From the Institute of Physics , something so overreaching I just can’t believe the Institute of Physics would put out a press release on it. Where does one start with stuff like this? This is all modeling, they haven’t even tested any actual sea ice to see if it follows the theory. Their premise would be easy to test with some glacier water, a freezer, a controlled gaseous CO2 source, and a tensile/ductile strength mechanical force tester for brittleness. But that sort of basic testing wasn’t done. Yet, they equate their modeled posited effect to be the cause of the Pine Island Glacier breakoff, as if somehow events like that never happened before CO2 was at 392PPM. Note the abstract and link to the paper below. – Anthony
The well-documented presence of excessive levels of carbon dioxide (CO2) in our atmosphere is causing global temperatures to rise and glaciers and ice caps to melt.
New research, published today, 11 October, in IOP Publishing’s Journal of Physics D: Applied Physics, has shown that CO2 molecules may be having a more direct impact on the ice that covers our planet.
Researchers from the Massachusetts Institute for Technology have shown that the material strength and fracture toughness of ice are decreased significantly under increasing concentrations of CO2 molecules, making ice caps and glaciers more vulnerable to cracking and splitting into pieces, as was seen recently when a huge crack in the Pine Island Glacier in Antarctica spawned a glacier the size of Berlin.
Ice caps and glaciers cover seven per cent of the Earth—more than Europe and North America combined—and are responsible for reflecting 80 per cent of the Sun’s light rays that enter our atmosphere and maintain the Earth’s temperature. They are also a natural carbon sink, capturing a large amount of CO2.
“If ice caps and glaciers were to continue to crack and break into pieces, their surface area that is exposed to air would be significantly increased, which could lead to accelerated melting and much reduced coverage area on the Earth. The consequences of these changes remain to be explored by the experts, but they might contribute to changes of the global climate,” said lead author of the study Professor Markus Buehler.
Buehler, along with his student and co-author of the paper, Zhao Qin, used a series of atomistic-level computer simulations to analyse the dynamics of molecules to investigate the role of CO2 molecules in ice fracturing, and found that CO2 exposure causes ice to break more easily.
Notably, the decreased ice strength is not merely caused by material defects induced by CO2 bubbles, but rather by the fact that the strength of hydrogen bonds—the chemical bonds between water molecules in an ice crystal—is decreased under increasing concentrations of CO2. This is because the added CO2 competes with the water molecules connected in the ice crystal.
It was shown that CO2 molecules first adhere to the crack boundary of ice by forming a bond with the hydrogen atoms and then migrate through the ice in a flipping motion along the crack boundary towards the crack tip.
The CO2 molecules accumulate at the crack tip and constantly attack the water molecules by trying to bond to them. This leaves broken bonds behind and increases the brittleness of the ice on a macroscopic scale.
Carbon dioxide enhances fragility of ice crystals
Zhao Qin and Markus J Buehler 2012 J. Phys. D: Appl. Phys. 45 445302 doi:10.1088/0022-3727/45/44/445302
Abstract:
Ice caps and glaciers cover 7% of the Earth, greater than the land area of Europe and North America combined, and play an important role in global climate. The small-scale failure mechanisms of ice fracture, however, remain largely elusive. In particular, little understanding exists about how the presence and concentration of carbon dioxide molecules, a significant component in the atmosphere, affects the propensity of ice to fracture. Here we use atomic simulations with the first-principles based ReaxFF force field capable of describing the details of chemical reactions at the tip of a crack, applied to investigate the effects of the presence of carbon dioxide molecules on ice fracture. Our result shows that increasing concentrations of carbon dioxide molecules significantly decrease the fracture toughness of the ice crystal, making it more fragile. Using enhanced molecular sampling with metadynamics we reconstruct the free energy landscape in varied chemical microenvironments and find that carbon dioxide molecules affect the bonds between water molecules at the crack tip and decrease their strength by altering the dissociation energy of hydrogen bonds. In the context of glacier dynamics our findings may provide a novel viewpoint that could aid in understanding the breakdown and melting of glaciers, suggesting that the chemical composition of the atmosphere can be critical to mediate the large-scale motion of large volumes of ice.
Introduction
Ice caps and glaciers cover 7% of our planet, greater than the land area of Europe and North America combined [1]. They reflect 80–90% of the solar radiation and trap a large
amount of carbon dioxide. Specifically, the Arctic accounts for 10–15% of the earth’s carbon sink [2]. The glaciers’ dynamical behaviour and stability play important roles in controlling the global climate [3, 4]. Thereby, the facture mechanism of ice is of paramount importance for the understanding of glacial dynamics [5], and at a fundamental level is controlled by how a single crack propagates in ice crystals via the
breaking of chemical bonds [6]. Such growth of cracks eventually mediates the breakdown of ice, as exemplified in recent incidents of large-scale fracture of glaciers [7, 8]. Very
large-scale ice fractures occurred recently close to the Pine Island Glacier in the Antarctic region, which generated an iceberg with an area of around 880 square kilometres, the size
of the city of Berlin [9].
While the macroscopic mechanical properties of pure ice are well understood by laboratory tests and its behaviour has been characterized by existing fracture
mechanics models [10], the effect of environmental conditions such as the concentration of carbon dioxide, have not been incorporated into existing models. Lack of such knowledge prevents us from understanding how changes in the chemical environment affect the stability and movement of glaciers, which is important given the rising levels of carbon dioxide in the atmosphere.
[Suggestion: do some laboratory testing to get the same level of understanding]
…
Conclusion
Using atomic simulations with the ReaxFF reactive force field, we investigated the effect of carbon dioxide on the fracture behaviour of ice. We find that the material strength
and fracture toughness are decreased significantly under increasing concentrations of carbon dioxide molecules. This phenomenon is caused by the interaction between water and carbon dioxide molecules. Carbon dioxide molecules first adhere to the crack boundary by forming hydrogen bonds, and then migrate along the crack boundary towards the crack tip.
The dissociation energy of hydrogen bonds at the crack tip is decreased under the attack by carbon dioxide. This migrationattacking process repeats itself and renders the ice crystal more brittle by mediating crack propagation. Our theoretical model quantitatively accounts for the effect of carbon dioxide on the surface energy and fracture toughness of ice. It could be instrumental for further studies of ice fracture in various chemical environments and may be scaled up by incorporating it into models of glacier dynamics.
paper here (you may need to register for free account to read it)
http://iopscience.iop.org/0022-3727/45/44/445302/pdf/0022-3727_45_44_445302.pdf
Related articles
- S. African Scientist Kelvin Kemm: Glacier melting is not caused by global warning: ‘To melt ice, the temperature has to go up past 0 ºC to at least ‘plus something’ (climatedepot.com)
- Thwaites Glacier Tongue Major Calving Event, Antarctica (glacierchange.wordpress.com)
If this paper is correct, then it means break-up and subsequent loss of sea-ice is not as much of an indicator of global temperature as many of the CAGWists would have us believe.
Am I being incredibly stupid?
“Ice caps and glaciers cover seven per cent of the Earth—more than Europe and North America combined—and are responsible for reflecting 80 per cent of the Sun’s light rays that enter our atmosphere and maintain the Earth’s temperature. They are also a natural carbon sink, capturing a large amount of CO2.”
If the ice caps an glaciers cover only 7% of the earth’s surface how do they reflect 80% of the Sun’s light rays entering the earth’s atmosphere?
They talk about CO2 ‘bubbles’.
Just how does the 0.0004 percent CO2 fraction of the air get together to form bubbles?
IPCC ‘science’ requires the CO2 to be well mixed in the atmosphere.
But why let the facts spoil a good scare story!
I find this paper convincing. Clearly the increased levels of CO2 has caused quack propagation, both in ice, and in non-ice conditions. Especially the presence of CO2 near glaciers and other ice, such as the Antarctic, causes a great increase in quack propagation; beyond anything seen before. Is there really any doubt that the fantastic increase in quacking lately is caused by CO2?
(Do I really need a 😉 ….
doi:10.1088/0022-3727/45/44/445302
This link is broken.
First explain the Mpemba effect then we can say we understand water.
http://www.desy.de/user/projects/Physics/General/hot_water.html
Please. Does quacking bear any relationship to fracking? Oh I see…..
“Ice caps and glaciers cover seven per cent of the Earth—more than Europe and North America combined—and are responsible for reflecting 80 per cent of the Sun’s light rays that enter our atmosphere and maintain the Earth’s temperature” Bovine faeces yet again, as already pointed out here the angle of incoming solar radiation is too shallow at the poles, & six months of the year they are without sun pretty much.
Now, I have no figures for the flexural strength of ice but I have mentioned this previously, what they are talking about is a very simple & natural cantilever beam. All the signiticant force is at the support, (assuming the ice shelf to be fairly homogenous over time), in this case where the ice shelf abuts the larger mass of ice or land. The more the glacier spreads outwards over the seas, the more stress is applied to the supporting end, it is subjected to, by what are to all intents & purposes, uniformly distributed loads albeit dynamic being sea! It is bound to eventually break off under its own weight, & cracks always form at the least line of resistance. There is no mystery here & it would have little to do with any warming, it would crack under self-weight regardless once it reaches its flexural limits, which probably ain’t much to start with! Also the cracking could just as well be induced by flexural movement of the ice under movement of the seas beneath it, weakest point? Where it it supported,again!
E.M.Smith is correct about the increase in quacks:
“The U.S. Fish and Wildlife Service released its preliminary report on North American breeding ducks and habitat, and the population is about 48.6 million compared to 45.6 million last year.
That figure is also 43 percent above the 1955 to 2010 long-term average.
This year’s estimate is a record high, and only the sixth time in the survey’s history that the total duck population exceeded 40 million, according to the U.S. Fish and Wildlife Service.”
http://www.columbian.com/news/2012/aug/09/good-year-for-duck-hunters/
Sorry if this has already been said but if glaciers are more likely to crack now due to higher levels of atmospheric CO₂ doesn’t it follow that the chunks breaking off the end would be smaller and more numerous, rather than big pieces the ‘size of Berlin’. By the way, what is a Berlin in Wales or Manhattan equivalants?
“Specifically, the Arctic accounts for 10–15% of the earth’s carbon sink [2].”
This cannot be true. The CO2 mass in the atmosphere is 2,3 *10^15 kg, and in the oceans 141 *10^15 kg,
The ice volume in the Arctic is not near 10-15 % of the volume of the sum of all ocean water.
Not to consider all other carbon sinks, on land.
This paper gives me a Sokal feeling.
The reliance shown in model output is frightening. These ”scientists” need to get out more and actually run some experiments. Theories are all very well but if the observations do not follow the theory then the theory is WRONG.
It seems to me that their results are true at a molecular level. Throw a handful of CO2 molecules in with a few dozen ice crystals and the CO2 is going to compete to break up the H2O bonds.
So I suppose if amospheric concentrations of CO2 approached 200,000 ppm or so the glaciers would begin cracking like knees in a nursing home.
To get their basic research scaled up to a WAGTD level requires a LOT of ifs. I’m going to coin a term for that branch of climatology that can turn everything CO2 into a catastrophe. We can call it IFFYOLOGY.
Geoff Sherrington says:
October 10, 2012 at 10:35 pm
When was the last time you saw a paper authored by a plain Jones?
Was there one about UHI in China?
donald penman says:
October 10, 2012 at 8:54 pm
“http://en.wikipedia.org/wiki/Erich_von_D%C3%A4niken
I wonder how he would have fared today with his ideas if he got his papers peer reviewed.donald ”
Oh please. What an unfair comparison. Erich von Däniken never demanded tax payer money; and he never forced anyone to pay outrageous taxes or energy bills. Morally, he’s far above the slime that populates todays warmist institutions.
R. Shearer says:
October 10, 2012 at 6:52 pm
This could explain why ice core analysis for CO2 is biased low an underestimates historical CO2 levels.
Steve Short says:
October 10, 2012 at 7:03 pm
All that Pleistocene interglacial micro-cracking and hydrogen bonding must have simply allowed the CO2 to migrate away from the sites of maximal deposition.
Well, as far as I remember from the long past lessons in chemistry/physics, CO2 and other stuff migrates net from higher levels to lower levels, not reverse. Thus either the levels measured in ice cores were way lower in the past (lower than 180 ppmv during glacials, not really good for plants), or the migration is far less than what this study expected…
Anyway, Jaworowski was completely wrong on this point: if there are cracks in the ice cores, the CO2 levels inside the bubbles would increase over time with the current much higher CO2 levels in the atmosphere…
Last but not least, some very accurate methods sublimate all ice and separate all parts cryogenically, so that any hidden CO2 inbetween the ice crystals is captured too. The results of the “grating” technique, which only captures the airin the bubbles gives similar results, thus there is little CO2 hidden in the intercrystalline ice.
Bengt Abelsson says:
October 11, 2012 at 2:27 am
“Specifically, the Arctic accounts for 10–15% of the earth’s carbon sink [2].”
They (deliberately?) confuse between the Arctic as CO2 sink place by the Thermohaline Circulation (THC) and the amount of CO2 captured in ice. I once calculated how much CO2 is captured in all ice on earth. The enclosed air bubbles are some 3% of weight of the ice. With 180-300 ppmv CO2, that would give less than 1 ppmv in the atmosphere if all released at once, if I remember well…
Geoff.
You asked: “When was the last time you saw a paper authored by a plain Jones?”
You’d be surprised, there are loads of them. Name’s Jones; Phil Jones. Famous stirrer and shaker of temperature data.
H.R. says:
October 11, 2012 at 2:40 am
It seems to me that their results are true at a molecular level. Throw a handful of CO2 molecules in with a few dozen ice crystals and the CO2 is going to compete to break up the H2O bonds.
That highly depends of temperature. The main water like layer is at the boundary between ice and air, where the layer thickness is directly related to temperature, that can contain some CO2. At – 32°C, without salt/dust inclusions, there is no water like layer left at the surface (Vostok is average at -40°C…).
The layer between two ice crystals is of a different order: while not nicely ordered, it remains to be seen how much CO2 can be integrated, less how much still can migrate.
Further, CO2 as good as salts or any water soluble addition lowers the melting point of ice. Maybe it is that what the investigation is about?
And have a look at the opposite: put a bottle of Coke in the freezer: most of the bottle will freeze over, only leaving a small part of highly acidic liquid and near all CO2 in the above space. Be careful, it is not the first bottle that explodes, due to the high pressure buildup…
Ferdinand Engelbeen says:
October 11, 2012 at 3:37 am
My memory isn’t as good as it once was… If all CO2 from ice core was released at once, that would lower the CO2 levels of the atmosphere with less than 1 ppmv, because the CO2 levels in the ice cores air in average is a lot lower than in the current atmosphere…
Gunga Din says:
October 10, 2012 at 7:25 pm
Any chemist out there?
===========================================
I’m a chemist with publications in crystallography. The hypothesis of cracking glaciers with relatively minute increases in CO2 doesn’t seem plausible. It seems more likely that the physics of torque on the ice shelf is responsible. Glacier ice is not a near perfect crystalline structure. It is ice full of crystalline flaws, cracks, crevices and the like. The likely reason the crack formed was from torsional stress, not some heretofore unknown affect on hydrogen bonding by minute changes in CO2. But, like the authors, I have no experimental data to back up the hypothesis, just conjecture.
Just counting the minutes until this AGW scare story shows up in the Huffy Post and other prog fear-mongering sites.
Ferdinand Engelbeen says:
October 11, 2012 at 3:37 am
“My memory isn’t as good as it once was…”
That would be yours and Isabella I take it? Embalment will do that.
Its amazing the fracture strength of ice wouldn’t be incredibly well studied under a range of condition after all there is enormous money in potential Arctic development and ice breaking.
There is little doubt that this is part of a well-orchestrated, full-out assault on carbon dioxide. Left wing scientists from every conceivable field are now hypothesizing ways to demonize it. Willing governments and organizations are more than willing to fund the studies, so long as there’s a potentially bad outcome that points to CO2 as a culprit. Sorry to say, but this is the sad state of science in the world right now. I’m convinced that folks 100 or 200 years from now are going to look back on this time in history and give it a label such as The Era of Scientific Folly, or something similar.
These guys seriously believe that running a computer simulation is an experiment. What a pathetic epistemological heresy.