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Popular press once again misconstrues results from scientific paper on sea level rise by 2100

From RealClimate.org

How much will sea level rise?
Filed under: — group @ 8:09 PM

… is the question people have been putting a lot of thought into since the IPCC AR4 report came out. We analysed what was in the report quite carefully at the time and pointed out that the allowance for dynamic ice sheet processes was very uncertain, and actually precluded setting a upper limit on what might be expected. The numbers that appeared in some headlines (up to 59 cm by 2100) did not take that uncertainty into account.

In a more recent paper, our own Stefan Rahmstorf used a simple regression model to suggest that sea level rise (SLR) could reach 0.5 to 1.4 meters above 1990 levels by 2100, but this did not consider individual processes like dynamic ice sheet changes, being only based on how global sea level has been linked to global warming over the past 120 years. As Stefan discussed, any non-linear or threshold behavior of ice sheets could lead to sea level rising faster than this estimate. Thus, otherwise quite conservative voices have been stressing the 'unknown unknown' nature of this problem and suggesting that, based on paleo-data (for instance), it was really hard to rule out sea level rises measured in feet, and not in inches. (Note too, the SLR is very much a lagging indicator, and will continue for centuries past the time that atmospheric temperatures have stabilised).

The first paper to really try and assess the future limits on dynamic ice sheet loss appeared in Science this week. Pfeffer et al looked at the exit glaciers for Greenland and West Antarctica and made some back of the envelope calculations of how quickly the ice sheets could dynamically drain.

Good news: they rule out more than 2 meters of sea level coming from Greenland alone in the next century. This is however more than anyone has ever suggested and would be comparable to the amount that disappeared at the Eemian (125,000 years ago) (see this post for more on that).

Bad news: they can't rule out up to 2 meters in total.

In summary, they estimate that including dynamic ice sheet processes gives projected SLR at 2100 somewhere in the 80 cm to 2 meter range, and suggest that 80 cm should be the 'default' value. This is remarkable in a number of ways - first, these are the highest estimates of sea level rise by 2100 that has been published in the literature to date, and secondly, while they don't take into account the full uncertainty in other aspects of sea level rise considered by IPCC, their numbers are significantly higher in any case. And this week the Dutch 'Delta Commission' published its estimate of sea level rise that the Dutch need to plan for (p111): 55 to 110 cm globally and a bit more for Holland, based on a large number of scientists' input.

Lest readers think this is no big deal, the estimates for the number of people who would be affected by 1 meter of sea level rise is more than 100 million - mainly in Asia. Of some recent relevance is the fact that the storm surge caused by Gustav in New Orleans was within 1 foot of the top of the levees. Another 3 ft caused by global sea level rise would have put a lot more water into the 'bowl'.

Thus better estimates of sea level rise from ice sheets remain a high priority for the climate community. More sophisticated models and deeper understanding are coming along and hopefully those results will be out soon.

We were going to leave it at that, but we've just seen the initial media coverage where this result is being spun as a downgrading of predictions! (exemplified by this Reuters piece, drawing mainly from the U. Colorado press release). This is completely backwards. We stress that no-one (and we mean no-one) has published an informed estimate of more than 2 meters of sea level rise by 2100. Tellingly, the statement in the paper that suggests otherwise has no reference.

There have certainly been incorrect assertions and headlines implying that 20 ft of sea level by 2100 was expected, but they are mostly based on a confusion of a transient rise with the eventual sea level rise which might take hundreds to thousands of years. And before someone gets up to say Al Gore, we'll point out preemptively that he made no prediction for 2100 or any other timescale. The nearest thing I can find is Jim Hansen who states that "it [is] almost inconceivable that BAU climate change would not yield a sea level change of the order of meters on the century timescale". But that is neither a specific prediction for 2100, nor necessarily one that is out of line with the Pfeffer et al's bounds.

Thus, this media reporting stands as a classic example of how scientists get caught up trying to counter supposed myths but end up perpetuating others, and miss an opportunity to actually educate the public. The problem is not that people think that we will get 6 meters of sea level rise this century, it's that they don't think there'll be anything to speak of. Headlines like that in the Reuters piece (or National Geographic) are therefore doing a fundamental disservice to the public understanding of the problem.

Link to post: http://www.realclimate.org/index.php/archives/2008/09/how-much-will-sea-level-rise/

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James Hansen gives testimony in Kingsnorth trial in defense of Greenpeace protesters

Kingsnorth trial day three: world's leading climate scientist gives evidence

Posted by bex on the Greenpeace blog on 3 September 2008.

See all trial updates or sign up to get them by email.

This is a difficult blog to write -- mostly because I'm not sure what to leave out. Today, at the Kingsnorth trial, the world's leading climate scientist told the court that emissions from Kingsnorth led to damage to property worldwide, as well as the extinction of species and the creation of climate change refugees. Gordon Brown, he said, should announce a moratorium on all new coal plants without carbon capture and storage (CCS).

Another witness -- an authority on climate change impacts in the UK -- said all citizens and governments needed to "act with urgency". And two of the defendants, Emily and Kevin, gave impressive testimonies about why they took the action they did. And there's nowhere near enough space to write about it all.

The talk over the morning tea and toast though was all about Jim Hansen. To give you a sense of what his appearance as a defense witness means to the defendants, I should explain that Hansen is a bit of a hero to climate campaigners. This is the man who introduced much of the world to the idea of climate change 20 years ago, when he famously stood up in front of Congress and warned them about it. He's spent much of his time since warning a succession of U.S. Vice Presidents, including Al Gore, about the same thing. Like I said, a bit of a hero -- and he didn't disappoint today.

More on that in a bit. First up was Dr Geoffrey Meaden, an eloquent defence witness with so many letters after his name that I lost track after BSc, BEd, MSc and Phd. In the course of his evidence (via video link from Brazil), he confirmed that the examples of climate change impacts given by the defendants are 'true circumstances'.

"It is overwhelmingly perceived," he said, "by the defendants, the scientific community and myself" that the causes of climate change are caused by humans. There's an increasing urgency, he said, for all citizens and governments to take action.

Within five years, said Dr Meaden, there could be no summer ice left in the Arctic. Ironically, he said, Kingsnorth will be 'extremely vulnerable' to flooding due to climate change.

"The situation is so urgent that unless we act immediately to rapidly reduce greenhouse gas emissions, by the next century we may have to abandon up to 20 per cent of Kent to the sea... It behooves us to act with urgency."

A lot of the evidence today -- from both Dr Meaden and Professor Hansen -- was quite technical, looking at the parts per million of carbon dioxide concentrations in the atmosphere, tipping points and feedback mechanisms. After explaining tipping points in a scientific context, Dr Meaden told the jury that some have suggested that "the most urgent tipping point is a change in human behaviours and actions."

Then Emily took the stand, and introduced herself and how she'd come to be involved with Greenpeace. Emily explained that whatever emissions are in the atmosphere now will have impacts for years to come. When asked why she climbed down the chimney, she said, "I felt very strongly that I wanted to do that." And when the pictures of her hanging off the top of Kingsnorth's smokestack were handed out, I noticed at least a couple of jurors drawing breath.

Kevin was next and introduced himself as a rope access worker from Wiltshire who'd become concerned about climate change back in the '80s. Kevin's questions focused mostly on the safety aspects of the direct action.

Just after 2 p.m., it was Professor James Hansen's turn. The public gallery and press area were packed, and news crews were waiting outside. I'd had the slightly surreal experience of walking down Maidstone High Street with Hansen on the way to the trial and, while he seemed gentle and self-effacing in person, on the stand he had a lot of gravitas. Not surprising, I suppose, for someone who's testified multiple times to the U.S. Senate and House of Representatives.

Hansen has been studying the climatology of various planets for over 30 years, and has spent the last 20 specialising in the Earth's climate. He managed to say such a huge amount worth repeating in his hour and a half on the stand that I'm going to resort to putting his main points in a list, in the hope you'll read them:

* Out of every country on earth, the U.K. bears the most responsibility for historical CO2 emissions in the atmosphere per person (followed by the U.S., then Germany).
* We've already passed a safe proportion of carbon dioxide in the atmosphere, and we need to roll it back. It can still be done, but only if we get coal out of the system as quickly as possible -- by putting a moratorium on all new plants without carbon capture and storage and phasing out old ones.
* If we carry on with business as usual, we'll cause the extinction of one million 
species. Proportionately, several hundred of these species extinctions
could be associated directly with Kingsnorth power station.
* He agreed with Al Gore's statement: "I can't understand why there aren’t rings of young people blocking bulldozers and preventing them from constructing coal-fired power stations".
* Somebody -- the leader of the U.K., Germany or the U.S. -- needs to "step up," take leadership and announce a moratorium on new coal plants.
* The atmosphere currently contains around 385 parts per million (ppm) of CO2, rising by 2 ppm per year. Most targets to stop climate change suggest a target of 450 ppm, and a two degree rise in temperature as safe upper limits. To meet those targets will require our world to change dramatically.
* But the safe level is no more than 350 ppm -- and may be less. And a rise of two degrees is "a recipe for global disaster and not salvation." The last time the earth was more than two degrees warmer than it is now, there was a 25-m sea level rise.
* "The simple but shocking truth is we have gone too far. We place our planetary system, inhabitants and future generations in grave peril... If we are to preserve the planet that civilisation has grown on, we have to go back."
* "Humans are now in charge of atmospheric CO2 and the global climate... It's up to those of us alive today to take the bold steps needed."
* If we carry on as we are at the moment, the Greenland ice sheets will melt, leading to a sea level rise of at least two metres this century. Hundreds of millions of people will be come refugees. There will be mass species extinction and ecosystem collapse.
* If the ice in the (vulnerable) Western Arctic* West Antarctic ice sheet melts, the sea levels would rise by around six metres.
* The complete loss of Arctic sea ice in the summer is now inevitable. The impacts on China, Kent, Bangladesh and the polar regions are enormous.

(* Sorry, my error in typing up my notes.)

It was at this point that I started to feel really sorry for the jury. They're getting, essentially, a crash course in climate change and its impacts from some of the most knowledgeable minds on the subject (Hansen and Meaden) in the world, and some of the most passionate (the defendants). I'd imagine, to some of the jurors, the evidence must seem pretty terrifying. It is terrifying.

Thankfully though, Hansen went on to talk about what could still be done. He was invited to go on stage with Al Gore at Live Earth, he said, and took his grandchildren along. How many species do we need to save, he asked them. "All of them," said his grand-daughter. ("Me too," said his grand-son.)

We can't save all of them but we can still save most, he said. If we continue with business-as-usual our descendants will be "left with a much more desolate planet and much less biodiversity". But, although "there's just barely still time", we need an immediate moratorium on the construction of all new coal- fired power plants (without CCS) and the phasing out of existing coal plants to get back to 350 ppm. And somebody -- whether it's the U.K., U.S. or Germany -- needs "to stand up."

If you've made it this far, you're obviously pretty interested, so I'll tell you that I had the good fortune to interview Hansen today -- and that interview will be featuring in our next podcast. I'll also tell you that tomorrow, our last two defendants, Huw and Will, will be taking the stand, along with Conservative advisor and former Ecologist editor Zac Goldsmith.

For now, I'm off to raise a glass to Meaden, Hansen, the defendants and everyone else who is (ahem) taking a stand.

Link to blog article: http://www.greenpeace.org.uk/blog/climate/kingsnorth-day-three-trial-jim-hansen-20080903

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Brauer, Haug, Dulski, Sigman, Negendank: An abrupt wind shift in western Europe at the onset of the Younger Dryas cold period

Letter abstract

Nature Geoscience 1, 520-523 (2008)
Published online: 1 August 2008 | doi:10.1038/ngeo263

An abrupt wind shift in western Europe at the onset of the Younger Dryas cold period

Achim Brauer1, Gerald H. Haug2,3, Peter Dulski1, Daniel M. Sigman4 & Jörg F. W. Negendank1

The Younger Dryas cooling 12,700 years ago is one of the most abrupt climate changes observed in Northern Hemisphere palaeoclimate records1, 2, 3, 4. Annually laminated lake sediments are ideally suited to record the dynamics of such abrupt changes, as the seasonal deposition responds immediately to climate, and the varve counts provide an accurate estimate of the timing of the change. Here, we present sub-annual records of varve microfacies and geochemistry from Lake Meerfelder Maar in western Germany, providing one of the best dated records of this climate transition5. Our data indicate an abrupt increase in storminess during the autumn to spring seasons, occurring from one year to the next at 12,679 yr BP, broadly coincident with other changes in this region. We suggest that this shift in wind strength represents an abrupt change in the North Atlantic westerlies towards a stronger and more zonal jet. Changes in meridional overturning circulation alone cannot fully explain the changes in European climate6, 7; we suggest the observed wind shift provides the mechanism for the strong temporal link between North Atlantic Ocean overturning circulation and European climate during deglaciation.

  1. GFZ German Research Centre for Geosciences, Telegrafenberg, D-14473 Potsdam, Germany
  2. Geological Institute, Department of Earth Sciences, ETH Zürich, 8092 Zürich, Switzerland
  3. DFG-Leibniz Center for Surface Process and Climate Studies, Institute for Geosciences, Potsdam University, 14476 Potsdam, Germany
  4. Department of Geosciences, Princeton University, Princeton, New Jersey 08544, USA
Correspondence to: Achim Brauer1 e-mail: brau@gfz-potsdam.de

Link to abstract: http://www.nature.com/ngeo/journal/v1/n8/abs/ngeo263.html

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Extreme and risky action the only way to tackle global warming, say scientists

Extreme and risky action the only way to tackle global warming, say scientists

· Geo-engineering 'better than doing nothing'
· Fake clouds among ideas in Royal Society papers

  • David Adam, environment correspondent, The Guardian, September 1, 2008
Political inaction on global warming has become so dire that nations must now consider extreme technical solutions - such as blocking out the sun - to address catastrophic temperature rises, scientists from around the world warn today.

The experts say a reluctance "at virtually all levels" to address soaring greenhouse gas emissions means carbon dioxide levels in the atmosphere are on track to pass 650 parts-per-million (ppm), which could bring an average global temperature rise of 4C. They call for more research on geo-engineering options to cool the Earth, such as dumping massive quantities of iron into oceans to boost plankton growth, and seeding artificial clouds over oceans to reflect sunlight back into space.

Writing the introduction to a special collection of scientific papers on the subject, published today by the Royal Society, Brian Launder of the University of Manchester and Michael Thompson of the University of Cambridge say: "While such geoscale interventions may be risky, the time may well come when they are accepted as less risky than doing nothing."

They add: "There is increasingly the sense that governments are failing to come to grips with the urgency of setting in place measures that will assuredly lead to our planet reaching a safe equilibrium."

Professor Launder, a mechanical engineer, told the Guardian: "The carbon numbers just don't add up and we need to be looking at other options, namely geo-engineering, to give us time to let the world come to its senses." He said it was important to research and develop the technologies so that they could be deployed if necessary. "At the moment it's almost like talking about how we could stop world war two with an atomic bomb, but we haven't done the research to develop nuclear fission."

Such geo-engineering options have been talked about for years as a possible last-ditch attempt to control global temperatures, if efforts to constrain emissions fail. Critics argue they are a dangerous distraction from attempts to limit carbon pollution, and that they could have disastrous side-effects. They would also do nothing to prevent ecological damage caused by the growing acidification of the oceans, caused when carbon dioxide dissolves in seawater. Last year, the Intergovernmental Panel on Climate Change dismissed geo-engineering as "largely speculative and unproven and with the risk of unknown side-effects".

Dr Alice Bows of the Tyndall Centre for Climate Change Research at the University of Manchester said: "I'm not a huge fan of messing with the atmosphere in an geo-engineering sense because there could be unpredictable consequences. But there are also a lot of unpredictable consequences of temperature increase. It does appear that we're failing to act [on emissions]. And if we are failing to act, then we have to consider some of the other options."

In a strongly worded paper with colleague Kevin Anderson in today's special edition of the society's Philosophical Transactions journal, Bows says politicians have significantly underestimated the scale of the climate challenge. They say this year's G8 pledge to cut global emissions 50% by 2050, in an effort to limit global warming to 2C, has no scientific basis and could lead to "dangerously misguided" policies.

The scientists say global carbon emissions are rising so fast that they would need to peak by 2015 and then decrease by up to 6.5% each year for atmospheric CO2 levels to stabilise at 450ppm, which might limit temperature rise to 2C. Even a goal of 650ppm - way above most government projections - would need world emissions to peak in 2020 and then reduce 3% each year.

Globally, a 4C temperature rise would have a catastrophic impact. According to the government's Stern review on the economics of climate change in 2006, between 7 million and 300 million more people would be affected by coastal flooding each year, there would be a 30-50% reduction in water availability in southern Africa and the Mediterranean, agricultural yields would decline 15-35% in Africa and 20-50% of animal and plant species would face extinction.

Martin Rees, president of the Royal Society, said: "It's not clear which of these geo-engineering technologies might work, still less what environmental and social impacts they might have, or whether it could ever be prudent or politically acceptable to adopt any of them. But it is worth devoting effort to clarifying both the feasibility and any potential downsides of the various options. None of these technologies will provide a 'get out of jail free card' and they must not divert attention away from efforts to reduce emissions of greenhouse gases."

Mike Childs of Friends of the Earth said: "We can't afford to wait for magical geo-engineering solutions to get us out of the hole we have dug ourselves into. The solutions that exist now, such as a large-scale energy efficiency programme and investment in wind, wave and solar power, can do the job if we deploy them at the scale and urgency that is needed."

Link to article: http://www.guardian.co.uk/environment/2008/sep/01/climatechange.scienceofclimatechange2

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A list of posts from August

August 2008 posts:

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Greenland ice sheet notes

Science, 9 May 1997, Vol. 276, No. 5314, pp. 934–937
DOI: 10.1126/science.276.5314.934

Reports

North and Northeast Greenland Ice Discharge from Satellite Radar Interferometry

E. J. Rignot, * S. P. Gogineni, W. B. Krabill, S. Ekholm

Ice discharge from north and northeast Greenland calculated from satellite radar interferometry data of 14 outlet glaciers is 3.5 times that estimated from iceberg production. The satellite estimates, obtained at the grounding line of the outlet glaciers, differ from those obtained at the glacier front, because basal melting is extensive at the underside of the floating glacier sections. The results suggest that the north and northeast parts of the Greenland ice sheet may be thinning and contributing positively to sea-level rise.

E. J. Rignot, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099, U.S.A.
S. P. Gogineni, Radar Systems and Remote Sensing Laboratory, The University of Kansas, 2291 Irving Hill Road, Lawrence, KS 66045-2969, U.S.A.
W. B. Krabill, NASA Goddard Space Flight Center, Wallops Flight Facility, Laboratory for Hydrospheric Processes, Wallops Island, VA 23337, U.S.A.
S. Ekholm, Kort and Matrikelstyrelsen, Geodetic Division, Rentemestervej 8, DK-2400 Copenhagen NV, Denmark
* To whom correspondence should be addressed. e-mail: eric@adelie.jpl.nasa.gov

Link to abstract: http://www.sciencemag.org/cgi/content/abstract/276/5314/934
_________________________________________________________________

Science, 17 February 2006, Vol. 311, No. 5763, pp. 986–990
DOI: 10.1126/science.1121381

Reports

Changes in the Velocity Structure of the Greenland Ice Sheet

Eric Rignot1* and Pannir Kanagaratnam2*

Using satellite radar interferometry observations of Greenland, we detected widespread glacier acceleration below 66° north between 1996 and 2000, which rapidly expanded to 70° north in 2005. Accelerated ice discharge in the west and particularly in the east doubled the ice sheet mass deficit in the last decade from 90 to 220 cubic kilometers per year. As more glaciers accelerate farther north, the contribution of Greenland to sea-level rise will continue to increase.

1 Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 300-319, Pasadena, CA 91109–8099, U.S.A.
2 Center for Remote Sensing of Ice Sheets (CReSIS), University of Kansas, Lawrence, KS 66045, U.S.A.

* To whom correspondence should be addressed. e-mail: eric.rignot@jpl.nasa.gov (E.R), pannir@ku.edu (P.K.)

Link to abstract: http://www.scienceonline.org/cgi/content/abstract/311/5763/986
_________________________________________________________________

Science, 20 June 2008, Vol. 320, No. 5883, pp. 1622–1625
DOI: 10.1126/science.1153929

Reports

Natural Variability of Greenland Climate, Vegetation, and Ice Volume During the Past Million Years

Anne de Vernal* and Claude Hillaire-Marcel

The response of the Greenland ice sheet to global warming is a source of concern notably because of its potential contribution to changes in the sea level. We demonstrated the natural vulnerability of the ice sheet by using pollen records from marine sediment off southwest Greenland that indicate important changes of the vegetation in Greenland over the past million years. The vegetation that developed over southern Greenland during the last interglacial period is consistent with model experiments, suggesting a reduced volume of the Greenland ice sheet. Abundant spruce pollen indicates that boreal coniferous forest developed some 400,000 years ago during the "warm" interval of marine isotope stage 11, providing a time frame for the development and decline of boreal ecosystems over a nearly ice-free Greenland.

1GEOTOP Geochemistry and Geodynamics Research Center–Université du Québec à Montréal, Case Postale 8888, succursale Centre-Ville, Montréal, Québec H3C 3P8, Canada.

* To whom correspondence should be addressed. e-mail: devernal.anne@uqam.ca

Link to abstract: http://www.sciencemag.org/cgi/content/abstract/320/5883/1622

_________________________________________________________________


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Faster Rise In Sea Level Predicted From Melting Greenland Ice Sheet, Based On Lessons From Ice Age

ScienceDaily (Aug. 31, 2008) — If the lessons being learned by scientists about the demise of the last great North American ice sheet are correct, estimates of global sea level rise from a melting Greenland ice sheet may be seriously underestimated.

Writing in the journal Nature Geoscience, a team of researchers led by University of Wisconsin-Madison geologist Anders Carlson reports that sea level rise from greenhouse-induced warming of the Greenland ice sheet could be double or triple current estimates over the next century.

"We're not talking about something catastrophic, but we could see a much bigger response in terms of sea level from the Greenland ice sheet over the next 100 years than what is currently predicted," says Carlson, a UW-Madison professor of geology and geophysics. Carlson worked with an international team of researchers, including Allegra LeGrande from the NASA Center for Climate Systems at Columbia University, and colleagues at the Woods Hole Oceanographic Institution, the California Institute of Technology, University of British Columbia and University of New Hampshire.

Scientists have yet to agree on how much melting of the Greenland ice sheet — a terrestrial ice mass encompassing 1.7 million sq. km — will contribute to changes in sea level. One reason, Carlson explains, is that in recorded history there is no precedent for the influence of climate change on a massive ice sheet.

"We've never seen an ice sheet disappear before, but here we have a record," says Carlson of the new study that combined a powerful computer model with marine and terrestrial records to provide a snapshot of how fast ice sheets can melt and raise sea level in a warmer world.

Carlson and his group were able to draw on the lessons of the disappearance of the Laurentide ice sheet, the last great ice mass to cover much of the northern hemisphere. The Laurentide ice sheet, which encompassed large parts of what are now Canada and the United States, began to melt about 10,000 years ago in response to increased solar radiation in the northern hemisphere due to a cyclic change in the orientation of the Earth's axis. It experienced two rapid pulses of melting — one 9,000 years ago and another 7,600 years ago — that caused global sea level to rise by more than half an inch per year.

Those pulses of melting, according to the new study, occurred when summer air temperatures were similar to what are predicted for Greenland by the end of this century, a finding the suggests estimates of global sea level rise due to a warming world climate may be seriously underestimated.

The most recent estimates of sea level rise due to melting of the Greenland ice sheet by the Intergovernmental Panel on Climate Change (IPCC) suggest a maximum sea level rise during the next 100 years of about 1 to 4 inches. That estimate, Carlson and his colleagues note, is based on limited data, mostly from the last decade, and contrasts sharply with results from computer models of future climate, casting doubt on current estimates of change in sea level due to melting ice sheets.

According to the new study, rising sea levels up to 1/3 inch per year (or 1-2 feet over the course of a century) are possible.

Even slight rises in global sea level are problematic as a significant percentage of the world's human population — hundreds of millions of people — lives in areas that can be affected by rising seas.

"For planning purposes, we should see the IPCC projections as conservative," Carlson says. "We think this is a very low estimate of what the Greenland ice sheet will contribute to sea level."

The authors of the new Nature Geoscience report were able to document the retreat of the Laurentide ice sheet and its contributions to changes in sea level by measuring how long rocks once covered by ice have been exposed to cosmic radiation, estimates of ice retreat based on radiocarbon dates from organic material as well as changes in ocean salinity.

In addition to Carlson and LeGrande, co-authors of the study, which was funded primarily by the National Science Foundation, are Gavin A. Schmidt of Columbia University, Delia W. Oppo of the Woods Hole Oceanographic Institution, Rosemarie E. Came of the California Institute of Technology, Faron S. Anslow of the University of British Columbia, Joseph M. Licciardi of the University of New Hampshire, and Elizabeth A. Obbink of UW-Madison.

Journal reference:

  1. Anders Carlson et al. Rapid early Holocene deglaciation of the Laurentide ice sheet. Nature Geoscience, August 31, 2008
Adapted from materials provided by University of Wisconsin-Madison, via EurekAlert!, a service of AAAS.

Link to article: http://www.sciencedaily.com/releases/2008/08/080831151346.htm