
Astronomers Monitor Asteroid To Pass Near Mars
ScienceDaily (Dec. 21, 2007) — Astronomers funded by NASA are monitoring the trajectory of an asteroid estimated to be 50 meters (164 feet) wide that is expected to cross Mars' orbital path early next year. Observations provided by the astronomers and analyzed by NASA's Near-Earth Object Office at the Jet Propulsion Laboratory in Pasadena, Calif., indicate the object may pass within 30,000 miles of Mars at about 6 a.m. EST (3 a.m. PST) on Jan. 30, 2008.
Link
Stay cool :)
Jer
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