‘Counterintuitive finding suggests that unexpected factors may govern a glacier’s response to climate change’

From the University at Buffalo, new evidence that large ice sheets can grow/disappear quickly on decadal scales in response to regional temperature changes. A descriptive video follows.

How fast can ice sheets respond to climate change?

Scientists report that prehistoric glaciers reacted rapidly to a brief cold snap, providing a rare glimpse of glaciers’ response to past climate change

This shows University at Buffalo students Elizabeth Thomas, Sean McGrane and Nicolás Young on Baffin Island (left to right). They were members of a team studying the historical extent of glaciers on the Arctic island. Credit: Jason Briner

BUFFALO, N.Y. — A new Arctic study in the journal Science is helping to unravel an important mystery surrounding climate change: How quickly glaciers can melt and grow in response to shifts in temperature.

According to the new research, glaciers on Canada’s Baffin Island expanded rapidly during a brief cold snap about 8,200 years ago. The discovery adds to a growing body of evidence showing that ice sheets reacted rapidly in the past to cooling or warming, raising concerns that they could do so again as the Earth heats up (or cools down – Anthony).

“One of the questions scientists have been asking is how long it takes for these huge chunks of ice to respond to a global climate phenomenon,” said study co-author Jason Briner, PhD, a University at Buffalo associate professor of geology. “People don’t know whether glaciers can respond quickly enough to matter to our grandchildren, and we’re trying to answer this from a geological perspective, by looking at Earth’s history.”

This shows Ayr Lake, Baffin Island, Canada. UB geologists studying this remote region found that the island’s glaciers reacted rapidly to past climate change, providing a rare glimpse into glacier sensitivity to climate events. Credit: Jason Briener

“What we’re seeing,” he added, “is that these ice sheets are surprisingly sensitive to even short periods of temperature change.”

Briner’s colleagues on the study included lead author Nicolás Young, who worked on the study as part of his PhD at UB and is now a postdoctoral researcher at Columbia University’s Lamont-Doherty Earth Observatory; Dylan H. Rood of the Scottish Universities Environmental Research Centre and the University of California, Santa Barbara; and Robert C. Finkel of UC Berkeley.

The research, scheduled to appear in Science on Sept. 14, found that mountain glaciers on Baffin Island, along with a massive North American ice sheet, expanded quickly when the Earth cooled about 8,200 years ago.

The finding was surprising because the cold snap was extremely short-lived: The temperature fell for only a few decades, and then returned to previous levels within 150 years or so.

“It’s not at all amazing that a small local glacier would grow in response to an event like this, but it is incredible that a large ice sheet would do the same,” Young said.

This video detailing the findings and the information in this press release is embargoed until 2 p.m. U.S. Eastern Time on Thursday, Sept. 13, 2012.

To conduct the research, Briner led a team to Baffin Island to read the landscape for clues about the pre-historical size and activity of glaciers that covered the island.

Moraines — piles of rocks and debris that glaciers deposit while expanding — provided valuable information. By dating these and other geological features, the scientists were able to deduce that glaciers expanded rapidly on Baffin Island about 8,200 years ago, a period coinciding with a short-lived cold snap.

The researchers also found that Baffin Island’s glaciers appeared to have been larger during this brief period of cooling than during the Younger Dryas period, a much more severe episode of cooling that began about 13,000 years ago and lasted more than a millennium.

This counterintuitive finding suggests that unexpected factors may govern a glacier’s response to climate change.

With regard to Baffin Island, the study’s authors say that while overall cooling may have been more intense during the Younger Dryas, summer temperatures may have actually decreased more during the shift 8,200 years ago. These colder summers could have fueled the glaciers’ rapid advance, decreasing the length of time that ice melted during the summer.

Detailed analyses of this kind will be critical to developing accurate models for predicting how future climate change will affect glaciers around the world, Briner said.

###

The study was funded by the National Science Foundation.

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35 Responses to ‘Counterintuitive finding suggests that unexpected factors may govern a glacier’s response to climate change’

  1. Mark Smith says:

    “huge chunks of ice to respond to a global climate phenomenon”
    They look up website and do what it tells them to.

  2. “It’s not at all amazing that a small local glacier would grow in response to an event like this, but it is incredible that a large ice sheet would do the same,”

    It’s not incredible at all. In fact its rather obvious. When snow/ice accumulates on an icesheet, elevation increases and temperatures fall, resulting in both an increase in precipitation and an increase in the percentage of the precipitation that falls as snow. A positive feedback that continues until the mass of the icesheet causes it spread outwards, rather than accumulate upwards.

  3. Philip Finck says:

    I haven’t read the paper, however there is a huge difference between the response of remnant glaciers such as those on Baffin Island and continental glaciers in places such as Greenland or Antarctica. They are completely different beasts. Even melt rates and retreat of the Laurentide Ice Sheet cannot be used to model retreat of say Greenland and Antarctica. The Laurentide ice sheet was retreating from positions more than half way to the Equator. This implies numerous differences; length of days, intensity of sun, way warmer potential summers which would fuel much more rapid retreat in the southern extents of the ice sheet…….. just on and on.

    It is well known that heavy winter snowfall in a restricted area with local valley glaciers may cause an increase rate of flow at the end of the glacier. Whether the glacier advances, remains stationary, or even retreats then depends on the rate of melt and the resulting mass balance. One might also want to be careful in over interpreting behaviour of remnant small glaciers. Removal of the continental glacier may have resulted in drastic changes in the local environment between say the Younger Dryas and 8200 years ago.

    Having said this I should read the paper when available.

  4. Ian H says:

    They observed rapid advance. But did they ever observe rapid decline? The way things are written it is suspiciously obscure on this point. It is implied, but never stated. Note that as glacier formation and melting occur by very different processes, the observation of rapid advance is not evidence for the possibility of equally rapid decline. That seems to be what they want us to think though.

  5. MarkW says:

    Looking at it another way.
    If this study is correct and small changes in temperature can result in quick and dramatic changes to glaciers.
    Then the fact that we aren’t seeing quick and dramatic changes in glaciers is evidence that there have been no significant changes to temperature.

  6. Steve R says:

    I think we should consider the possibility that the rapid response of the glacier might have less to do with temperature than we would otherwise think. Imagine that for some reason warm tropical moisure were diverted to high arctic latitudes and into an ice free Arctic ocean. The adjacent continental landmasses could easily be transformed from a Arid climate to a climate of extreme blizzard conditions, with yearly snowfalls perhaps as high as in the Cascades. Just a few weeks back, here in WUWT, there was an unusual study posted that came to the puzzling conclusion that the Arctic Ocean may have been somewhat warmer at the time of peak glaciation.

    What do you think? Is there any physical reason how a portion of the Gulf stream for instance might have been diverted to much higher latitude? Could it be a possible response to increased sea levels? Then maybe as sea levels fall at peak glaciation, the Gulf stream is forced sowthward again, the Arctic freezes over, and the continental galciers become starved of snowfall? Could the tens of thousands of year glaciation cycles somehow be controlled by changes in sea level, leading to alternating patterns of tropical currents intruding into the Arctic Ocean, leading to alternative thawing and refreezing of the Arctic, transforming the adjacent landmasses from blizzard-like snowfall rates into semi arid snowfall rates?

  7. u.k.(us) says:

    Last time I researched glacier behavior (about 2 years ago), it seemed the consensus was that we know very little about it.
    Has that changed ?

  8. Caleb says:

    RE:Steve R says:
    September 13, 2012 at 3:29 pm

    Steve, I recall reading, back before the Global Warming Scare even began, that some felt the Arctic Ocean was ice-free during the ice ages. This old idea had some similarities with your idea that, “The adjacent continental landmasses could easily be transformed from a Arid climate to a climate of extreme blizzard conditions, with yearly snowfalls perhaps as high as in the Cascades.”

  9. GlynnMhor says:

    More evidence that too little is known about glacial phenomena to be able to make reliable predictions.

  10. Bill Illis says:

    If you want a visual of the 8,200 year old cold event, here it is using the Greenland and Antarctica ice core records.

    Although it certainly sticks out in the Holocene temperature record, it was not that remarkable. Greenland temps (using the proper formula) fell by about 1.5C to 2.0C for a short 150 years while Antarctica may have had a longer downturn lasting about 800 years of 1.0C or so.

    Polar amplification indicates global temps probably fell by about half these levels during the period. CO2 at 100 year resolution did not change at all through this time.

    http://s7.postimage.org/3rslytwfv/8200_Year_Old_Cold_Event.png

  11. BioBob says:

    My bullcrap meter is pegged. Someone please explain how they purport to date all of their observations to 8200 years ago versus 9000 or 820,000 years ago – on piles of rock shifted hither and yon by potentially known and unknown processes ?

    Give me a break. I am sick and tired of the most tenuous proxies assigned precision of decades, centuries and tenths of a degree C when the reality is that we do not know squat with any certainty.

  12. sophocles says:

    rapid growth of glaciers is well documented from the LIA—esp. with respect to the european alpine glaciers. Brian Fagan draws on those historical accounts in his book “The Little Ice Age: How Climate Made History, 1300-1850.” (worth a read).

    With that recent knowledge, this paper should not be any surprise to anyone.

  13. Jack G. Hanks says:

    Speaking of ice, MASIE shows the arctic ice extent at 3.5 million km^2.

  14. jorgekafkazar says:

    One way to tell you’re being lied to is when common terms are used in new ways to mean something else, without warning and without explanation. Here’s the precise definition of cold snap:

    cold snap, n., (Earth Sciences / Physical Geography) a sudden short spell of cold weather*

    Weather, got it? A cold snap lasts a day, two at most. Authors who twist “cold snap” to mean a decadal shift in temperatures are being misleading, perhaps unconsciously, perhaps not. Note that BBC media referred to an entire bitterly cold winter season as “a cold snap.”

    See Steve R’s comment, above, regarding humidities. They probably didn’t consider that, at all. NB: the mechanisms for glacier formation and glacier retreat are sufficiently dissimilar that their extrapolation of rapid ice change from cold conditions to warm conditions is probably invalid, as Ian H states in his comment, above.

    *Collins English Dictionary – Complete and Unabridged © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003 [via Free Online Dictionary, http://www.thefreedictionary.com/%5D

  15. CodeTech says:

    I still say these people would never write the majority of their inane glacier studies if they’d simply grown up in a WINTER climate. I mean winter. I mean places that experience -40. There they would learn that it takes a lot longer to melt large expanses of ice than they take to freeze. What kind of different studies would we see if they had grown up in Alberta, where it can go from -40 to +15 in an hour, then go right back down again.

    Oh well, no point in ranting… apparently science isn’t about explaining the natural world anymore, it’s about changing peoples’ attitudes and working on “sustainability”.

  16. john robertson says:

    Press release suggests more piffle from bedwetters R us, I wonder what proxy is used to date these morons. Mannian tree rings? When did trees last grow on Baffin? Same time as the petrified stumps on Axel Hieldberg. I swear the average scotch on the rocks drinker has a better grasp of ice behaviour than these “experts”.

  17. Steve R says:

    It seems to me the real reason we don’t have a continental ice sheet today, at least down through the Canadian territories, is lack of snow, not too warm temperatures. Dump 1000 inches of of snow a year on the southern shore of Hudson Bay I’m not guessing it’s not all gonna melt over the next summer.

    On the other hand, if the temperature drops, I don’t really see any mechanism to get the snow piled up quickly enough. It would probably snow even less than it does now. The Laurentide ice sheet at its maximum extended so far out of the arctic that I just can’t believe temperature was the driving factor. Are we supposed to believe arctic-like temps extended south to Ohio and New York? Flora and Fauna living just south of the ice don’t suggest an Artic like climate.
    I think It was an ice sheet driven by extreme precipitation pushing it FAR south of where any normal ice sheet would melt out. The zone of accumulation might have been confined to subarctic latitudes, with a HUGE area of ablation to its southern extent Completely opposite of the Antarctic ice sheet, where only a bit of snow accumulates each year.

  18. jones says:

    Our grandchildren just aren’t going to know what glaciers are………

    Dunno about the snow though…..

  19. D. Cohen says:

    Just take a good look at Greenland’s position with respect to the North Pole. We’re so used to thinking of Greenland as completely covered by glaciers that we don’t pause to notice that it is not really very close to the pole. Lots of Canada and Asia lies further to the north yet is not covered by ice-age-like glaciers like Greenland. Why?

  20. D. Cohen says:

    The last sentence of my first post should read

    Lots of Canada and Asia lies further to the north than southern Greenland yet is not covered by ice-age-like glaciers like Greenland.

  21. Nice presentation that says little or nothing of any scientific value. I’m sure they have some data but would feel more comfortable if they stopped speaking press release and began speaking science.

  22. D. Cohen says:
    September 13, 2012 at 10:33 pm
    Lots of Canada and Asia lies further to the north than southern Greenland yet is not covered by ice-age-like glaciers like Greenland.

    A very good question.

    I’d say glaciers from the high mountains on the east side of Greenland flowed into the central depression, during glacial times, the ice accumulated and the the ice altitude positive feedback I noted above kicked in.

    As Greenland is a depression surrounded by mountains, the ice continued to accumulate and not flow downhill and outward as it would in the Laurentides or Iceland. What stops the ice accumulation altitude positive feedback is the outward and downhill flow of ice and that is restricted in Greenland and isn’t in other locations.

    http://en.wikipedia.org/wiki/File:Topographic_map_of_Greenland_bedrock.jpg

  23. tty says:

    Possibly counterintuitive but won’t surprise anybody who knows his Quaternary Geology. The Younger Dryas cold snap was admittedly longer (about 800 years) but started and ended with very short, steep temperature changes (on the order of 5 degrees in 50 years).
    During these 800 years an ice cap, starting from nothing, grew to cover all the Western Highlands of Scotland and disappeared again.

    Map here: http://ars.sciencedirect.com/content/image/1-s2.0-S0037073808000717-gr1.jpg

    To get a hold on the scale in time and space: imagine a snowdrift starting to collect on top of Ben Nevis in the days of John Lackland, growing to an icecap stretching from Glasgow to well north of Inverness (c. 200 by 50 kilometers) in Cromwell’s time, and then shrinking back to nothing today.

    When I think about it, it rather reminds you of the LIA, but on steroids….

  24. tty says:

    Steve R says:
    “Are we supposed to believe arctic-like temps extended south to Ohio and New York? Flora and Fauna living just south of the ice don’t suggest an Artic like climate.”

    They do actually, though the zone with tundra fauna and flora south of the Laurentide ice was quite narrow, on the order of 100 kilometers or so. In Europe where we don’t have all that warm air from the Gulf to moderate the climate the Steppe-tundra and permafrost extended almost all the way to the Mediterranean.
    The it is certainly true that the moisture from the warm seas to the south is probably the main reason the Laurentide Ice was so much larger than the Eurasian Icecap.

  25. tty says:

    It might be worth mentioning that Baffin’s land is the perfect place to search for rapid changes in glacier extent.
    When the next ice-age starts it will do so in one (or more) of three places: Baffin’s land, northern Ungava or the Putorana mountains of Siberia. These are the only areas in the northern hemisphere that have large flat-lying plateaus with a climate that is very close to the point where the snow doesn’t have time to melt in summer.
    Of these three Baffin’s land is probably the most likely, because, in contrast to most of Arctic Canada (and Siberia) it has fairly heavy precipitation due to nearby open water much of the year in Davis Sound.
    Actually studies on lichens show that much of Baffin’s land was snow-covered for long periods during the Little Ice Age (there are no really old lichen in these areas).
    We probably came quite close to a new Ice Age during the LIA.

  26. vukcevic says:

    I found that some aspects of this area of the North Canada are unique, with a particular relevance to the North Hemispheres climate change; resulting in the first climate related article I wrote in 2009.
    http://www.vukcevic.talktalk.net/NATA.htm
    It was considered as a bit of pure speculation, but now even NASA scientists are ‘speculating’ in the same direction. See links 1 and , 2

  27. Mike Haseler says:

    This is what they seem to be arguing:

    If you turn off the power to the freezer all the ice melts. Therefore, if you increase the power to the freezer with a lot of ice in it, a lot more ice will appear.

    Maybe not the best analogy, but what these people are doing is looking at the transition zone between glacial and interglacial. And then they are trying to suggest that because there is evidence it warms going from interglacial to glacial or cools quickly going from glacial to interglacial. That you must get massive warming from an interglacial to a ??Help there’s not term for a period warmer than an interglacial??? it doesn’t happen.

    Here’s more of the same logic

    … if you cut through a 10m tree once it will fall down 10m. Therefore if you cut it twice it will fall 20m

    …. if your kid drops one boiled egg on your suit, it costs £10 at the dry cleaner, therefore if they drop two it will cost £20.

    …. if you create one global warming scare academics will be flooded with $100million** of grants, so if they create two global warming scares, they will get $200million

    In other words, why the climate may relatively easily (in geological timescales) transit from glacial to interglacial, there is clearly something stopping it getting much warmer than an interglacial and much cooler than a glacial, and that’s because the sensitive area where ice and grow and strink is relatively small. So, once you’ve melting all the easily melting ice, not much more will ever melt.

    **Just a guess.

  28. Philip Finck says:

    Steve R. and Caleb;

    Yes as you note, an ice free arctic ocean that allowed moist air to move over the northern land masses and thus yield very high levels of precipitation in the form of snow is one of several mechanisms suggested for rapid glaciation of the region. It `was’ a good theory and generally accepted as being realistic. However that seems to have been totally forgotten in the new era of glaciology and probably isn’t even mentioned in all the new, artsy – fartsy environmental science degrees being offered at universities. These degrees aren’t worth the paper they are printed on. In fact it is quite common to meet smart geology students that started out in these programs and withdrew to take geology. The reason? They say the courses were crap, little science and just CAGW propaganda.

  29. beng says:

    Don’t see why this is remarkable. It’s been shown that pretty much all the subtropical & tropical mountain glaciers present today formed during the LIA and weren’t present during the MWP.

  30. Kelvin Vaughan says:

    So if increasing CO2 causes warming then removing CO2 can cause an ice Age!

  31. beng says:

    ****
    Steve R says:
    September 13, 2012 at 3:29 pm

    I think we should consider the possibility that the rapid response of the glacier might have less to do with temperature than we would otherwise think. Imagine that for some reason warm tropical moisure were diverted to high arctic latitudes and into an ice free Arctic ocean. The adjacent continental landmasses could easily be transformed from a Arid climate to a climate of extreme blizzard conditions, with yearly snowfalls perhaps as high as in the Cascades.
    ****

    Interesting. Watch Barrow, AK & other Arctic Ocean shore sites for snowfall amounts this autumn. IIRC, Barrow had record snow in autumn 2007.

  32. Fred2 says:

    I don’t know enough to comment intelligently about their hypothesis.

    However I will note that there are engravings/lithographs and paintings of small glaciers in europe and elsewhere that have varied dramatically over the last 300-400 years in how much they extended down their valleys, so I’d not be shocked that it’s possible that given relatively small variations in weather over a couple of decades/centuries that largish ice sheets could A. Form and B. Extend ( and then reverse right back)

    When you read about the various Columbia river “incidents” where massive inland seas drain ,and this I’m sure has happened elsewhere in the world (e.g. perhaps the Black sea basin filling with salt water )and temporarily disrupt ocean salinity/temp/currents, one could easily imagine that massively increasing/decreasing precipitation/cloudiness , amount of surface water in lakes, causing huge effects on the other end of the continent, but going from there to proving causality of events happened in blinks of geological time scales. Uhm. Ok. Right. Hard to prove.

  33. Billy Liar says:

    As many commenters have noted; they never mention precipitation, the other way to shrink/expand a glacier.

    In the too difficult box perhaps?

  34. Billy Liar says:

    tty says:
    September 14, 2012 at 12:02 am

    We probably came quite close to a new Ice Age during the LIA.

    Now that would be an interesting modeling exercise – how close?

  35. Carsten Arnholm, Norway says:

    An example of a sudden expansion of a glacier is the well known Nigardsbreen (“nine farm glacier”) in Norway

    from http://bookmee.com/?p=10
    Around 1750 the so-called “little ice age” occurred in Jostedal. This concentrated surge of ice is a special feature of the Jostedal glacier, nowhere else in the world has there been reports of a similar natural phenomenon at that time. The ice destroyed cultivated land and farms as it surged forward. The saying has it that it that one glacier arm in Jostedal destroyed nine farms, therefore this arm has been named the “nine farm glacier” or Nigardsbreen in Norwegian (“breen” is glacier). During the “little ice age” the Nigard glacier grew around 100 meter a year.

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