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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Snowball Earth is also related to this discussion about shortwave radiation because the sun was around 30 percent dimmer around hundreds of millions of years ago. Therefore energy warming the Earth’s oceans and atmosphere from this would have been reduced back then. Hence, even if the same situation occured now they might never be a snowball Earth. Snowball Earth can be represented as a planet mainly covered by ice, not entirely covered which some are persuming. For example even a computer simulation (not evidence) shows above freezing around the equator.
http://en.wikipedia.org/wiki/File:SnowballSimulations.jpg
Brian H says:
May 30, 2011 at 7:16 pm
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.
The whole point of my posts on this is that this is simply not true.
Sorry it’s so tiresome for you, so perhaps you can understand how even more tiresome it is for me to see this untrue physics repeated ad nauseum by even more people on the net misdirected in their education, one of us is wrong. In fact, I was so disheartened to see you simply ignore what I’ve been saying on this, and the other couple of responses similar, that I seriously considered no longer bothering to reply to such or to ever mention it again. It was such a depressing thought that a whole generation in ‘western’ education has lost the knowledge we have gained in science, that this deliberate misdirection in education has eliminated real physics as surely as book banning and burning and mass murder of the educated did in Russia and China and Cambodia.
That’s why I call it AGWScience, not to be cute as someone thought, but because in it basic well-known facts about the properties of matter and processes have been deliberately changed in this ‘package’, and these changes have been repeated and repeated and taught and taught on every level of education for several decades that they are now taken as the norm, as if real scientific fact, when they are simply fabricated, and impossible in the real world.
In the real world, for the moment at least, those who actually produce stuff and still know how things work are around in sufficient numbers that we can still use real science knowledge from real engineers and such, the applied scientists, and benefit from their applications though they are routinely derided by AGWScience claiming the 2nd Law isn’t being violated for example, but perhaps if this misdirection becomes complete real science from which we get real progress will be made impossible for the masses, for any not in the ‘hierarchy’ which is manipulating this destruction of knowledge. So more insidious is the example of your post, and Matt G, that you have been educated to believe this fiction and so are aiding in spreading it to the detriment of the next generation. It’s only amusing for a while that the ‘skeptics’ who have been so thoroughly indoctrinated to believe these fictional claims are real science and even use them for their calculations and arguments against AGW. These AGWScience memes are viral.
Basic real world Science is that Light energies and Heat energies are different, they have different properties, they are different sizes for example and have different effects depending on the matter they encounter, did you take that in from the NASA page I’ve saved? The difference in size between the microscopic of Near Infrared and the pinhead size of Thermal Infrared? Don’t you think this might give some actual physical difference in encounters with other matter? Heat is an actual energy, Blue light is not hot, it has no heat energy. A massive amount of Heat energy can produce visible light, but that is only some one ten billioneth of the full spectrum of wavelengths produced by the Sun and these do not carry any Heat energy in their encounters with other matter, nor the invisible short wave Near IR and UV either side.
For example, UV is not hot, it does not heat the skin it ‘burns’, it acts by damaging the DNA and it takes melamine to transform those photons into benign heat. Overwhelmed by overexposure by skin unused to such we get sunburn. Luckily for us, UV is incapable of penetrating our bodies any further than the first layer of skin, the epidermis. Or we’d be in constant danger of getting sunburn all the way through our innards..
So in the AGWScience fiction of the KT97 Energy Budget, just how much is UV actually converting to heat the land and oceans of the Earth?
Visible light from the Sun is completely benign, it neither carries bigger Heat energy nor does it have the properties of UV, and the even shorter ionising wavelengths, to alter DNA to ‘burn’ our skin. Just how is it then capable of heating land and oceans as you say?
Visible light is tiny, it moves more quickly in the same length of space that thermal infrared moves, but it is light weight. It bounces off every molecule of oxygen and nitrogen it encounters, the scattering of light which gives us our blue sky as it reflects off these molecules. In these encounters then, the only effect is change of direction, there is no heat created. Water likewise with air is transparent to visible light, which is reflected off the molecules of oxygen in clear water to scatter randomly in all directions to give us blue seas. There is no heat exchange, there is no alteration in the molecules of water to ‘burn them’ as UV can burn skin, they are simply bounced away without alteration to their wavelength until they fade away.
Except for example when their energy is being used by the life forms in the oceans for chemical changes, which do not create heat, such as photosynthesis. 70% of all photosynthesis takes place in the oceans, the blue light’s energy used to create sugars as on land.
If blue light can’t heat a cup of water, then how can it heat an ocean of it? You say it’s because there is more light, but there is also more water.
Matt G – I’m not talking about what it takes to create visible light, but what effects visible light actually have. Converting visible light to electricity to heat a kettle is as you say impracticable because there isn’t enough of it, but that is not the direct heating of land and oceans claimed by AGWScience in their Energy Budget, KT97, which CLAIMS that Visible Light DIRECTLY converts to heat the land and oceans. As you see Matt has just claimed it heats the ocean.
So how does it do this?
The only energy from the Sun which can DIRECTLY heat land and oceans is Thermal Infrared.
And we have countless real world application to prove that Thermal Infrared heats matter, from room heaters to healing applications from penetration in bodies to raise temperature – thermal infrared heat pads for example.
AGWScience has so twisted and tweaked the properties of matter and energy to create a totally imaginary world of impossible workings. Even blatantly as Ira continues to say, that the heat we feel from the Sun is from these Solar energies – the opposite of what is true in real well-known physics, traditionally taught, as that NASA page gave; that the Heat WE FEEL FROM THE SUN, is Thermal Infrared.
While there are some who still remember, and still teach, traditional real world physics, using the knowledge in real world applications, any who claim AGWScience saying the opposite must prove traditional science wrong.
There are thousands of companies selling thermal infrared heaters to heat buildings, where are the thousands selling visible light heaters to heat buildings? If it can’t heat buildings how is it heating the land in the AGWScience claim?
Visible light can barely produce enough by first conversion to electricity to heat a tank of water, and yet the claim is that it DIRECTLY heats the oceans. Prove it. [There are Solar heating applications which use the direct energy of the Sun’s thermal infrared to heat water.]
If you can get your heads around the deliberate misdirection from AGWScience in the way it tweaks at giving properties of one thing to another, you’ll find it easier to spot how it does this with all its claims, for example giving Carbon Dioxide the physical properties of ideal gas, i.e. that it has none, and saying that this is how it acts in our real world atmosphere.
Remember the NASA page which no longer exists, but saved on web capture, that the heat we feel from the Sun is thermal infrared, this has been completely excluded from the AGWScience energy budget. That in itself shows the their energy budget isn’t real world science and so not to be taken as credible, not worth being skeptical about.., but their twisting of this to say that it is Light energies heating the Earth, giving them the properties of thermal infrared, is deliberate deviousness, to create ignorance.
Typo alert! melanin not melamine… 🙂 Seen any abdominal snowmen recently?
Myrrh;
Just an aside; doesn’t faze you AT ALL that no one, not one poster, agrees with you? Regardless of lack or depth of science background?
But I think your core misstatement above is that “blue light … has no heat energy”. Myrrh, ALL ENERGY is heat energy when it disperses and its entropy increases. That’s what thermodynamics is all about. That’s what the “Heat Death of the Universe” is all about.
There is NO energy that does not ultimately end up as heat.
And a blue laser will burn a hole in you just fine.
P.S. Try holding your hand next to a blue flame, the hottest kind. Or getting up close and personal with a blue star, likewise the hottest kind (with the exception of possible UV stars, which are hotter. Or X-ray pulsars, hotter still. Etc. )
What you are feeling is the heat of the object creating the visible light, not the blue light WHICH YOU CANNOT FEEL, which is an effect, coloured light, produced by the great heat you are feeling, which is Thermal IR. Just as an ordinary lightbulb gives of around 95% of the energy as heat, which is thermal IR, visible light only a small part of that.
There are countless real world applications created out of knowing the difference. Show me one real world application which uses blue visible light for heating.
Brian H,
http://wattsupwiththat.com/2011/05/30/skeptic-strategy-for-talking-about-global-warming/#comment-673382
For the different ways energy can be used which do not produce heat, and other posts. If you want to continue this discussion it would be better there as I’ve been objecting to Ira’s pushing of this AGWScience fiction meme.
Myrrh;
Your blue light ignorance stands on its own.
Red flames are around 1000K.
The hottest flame is blue (or a shade thereof), around 5000K.
In industrial processes, such as oxy-fuel welding and cutting, the base of the flame tends to be closer to the ultraviolet range. Frequencies in this range and higher are not considered “colored light”.
Pass your hand quickly over a red flame. No problem.
Pass your hand quickly over a blue flame. No hand.
And my point is, is it the flame or the thermal energy that is burning your hand? Light energies are not thermal, you cannot feel light as hot, but the heat that you’re feeling, that comes from the fire and burns your body if standing too close to it, is thermal infrared.
It is the heat that is creating the light.
The more thermal energy there is the higher frequency of light being emitted, but, the majority of the light emitted will be in the thermal infrared, this is what you feel as heat and that is what burns you. All the colour of the flame shows is how hot the source. The blue light emitted is an effect, not a cause of the heat.
Like an ordinary lightbulb, 95% of the energy created is heat, thermal infrared, which you cannot see but you can feel as heat. The 5% emitted as light is not heat. This is bog standard understanding in traditional physics, there are light energies and there are heat energies.
Thermal infrared, is heat on the move. From our Sun we get heat and light energies. Light energies are not hot. It’s the thermal energies which heat us and the land and the oceans.
Heat, thermal infrared, is powerful, it can be used to do work – like the internal combustion engine :
http://www.physicsclassroom.com/class/thermalP/u18l2a.cfm
AGWScience deliberately and maliciously confuses this point by overemphasising ‘high energy’ of visible light. This doesn’t equal power to do work, to heat things, to actually raise the temperature of something.
Read this page on light (http://www.physicsclassroom.com/Class/light/u12l2c.cfm) and note particularly what it says about transmission and reflection – blue light in the oceans is tranmitted through the water – it is not creating heat, it is not heating up the oceans, merely passing through.
Although note that it doesn’t mention chemical changes, this is what happens in photosynthesis where the energy is used to create sugars out of carbon dioxide and water, this is not a creation of heat. So light can become more light, can be used for a chemical change or heat.
O 4 X’s sake.
Higher frequency EM has more energy per wave, per anything you want to meter. That energy does stuff to whatever it impinges on. That something reduces, quickly or slowly, to mechanical agitation, or heat. There is no “blueness exception.”
Blue visible light is highly energetic, this does not therefore mean more powerful, it means only that it is travelling faster in the same distance (which means that since all light reaches us at the same time) the wavelengths are much much much much smaller, it doesn’t mean anything else.
These tiny wavelengths get bounced all over the sky by molecules of nitrogen and oxygen, that’s how we get a blue sky and blue oceans, the blue light is refected back at us and our eyes pick it up. Our eyes don’t get heated up by looking at the blue sky and sea.
UV is even more highly energetic than visible light, you can stop them by putting a shirt on. UV doesn’t have the power to get any further into your body than the FIRST layer of skin, (there are three layers), the epidermis. It doesn’t create heat when its energy gets into your skin, it doesn’t have the power to raise the temperature because its energy not powerful enough. It acts on the small DNA to change it, it’s melanin which the body produces as a defence mechanism against this, so you get a tan. If exposed to lots of it where it is intense, like high up on mountains, or unused to it, it can ‘burn’ you, but it’s not doing that by raising your temperature. Our bodies use UV in chemical changes, to create vitamin D, not to create heat. Do make the effort to read that page and take in how it requires a change of vibrational state to create heat, short wave do not have the power to raise this long enough or high enough or consistently enough to raise the temperature of something, they are too small and puny.
UV doesn’t penetrate organic matter to any depth because it is small and puny. It can act only smaller stuff like DNA but doesn’t have the power to move molecules of water into higher vibrational states to heat them up.
You’re confusing highly energetic with strong power because you’ve been brainwashed into thinking this. And it’s got to a point, because this is deliberately organised to play on the emotions of people to energise them into action to change how this is taught in schools, that real physics, the real knowledge we have gained so comparatively recently in our history, is being destroyed for the ‘masses’. Like book burning by totalitarian regimes everywhere creating ignorance by destroying the teachers and the educated of the next generations, like indoctrination and re-writing history.
Visible light is BENIGN. It is not hot either, is not thermal energy, it does not create heat because it is too puny to act that way with larger molecules of matter. It is not as energetic and larger than UV, it doesn’t mess with DNA to ‘burn’, as do also the other smaller more energetic wavelengths like gamma. It can penetrate skin a bit more than UV but it is then reflected back out at us, which is why we can see the world around us, because light is being reflected back at us, because it is not absorbed. That’s why you cast a shadow.
It is a ‘convention’ that light is described by the temperature of the source creating it, it is not the temperature of the wavelength. Wavelengths of light can create temperature in matter, the amount it can raise the vibrational energy state of the matter to create heat, but it takes thermal invisible light energies to be able to do that because they are more powerful.
In a nuclear explosions highly energetic shorter wavelength can vapourise matter completely, but that is due to the volume of it – in the space and time, the intensity. The burn victims of Hiroshima and Nagasaki where at a distance far enough for them not to be vapourised to nothing.
Myrrh, that post is so jam-packed with errors and misconceptions that I’m forced to award you an honorary Doctorate in Dontopedology.
Shrug. That’s the problem with AGWScience fed understanding, no concept of volume, size, any properties and processes, living in a one dimensional world where molecules don’t take up any space.
Speaking of understanding, did you study physics in junior high? Or even crack a textbook?