From Eurekalert: Caltech-led team debunks theory on end of ‘Snowball Earth’ ice age
Finds that rocks used as key geologic evidence were formed deep within Earth millions of years after the ice age ended
PASADENA, Calif.—There’s a theory about how the Marinoan ice age—also known as the “Snowball Earth” ice age because of its extreme low temperatures—came to an abrupt end some 600 million years ago. It has to do with large amounts of methane, a strong greenhouse gas, bubbling up through ocean sediments and from beneath the permafrost and heating the atmosphere.
The main physical evidence behind this theory has been samples of cap dolostone from south China, which were known to have a lot less of the carbon-13 isotope than is normally found in these types of carbonate rocks. (Dolostone is a type of sedimentary rock composed of the carbonate mineral, dolomite; it’s called cap dolostone when it overlies a glacial deposit.) The idea was that these rocks formed when Earth-warming methane bubbled up from below and was oxidized—”eaten”—by microbes, with its carbon wastes being incorporated into the dolostone, thereby leaving a signal of what had happened to end the ice age. The idea made sense, because methane also tends to be low in carbon-13; if carbon-13-depeleted methane had been made into rock, that rock would indeed also be low in carbon-13. But the idea was controversial, too, since there had been no previous isotopic evidence in carbonate rock of methane-munching microbes that early in Earth’s history.
And, as a team of scientists led by researchers from the California Institute of Technology (Caltech) report in this week’s issue of the journal Nature, it was also wrong—at least as far as the geologic evidence they looked at goes. Their testing shows that the rocks on which much of that ice-age-ending theory was based were formed millions of years after the ice age ended, and were formed at temperatures so high there could have been no living creatures associated with them.
“Our findings show that what happened in these rocks happened at very high temperatures, and abiologically,” says John Eiler, the Robert P. Sharp Professor of Geology and professor of geochemistry at Caltech, and one of the paper’s authors. “There is no evidence here that microbes ate methane as food. The story you see in this rock is not a story about ice ages.”
To tell the rocks’ story, the team used a technique Eiler developed at Caltech that looks at the way in which rare isotopes (like the carbon-13 in the dolostone) group, or “clump,” together in crystalline structures like bone or rock. This clumping, it turns out, is highly dependent upon the temperature of the immediate environment in which the crystals form. Hot temperatures mean less clumping; low temperatures mean more.
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  IMAGE: This is a view from one of the cap dolostone collection sites in south China, looking along the cliffs of the Yangtze Gorges.
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“The rocks that we analyzed for this study have been worked on before,” says Thomas Bristow, the paper’s first author and a former postdoc at Caltech who is now at NASA Ames Research Center, “but the unique advance available and developed at Caltech is the technique of using carbonate clumped-isotopic thermometry to study the temperature of crystallization of the samples. It was primarily this technique that brought new insights regarding the geological history of the rocks.”
What the team’s thermometer made very clear, says Eiler, is that “the carbon source was not oxidized and turned into carbonate at Earth’s surface. This was happening in a very hot hydrothermal environment, underground.”
In addition, he says, “We know it happened at least millions of years after the ice age ended, and probably tens of millions. Which means that whatever the source of carbon was, it wasn’t related to the end of the ice age.”
Since this rock had been the only carbon-isotopic evidence of a Precambrian methane seep, these findings bring up a number of questions—questions not just about how the Marinoan ice age ended, but about Earth’s budget of methane and the biogeochemistry of the ocean.
“The next stage of the research is to delve deeper into the question of why carbon-13-depleted carbonate rocks that formed at methane seeps seem to only be found during the later 400 million years of Earth history,” says John Grotzinger, the Fletcher Jones Professor of Geology at Caltech and the principal investigator on the work described. “It is an interesting fact of the geologic record that, despite a well-preserved record of carbonates beginning 3.5 billion years ago, the first 3 billion years of Earth history does not record evidence of methane oxidation. This is a curious absence. We think it might be linked to changes in ocean chemistry through time, but more work needs to be done to explore that.”
In addition to Bristow, Eiler, and Grotzinger, the other authors on the Nature paper, “A hydrothermal origin for isotopically anomalous cap dolostone cements from south China,” are Magali Bonifacie, a former Caltech postdoc now at the Institut de Physique du Globe de Paris, and Arkadiusz Derkowski from the Polish Academy of Sciences in Krakow.
The work was supported by an O. K. Earl Postdoctoral Fellowship, by the National Science Foundation’s Division of Earth Sciences and its Geobiology and Environmental Geochemistry program, and by CNRS-INSU (French research agency).
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Global ice ages had another important effect – or to put it another way, left an important legacy: soil. Moving ice sheets over land grinds the rock into soil. The Marinoan and Varangian ice ages (600-750 Mya) and also the Saharan-Andean (end of Ordovician) left layers of “weathered silicates” or in common parlance, soil. This set the stage for the evolution of land plants culminataing in trees and forests, which over the Silurian, Devonian and Carboniferous created the megaflora of forests that transformed the global climate, bringing down both temperatures and CO2 levels, and also promoting the hydrological cycle over land. Between them, the megaflora (and all plants globally) together with the hydrological cycle, created the robust stability that has characterised the climate over the Phanerozoic, and have allowed multicellular life to thrive for half a billion years. BTW the fluctuation of CO2 levels between 5000 and <1000 ppm over this period has no evident correlation with global temperature.
I made a couple of comments (with numbers so we were talking about actual science) at http://climateprogress.org/2011/05/19/arctic-sea-ice-volume-death-spiral/ (look to the end while it it still there) and even got two replies from Lewis C before he choked and cut the conversation very short. It seems that looking at melting permafrost in a chemically balanced, or one could say ecologically balanced way quickly inspires an ad hom response.
I analyse it as follows: they make a few statements, ‘Oh it is so terrible, and that Watts character is misleading people’. Then, you make some perhaps better informed comment with actual numbers showing that the alarmist position is perhaps overstated. You get a polite response the first time telling you to perhaps read a little – though Lewis did come back with a few cherry-picked numbers from one side of the equation (carbon emerging from the soil with a misrepresented CO2e value for CH4).
My second post showed that when real soil and trees and thawing permafrost are put together the result was a huge drawn-down in CO2 from the atmosphere when snowball earth (permafrost) ends.
Lewis C’s response was as follows: “The strength of your assurance that you know better than the many scientists who have studied this issue for decades plainly leaves no place for rational discussion.
“I’d suggest that you apply for a BSc degree with a reputable university – but you clearly already know all you need to know to proclaim science wrong.”
Well, he is right about his allowing no place for a rational discussion! Wow. Just to put a few things straight (as he closed the discussion after spitting on my shoe):
a) No one has studied this for decades, in fact the equipment for doing so has only been available recently and there is a good machine now from LiCor if you are interested. b) I was having a rational discussion and the problem was the conclusions were disturbing to Lewis C. c) I don’t want a BSc as nearly all universities would fail me for not repeating the ‘CO2-will-kill-us-all” meme. That is the gate-keeping that keeps the ‘industry’ alive. d) It is apparent from this very short interchange that I do indeed know enough to state someting factual about the issue and the facts oppose the alarmist stance. e) ‘The science’ that he says I claim to be ‘wrong’ is 1/2 science, not all. Science is balanced, like equations. That is why they are called ‘equations’. When discussing the emergence of CH4 from thawing permafrost, it is imperative to look the other obvious processes that are concurrent: plant growth, carbon sequestration, carbon emerging as CH4 and CO2, realistic timelines for decomposition and biomass accumulation and so on.
The permafrost alarmist position is like claiming gigantic gas mileage for a car when it goes downhill. Well, once you bring balance into the equation, the uphills, it becomes real science. What does down must come up.
SWR doesn’t heat the land and oceans does it? It’s just more junk science like “CO2 traps heat”.
Smokey replied to someone claiming that CO2 traps heat, to look around his house, did he have any appliances which worked by CO2 trapping heat. Same here, I look around my house and I don’t have anything that cooks my food or heats my bath water with Visible Light.
AGWScience is a science all to itself. It makes proposterous claims about the basic properties and processes of stuff in our real physical world and creates a totally imaginary world.
Anyway, that aside, from the posts here and some trawling about dolomite, all very confusing as its called that in its crystal form too, I think I’ve got this right: dolomite the rock is merely limestone with added magnesium, which replaces some of the calcium and creates dolomite, so it doesn’t take heat and has nothing to do with methane?
Limestone is critter shells compressed, but how then does the dolomite form in that? Someone said seas are rich in magnesium so this could be going on all the time? How then are there large distinct amounts of it separate from limestone?
This also says that limestone can form direct in seas, (http://www.mountainnature.com/geology/Deposition.htm), but again, how does some only react with magnesium to form distinct dolomite?
Also, found this: http://www.whoi.edu/page.do?pid=10519&cid=22611&c=2
Iridium found in concentration amounts in basal layers of cap dolomite formations overlying glacial sediments deposited during Snowball Earth and earlier Sturtian glaciations, says lends credibility to hard Snowball and not slushy.
Mr. Watts.
I’ve been wondering lately about the correlation between the loss of Mars atmosphere and the first snowball earth.
I would like to find out if it’s possible the cause of snowball earth was because it was hit a gamma ray burst that burned off most of the atmosphere around the same time mars lost its atmosphere.
If this was the case the Ice would not have been covered in snow, it would have been Ice Cube (lol) earth.
I’ve lived in the Yukon and it is very common for Ice puddles to simply vaporize when it is sunny and well below freezing. Could this not be how our atmosphere began to recover and in turn held heat to begin ice melt?
“Jeremy says:
May 25, 2011 at 6:56 pm
Henrik Svensmark’s GCR theory explains all of this quite adequately. Read the book: The Chilling Stars.”
Exactly! The snowball Earth events co-incide nicely with the passage of our solar system through the thick part of the galactic arms. Therefore, extra Cosmic rays penetrate the atmosphere, seeding more low clouds thereby increasing the Albedo of the Earth, reflecting more sunlight back into space, and hence we get a global super ice age.
The end of the snowball earth occurred as our solar system left the galactic arm.
mod; I immediately figgered out GTFA from context, but tried to find it in accepted acronyms, even the Urban Dictionary. No joy. So you invented a self-explanatory Acronym, the best kind!
‘Grats and Kudos.
[Reply: I was having a bad day and I regret my unprofessional response, even after Villabolo (G. Hernandez) posted under another fake screen name for the third time. ~dbs, mod.]
A sublime theory!
😉
Is Svensmark’s then based on, or the same as, Pavlov et al (2005)? : http://www.snowballearth.org/news.html
Scroll down to: “Astonomical origin for snowball earths?”
While the blurb for the Chilling Stars just says its the Sun playing cricket/baseball with the cosmic rays. http://www.amazon.com/Chilling-Stars-Theory-Climate-Change/dp/1840468157
Re the abundance of CaCO3 – this looks to be a halfway stage in creating Dolomite: http://www.galleries.com/minerals/carbonat/dolomite/dolomite.htm
Dolomite differs from calcite from the addition of magnesium ions.
So is what should be looked for after the ‘Snowball’ Earth, a rapid/prolonged addition of magnesium from some source in the warming waters?
Popcorn rocks! http://www.teachersource.com/Images/UserDir/RM-375.html
Dolomite doesn’t need high temps to form, does it? So, could they have been measuring the ‘heat’ from something else rather than dolomite formation? Just asking.
http://www.wisconsingeologicalsurvey.org/rockelm.html
Something like that?
I have never accepted the snowball earth conjecture. As I have posted several times on WUWT over the past year, Prof Richard Lindzen has stated:
“There is ample evidence that the Earth’s temperature as measured at the equator has remained within +/- 1°C for more than the past billion years. Those temperatures have not changed over the past century.”
I trust that Dr Lindzen would not make that statement without plenty of corroborating evidence. Thus, the idea that the planet was a “snowball” or an “iceball” in the past was merely conjecture. And as the article shows, it is now a falsified conjecture.
kadaka,
Thanks for the Science Daily link. I especially enjoyed their “What is Astral Projection” link. That fits in perfectly with SciDaily, IMHO – not much different than New Scientist.
Myrrh says:
May 26, 2011 at 8:17 pm
Hi myrrh,
Shortwave radiation from solar energy does heat the land and the ocean. Just that land loses heats far quicker than water does and penetrates much further down to 100m with latter. The UHI affect is just caused by this energy heating the concrete surface and slowly emitting during the night period. This is just one of the reasons why cities have much warmer temperatures than the countryside.
This give an idea how short and long wave radiation affect the planet.
http://earthobservatory.nasa.gov/Experiments/PlanetEarthScience/GlobalWarming/GW_Movie1.php
If you are still unsure just look at the surface ocean temperatures where the difference between the poles and the tropics is increasing solar energy penetration from the sun.
http://weather.unisys.com/archive/sst/sst-110522.gif
A simple experiment to confirm this can be done by anyone. Shortwave radiation in the sun does warm a cup of water and in fact easily warms a large bowl of water during the day. Try this yourself by comparing two containers of the same type and volume, both outside. Place one in the shade all day and the other exposed to the sun. Measure both temperatures and compare the difference. The volume of water must be same for both and just use it from a cold water tap. The one in the sun rises greatly just during one day. (about 20c difference bewteen the two – using container of about 3 litres)
Matt G – Short Wave Radiation, “Solar” of the AGWScience KT97 Energy Budget v Thermal IR.
In other words, this does not include Thermal IR, which is in play in your descriptions.
How does, say, Blue Visible Light heat water and land?
Myrrh says:
May 29, 2011 at 9:54 am
“Matt G – Short Wave Radiation, “Solar” of the AGWScience KT97 Energy Budget v Thermal IR.
In other words, this does not include Thermal IR, which is in play in your descriptions.
How does, say, Blue Visible Light heat water and land?”
I refer to all shortwave radiation with infrared having less influence overall. Shortwave radiation represents any type of small wave length including visible that overlaps infrared a little, but still counts as relatively short wavelengths. While many people attribute all radiant heating to infrared light and/or all infrared radiation to heating.
This is a widespread misconception, since light and electromagnetic waves of any frequency will heat surfaces that absorb them. Infrared light from the Sun only accounts for the minority of the heating of the Earth, with the rest being caused by visible light that is absorbed then re-radiated at longer wavelengths. So to answer your quesion visible light behaves very similar to infrared except it penetrates water deeper. Well done for spotting what seemed shortwaves = infrared only.
Matt G – Shortwave Infrared is not thermal.
May I ask when you were taught this?
Matt G – AGWScience is a corruption of real traditional science. It takes basic well-known, well-tested, used in countless applications basics in the real world, and twists them ever so cleverly. Sometimes as here, simply by making a statement that Solar SWR heats the Earth, most don’t ever check, it’s become so prevalent, that is the opposite of what are the true properties of the wavelengths. But as you note, some still say this isn’t true, that it’s not traditional well-known, well-tested, etc., so, we’re still in the middle of this brainwashing, deliberate, it can’t be anything but deliberate, to create an extremely ignorant generation, and by and large they’ve succeeded because this has been introduced into the school system. No need to burn books, just teach a new science and confuse the masses, including scientists in other disciplines who will take such planned misdirection as if fact.
But it’s fiction. AGWScience is ScienceFiction, completely made up.
I’m not going to continue discussing it with you at the moment, I’ve just had a rather long stint of doing that elsewhere, but here’s one page of traditional science you might like to think about.
http://science.hq.nasa.gov/kids/imagers/ems/infrared.html
Saved on: http://www.webcitation.org/5y68eeRD
The Short Wave Radiation of Visible Light is not thermal, it is not the heat we feel from the Sun. The Heat from the Sun is Thermal Infrared, it is what heats the water and land, it is the heat we feel from the Sun that actually warms us. Visible Light can’t do that.
Try heating water with Visible Light to make your coffee. Don’t bother giving me descriptions of ‘how it does it’, I’ve heard them all, show it works. Put it to the Smokey test and look around your house first, and then look for proof that it can in any way you like. [Hint, just because, say, Blue Visible Light penetrates deeper in the ocean, doesn’t mean it’s creating heat while doing so.]
Remember, what you have to prove is that these SWR, (UV, Visible and Near IR) convert to heat the land and oceans to raise the temperature of the Earth globally, from which the hot Earth then radiates out the Thermal IR claimed in the AGWScience’s Energy Budget.
Good luck.
Myrrh says:
May 29, 2011 at 1:45 pm
I don’t include most of MWIR (thermal) and none of LWIR (thermal) because it doesn’t penetrate the skin surface of water and can be classed as longwave. Shortwave radiation has never been meant to be thermal IR in my descriptions. These include skin layer mentioned, with longwave radiation that thermal IR mainly comes into. To be clear by shortwave from the sun, it represents a range of total energy from 0 – 4μm. This includes for example visible, uv and infrared (but only part of it)
Seems to me the paper talks only about the dolomites in south China, not about cap dolomites in general. Most of the cap carbonates I know of have distinctive sedimentological features that indicate they formed as surface deposits, not in a “very hot hydrothermal environment, underground”.
I did my undergrad mapping in the Flinders Ranges, South Australia, where the Nuccaleena Formation is the cap carbonate immediately, and probably conformably (i.e. no break in the stratigraphic record) overlying the Elatina Formation, which often contains characteristic glacial sediment facies; none of the formations overlying the Nuccaleena has any glacial features. The interpretation of the Nuccaleena for several decades at least was that it was abiogenically formed from carbonate precipitating out of the sea water in the super-greenhouse that immediately followed the super-icehouse of the Cryogenian (no talk about methanotrophs and clathrates). This was probably partly caused by CO2 having built up to gigantic levels due to volcanic outgassing in the absence of significant weathering, before its heating effect was able to overcome the albedo effect of the huge ice sheets; so when the ice was gone and the climate got very hot, very quickly, the ocean chemistry changed abruptly and the carbonate precipitated out very quickly. The paper has nothing to say against this hypothesis.
Crispin in Waterloo: you can’t compare today’s permafrost with that of Snowball Earth, as terrestrial plants and soil as we know it were still several 100 million years off.
Matt G – the claim is that Non-Thermal converts to heat the Earth, land and sea, I understand what you’re saying… The IR included in AGWScience’s energy budget is problematic, billed as Near IR, it is into Mid which is thermal. Taking the two shortwaves away either side, UV and IR, prove that Visible Light heats the oceans and land. Just try with Blue Light, since the claim is that this heats the oceans because it goes down furthest. I won’t hold my breath waiting for an answer.
………….
I couldn’t find any details of their actual study, only the announcement of it. How does cap dolomite differ from any other?
Clear and useful analysis, Mr. Eschenbach — for those who are inclined to analyze.
But tell me this:
Would any analysis, criticism, logical argument or factual evidence help to persuade and bring around those who firmly believe in their irrational ideology, sacred book or mock-scientific dogma? Or those who derive their livelihood from these lies?
My point is, our most important and immediate task is to find effective practical ways and means — financial, organizational, and legal — to overcome the nascent green faith, to deprive it of political support, to take away its access to public funds, and — which is absolutely necessary! — to see that the most active fraudsters stand trial and go to jail.
Scientific bankruptcy of the green scaremongering is obvious not only to us but to its preachers themselves. The most influential priests of “man-made climate change” scare are smiling when they see us debunking their swindle in our blogs. While we are at it, they do the real thing, making political connections, finding rich sponsors, controlling professional and mainstream magazines and associations, dominating in academic institutions and international organizations, incessantly brainwashing the masses with total impunity.
They have money and power. We have none. Money and power are what we need to extinguish this poisonous source of lies before the whole world becomes one faceless, Chinese-style dictatorship spewing pious propaganda, gagging all dissidents, and keeping the large minority of working people under control by feeding products of their ingenuity and labor to the majority of parasites.
In essence, to fight off green lies, we must radically change the structure of democracy. In its present form, there will be soon no real difference between what we call “democracy” in the United States, and what they mean by “democracy” in Syria, Russia, and China.
You often make good posts, but this inane misunderstanding of yours got real old and tiresome long ago.
The blue light penetrates furthest because it takes that much water to stop it. So a flask-full would only intercept a little. But in deep water all of it turns into heat. Which is the whole point.
Myrrh says:
May 29, 2011 at 11:12 pm
All of CAGW science is made up or assumptions, but this is definetly not one of them. It is impossible to create visible light without energy. All chemical reactions that create visible light give off heat. There are many examples that prove this from candles, bulbs, tv’s, LCD’s and nuclear fission. Can make enough light at once to vaporise a entire swimming pool, nevermind warm it to make coffee. A kettle could easily be converted to a 2KW visible light source to heat water, just that it’s not practical because the source is limited.
http://en.wikipedia.org/wiki/Light