Claim: Formation of coal almost turned our planet into a snowball

From the POTSDAM INSTITUTE FOR CLIMATE IMPACT RESEARCH (PIK) and the “take what PIK says wth a heavy dose of salt” department. On the plus side, if true, this means that burning coal will prevent a global glaciation.

Formation of coal almost turned our planet into a snowball

About 700 million years ago, runaway glaciers covered the entire planet in ice. Harvard researchers modeled the conditions that may have led to this so-called ‘snowball Earth’.
CREDIT (Image courtesy of NASA)

While burning coal today causes Earth to overheat, about 300 million years ago the formation of that same coal brought our planet close to global glaciation. For the first time, scientists show the massive effect in a study to be published in the renowned Proceedings of the US Academy of Sciences. When trees in vast forests died during a time called the Carboniferous and the Permian, the carbon dioxide (CO2) they took up from the atmosphere while growing got buried; the plants’ debris over time formed most of the coal that today is used as fossil fuel. Consequently, the CO2 concentration in the atmosphere sank drastically and Earth cooled down to a degree it narrowly escaped what scientists call a ‘snowball state’.

“It is quite an irony that forming the coal that today is a major factor for dangerous global warming once almost lead to global glaciation,” says author Georg Feulner from the Potsdam Institute for Climate Impact Research. “However, this illustrates the enormous dimension of the coal issue. The amount of CO2 stored in Earth’s coal reserves was once big enough to push our climate out of balance. When released by burning the coal, the CO2 is again destabilizing the Earth system.”

The study examines the sensitivity of the climate in a specific period of Earth’s deep past by using a large ensemble of computer simulations. While some of the changes in temperature at that time can clearly be attributed to how our planet’s axis was tilted and the way it circled the sun, the study reveals the substantial influence of CO2 concentrations. Estimates based on ancient soils and fossil leaves show that they fluctuated widely and at some point sank to about 100 parts CO2 per million parts of all gases in the atmosphere, and possibly even lower. The model simulations now reveal that global glaciation occurs below 40 parts per million.

Burning that same coal dangerously raises greenhouse gas concentration in our atmosphere

Today, CO2 levels in the atmosphere have reached more than 400 parts per million. Carbon dioxide acts as a greenhouse gas: the Sun warms Earth’s surface, but most of the heat radiated by the surface escapes into space; CO2 and other greenhouse gases hinder part of this heat from escaping, hence warming the planet.

“We should definitely keep CO2 levels in the atmosphere below 450 parts per million to keep our climate stable, and ideally much lower than that. Raising the amount of greenhouse gases beyond that limit means pushing ourselves out of the safe operating space of Earth,” says Feulner. “Earth’s past teaches us that periods of rapid warming were often associated with mass extinction events. This shows that a stable climate is something to appreciate and protect.”

###

Article: Feulner, G. (2017): Formation of most of our coal brought Earth close to global glaciation. Proceedings of the National Academy of Sciences (PNAS)

http://www.pnas.org/content/early/2017/10/03/1712062114.abstract

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October 9, 2017 4:38 pm

Except coal doesnt all come from just those two periods.

Bill Illis
Reply to  J. Richard Wakefield
October 9, 2017 4:55 pm

There was Zero coal formed in the Snowball periods, before or after or during or at the end of. Must be very difficult for a climate scientist to understand what Zero means.

sunsettommy
Reply to  Bill Illis
October 9, 2017 8:59 pm

Even funnier when the CO2 level was still much higher than today.

Bryan A
Reply to  Bill Illis
October 9, 2017 10:11 pm

When CO2 was much higher than today…life flourished

“It is quite an irony that forming the coal that today is a major factor for dangerous global warming maintaining Earth’s temperature once almost lead to global glaciation,” says author Georg Feulner from the Potsdam Institute for Climate Impact Research. “However, this illustrates the enormous dimension of the coal issue. The amount of CO2 stored in Earth’s coal reserves was once big enough to push our climate out of balance. When released by burning the coal, the CO2 is again destabilizing the Earth system.”

For the CO2 to have destabilized the climate, the stable climate should be snowball earth, CO2 would be <80ppm and life would be nonexistent.
For life to thrive, CO2 needs to be above 350ppm.
Seems like the report has it Bass Ackwards

rocketscientist
Reply to  Bill Illis
October 10, 2017 8:00 am

To an alarmist, zero, is the value of his credibility.

Urederra
Reply to  Bill Illis
October 10, 2017 8:50 am

They make up what zero means. Same as they made up what hole means in the term “ozone hole” or what essentially ice free means when they talk about “essentially ice free Arctic”.
Hint: essentially ice free means less than 1 million square kilometres. FYI the area of the state of Texas is 695,662 km². Less than 1 million km²

Steven F
Reply to  Bill Illis
October 11, 2017 1:08 pm

The evidence of snowball earth occured 700 million years ago. Plants didn’t exist at that time. Only Algae in the ocean. Very different condition than when coal was formed.

Reply to  Bill Illis
October 11, 2017 10:00 pm

700 million years ago is well beyond our ability to measure anything from that time.
Potscam Institute
lmao

Dean
Reply to  J. Richard Wakefield
October 9, 2017 5:06 pm

And a lot of it comes from after the glaciation…

Marysduby
Reply to  J. Richard Wakefield
October 10, 2017 5:58 am

Henry Fountain reports via The New York Times (Warning: source may be paywalled; alternative source):
The Arctic is warming about twice as fast as other parts of the planet, and even here in sub-Arctic Alaska the rate of warming is high. Sea ice and wildlife habitat are disappearing; higher sea levels threaten coastal native villages. But to the scientists from Woods Hole Research Center who have come here to study the effects of climate change, the most urgent is the fate of permafrost, the always-frozen ground that underlies much of the state. Starting just a few feet below the surface and extending tens or even hundreds of feet down, it contains vast amounts of carbon in organic matter — plants that took carbon dioxide from the atmosphere centuries ago, died and froze before they could decompose. Worldwide, permafrost is thought to contain about twice as much carbon as is currently in the atmosphere. Once this ancient organic material thaws, microbes convert some of it to carbon dioxide and methane, which can flow into the atmosphere and cause even more warming. Scientists have estimated that the process of permafrost thawing could contribute as much as 1.7 degrees Fahrenheit to global warming over the next several centuries, independent of what society does to reduce emissions from burning fossil fuels and other activities. In Alaska, nowhere is permafrost more vulnerable than here, 350 miles south of the Arctic Circle, in a vast, largely treeless landscape formed from sediment brought down by two of the state’s biggest rivers, the Yukon and the Kuskokwim. Temperatures three feet down into the frozen ground are less than half a degree below freezing. This area could lose much of its permafrost by midcentury.
https://science.slashdot.org/story/17/08/25/2124203/alaskas-permafrost-is-thawing

MarkW
Reply to  Marysduby
October 10, 2017 6:26 am

And it still wouldn’t be enough to get CO2 levels back to the levels they were when the earth almost froze over.

October 9, 2017 4:44 pm

Keep on burning that coal so that we can escape a dreaded Snowball earth, which we know that you would not like.

higley7
Reply to  ntesdorf
October 9, 2017 7:04 pm

These “scientists” completely ignore the Beer-Lambert Law, in which, if CO2 had any detectable effect, its main contribution would have been with the first 20–40 ppm. As the effect plateaus, its ability to have any effect has gone to inconsequential. They seem to think CO2’s effects are HUGE and linear. Stupid.
They also ignore the fact that water vapor is up to 40,000 ppm and is 20 times the radiative gas that CO2 is. It beggars the imagination that these purported scientists are willing to claim that our climate history if dominated by CO2 in the atmosphere. How stupid are they? Well, I guess they are trying to show us.
Better yet, they probably assume that water vapor magnifies the effects of CO2. First, have they ever looked at CO2’s absorption spectrum? It looks like a picket fence with only two pickets in it, with most IR radiation transparent to it. Water vapor does better but only on one side of the IR range and it overlaps with one of CO2’s pickets, thus these two gases interfere with each other.
One effect these atmospheric brains do not recognize is that, as CO2 rises, the absolute water vapor concentration in the atmosphere decreases, such that, since water vapor is the superior radiative gas, the result of increased CO2 would be global cooling through decreased water vapor..
Regardless, what they also ignore is that water vapor makes air less dense and warm, and humid air rises as part of the water cycle, carrying heat energy as well as the latent heat of evaporated water (insensible heat) to altitude where the heat is lost to space as the water condenses and rains back to the surface.
This water cycle is a huge global heat engine that moves roughly 85% of the planet’s solar energy budget. This is Trenberth’s missing energy, which he pretends is “lurking” in the deep ocean, waiting to jump out of the closet in the future (really, that their level of thinking). The warmist climate models do not use the water cycle, considering, myopically, that water vapor is commanded by CO2, it’s slave. And, if the climate does warm, this engine ramps up to bring the temperature back down. What changes the climate is changes in the solar input and the solar wind/cosmic wind balance.

Reply to  higley7
October 10, 2017 4:49 am

Nice summary!

Reply to  higley7
October 10, 2017 5:17 am
Samuel C Cogar
Reply to  higley7
October 10, 2017 6:10 am

A response to Higley7 ….. “These “scientists” completely ignore the ……
Excerpted from above article:

“It is quite an irony that forming the coal that today is a major factor for dangerous global warming once almost lead to global glaciation,” says author Georg Feulner from the Potsdam Institute for Climate Impact Research.

And just how many “global glaciations” occurred as a result of the atmospheric CO2 “ingassing” that resulted in the formation of all the different forms of calcium carbonate (CaCO3) that are now sequestered as part of the earth’s solid surface, …… given the fact that said quantity of sequestered calcium carbonate is probably 10 to 15 times greater than the quantity of sequestered coal?
To wit:

Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks as the minerals calcite and aragonite (most notably as limestone, which contains both of those minerals) and is the main component of pearls and the shells of marine organisms, snails, and eggs.

Jan Christoffersen
Reply to  higley7
October 10, 2017 8:39 am

Samuel S. Cogar,
“… sequestered calcium carbonate is probably 10 to 15 times greater than the quantity of sequestered coal.”
No, that figure is a gross underestimation. Sequestered calcium carbonate is likely 10,000 times greater than the quantity of sequestered coal. Think of the enormous tonnages (untold trillions upon trillions) of CaCO3 deposited in huge carbonate basins around the world. Coal deposits are trivial in comparison.

Wim Röst
Reply to  higley7
October 10, 2017 10:25 am

Higley7, I am interested in how you came to your statement: “water vapor is up to 40,000 ppm and is 20 times the radiative gas that CO2 is”. How did you get to that number ’20’?
I was searching for the Global Warming Factor (GWF) of water vapour, but although the IPCC admits that water vapour is the most abundant greenhouse gas, they ‘forgot’ to mention the GWF of water vapour while mentioning the GWF of all kinds of trace gases…. (At least, I could not find such a number)

DD More
Reply to  higley7
October 10, 2017 3:30 pm

Sam C Cogar – “probably 10 to 15 times greater”
Dr Patrick Moore had the number just a bit larger than that.
Today, at just over 400 ppm CO2 there are 850 billion tons of CO2 in the atmosphere. By comparison, when modern life-forms evolved over 500 million years ago there was nearly 15,000 billion tons of CO2 in the atmosphere, 17 times today’s level. Fossil fuels, which were made from plants that pulled CO2 from the atmosphere account for 5,000 – 10,000 billion tons of carbon, 6 – 12 times as much carbon as is in the atmosphere.
But the truly stunning number is the amount of carbon that has been sequestered from the atmosphere and turned into carbonaceous rocks. 100,000,000 billion tons, that’s one quadrillion tons of carbon, have been turned into stone by marine species that learned to make armour-plating for themselves by combining calcium and carbon into calcium carbonate.

https://wattsupwiththat.com/2015/10/15/greenpeace-founder-delivers-powerful-annual-lecture-praises-carbon-dioxide-full-text/comment-page-1/
100,000,000 / 10,000 = 10,000 x’s more.
The model simulations now reveal that global glaciation occurs below 40 parts per million.
No, CO2 always FOLLOWS Temperature – So, now reveal that below 40 parts per million occurs only during global glaciation.

Samuel C Cogar
Reply to  higley7
October 11, 2017 5:01 am

@ Jan Christoffersen and DD More ….
I knew that about the massive amounts of sequestered CaCO3 but didn’t know the actual estimations ….. so I just stated a CMA of 10/15X greater ……. which was for the benefit of the science illiterates.

ricksanchez769
October 9, 2017 4:47 pm

“Burning that same coal dangerously raises greenhouse gas concentration in our atmosphere”…now only if there was some evidence to substantiate this claim.

TA
Reply to  ricksanchez769
October 9, 2017 4:59 pm

There is no evidence that CO2 heats the Earth’s atmosphere and there is no evidece that CO2 cools the Earth’s atmosphere.
This is all pure speculation.

The Reverend Badger
Reply to  TA
October 10, 2017 12:03 am

The meercat of CO2 = SIMPLES.
Yes, TA, we like it . Can you suggest any kind of experiment or observation we can do which will either confirm or deny the veracity of your statement?
We should get working on spending a modest amount, say $100 million, on testing this statement. If it turns out to be true we will have literally saved the Earth. If it turns out to be false we will maybe have quantified the effect.

Richard Bell
Reply to  TA
October 10, 2017 10:52 am

The effect has been measured and the measured effect is small. The radiative forcing from CO2 went up at 0.2 watt per square meter per decade while CO2 was rising at 22 ppm per decade.
The positive feedback mechanisms that they claim turn that small radiative forcing into the main driver of climate change is the missing and undefined affects that are assumed in AGW, but for which there is no evidence.
http://newscenter.lbl.gov/2015/02/25/co2-greenhouse-effect-increase/

Lars P.
Reply to  TA
October 10, 2017 2:28 pm

Richard Bell says:
October 10, 2017 at 10:52 am
The effect has been measured and the measured effect is small. The radiative forcing from CO2 went up at 0.2 watt per square meter per decade while CO2 was rising at 22 ppm per decade.
I find this study a bit strange. Let me explain why:
1) “The scientists measured atmospheric carbon dioxide’s contribution to radiative forcing at two sites, one in Oklahoma and one on the North Slope of Alaska, from 2000 to the end of 2010”
I think this is a very short time period with very small CO2 variation. Do we talk of 390 ppm to 400 ppm?
2) It is nowhere stated that the average air/soil temperature was constant or measured in this period.
If the ground was warmer in 2010 then in 2000, the increase in temperature results in an increase in infrared radiation from the ground towards the air and from the warmer air towards the ground.
Did they measured the increased radiation of the warmer air and attributed it to radiative forcing?
The path through the air (transparency) of the CO2 frequency radiation is about 10 – 20 meters (if I correctly remember)
So what was the temperature of the air in 10-20 meters height during all these measurements? I fail to see that they accounted for that.

kokoda - AZEK (Deck Boards) doesn't stand behind its product
Reply to  ricksanchez769
October 9, 2017 5:03 pm

Same with “While burning coal today causes Earth to overheat…” – I couldn’t read past this BS.

Yep! Especially when you think of the Holocene optimum, when it was much warmer than today, without burning fossil fuels.

AndyE
Reply to  ricksanchez769
October 9, 2017 6:52 pm

Well yes, the evidence is there – but based on a computer programme. That same computer evidence is, of course, the basis for this present research result. The problem is : We observe climate changes, and assume we know the reason for all climate changes, namely atmospheric CO2 – and proceed to put that theory into the computers as if it were a fact. These computer wizards must learn to differentiate between facts and theories.

J Mac
Reply to  AndyE
October 9, 2017 10:35 pm

AndyE,
None of those ‘computer programmes’ have been calibrated or certified as having any predictive capabilities as relates to climate changes. That isn’t ‘evidence’. It is baseless conjecture!

leopoldo Perdomo
Reply to  AndyE
October 10, 2017 4:58 am

between facts and false theories.

Bill Illis
October 9, 2017 4:49 pm

The Snowball periods happen when 60% or so of the continents are connected together in a land mass centered over one of the poles. Think Antarctica times 10 or times 20. Each Antarctica drops Earth temperature by 2.0C just by the amount of solar energy reflected back to space versus not having an Antarctica. Make that 10 of them and yeah, you get a Snowball. Continental drift breaks up this alignment and moves the continents away from the pole and the Earth is much warmer. The math says +/- 40C from this impact alone.

Roger Knights
Reply to  Bill Illis
October 9, 2017 5:37 pm

Why didn’t a peer reviewer point this out? Tsk, tsk.

Jeanparisot
Reply to  Roger Knights
October 9, 2017 6:00 pm

I don’t believe the “renowned Proceedings of the US Academy of Sciences” is peer reviewed.

Gary
Reply to  Roger Knights
October 9, 2017 6:39 pm

Why didn’t a peer reviewer point this out?
Common blindness, perhaps. Or maybe something less innocent…
Merriam-Webster definition of peer: One that is of equal standing with another; equal; one belonging to the same societal group especially based on age, grade, or status.

tty
Reply to  Roger Knights
October 10, 2017 12:59 am

“I don’t believe the “renowned Proceedings of the US Academy of Sciences” is peer reviewed.”
It is supposed to be at least for non-members of the Academy.

Willy Pete
October 9, 2017 4:53 pm

CO2 dropped during the Carboniferous Period because earth cooled. Lowering CO2 didn’t cause the Carboniferous-Permian Ice Age, but the cold caused the decline, as the oceans could hold more gas.
Land plants without today’s fungi to help their decay did contribute to the formation of coal deposits, however. Marine transgressions however also helped build up the coal swamp deposits, delaying decay.

Willy Pete
Reply to  Willy Pete
October 9, 2017 5:00 pm

We also have the Carboniferous to thank for the evolution of amniotes, ie reptiles (including birds) and mammals.

Ron Long
Reply to  Willy Pete
October 9, 2017 5:20 pm

Is Willy Pete code for White Phosphorous? Like marker rockets in VietNam? Snowball Earth on one side and Dangerous Global Warming on the other side. What is a person to do? Wait a minute…”computer simulations”? Never mind.

Willy Pete
Reply to  Willy Pete
October 9, 2017 5:30 pm

Yup.
Better living through chemistry. Or killing, as the case may be.

sophocles
Reply to  Willy Pete
October 10, 2017 3:29 pm

and for many of the (large) limestone deposits.
Limestone = naturally ‘sequestered’ carbon. … (1)
Creation of limestone = oceanic method of pH (alkalinity) maintenance. (2).
All nature does is repeat eqns (1) and (2), which happens in far greater
quantities than mankind will ever be able to replicate.

Samuel C Cogar
Reply to  Willy Pete
October 10, 2017 6:35 am

Me thinks the majority of all coal deposits were formed as the result of the dead biomass being deposited in the shallow waters of swamps, lakes, tidal zones, inland seas, etc. ….. wherein the oxygen (O2) content of the water was extremely low or totally absent.
Without O2, microbial decomposition of dead biomass is greatly hampered.

Roger Graves
Reply to  Samuel C Cogar
October 10, 2017 10:28 am

An alternative reason for the formation of coal would be that, at the start of the carboniferous era, plants evolved lignin, which is the substance that gives stiffness to plant material – in effect, lignin makes wood woody, and hence trees can evolve. However, neither fungus nor bacteria had evolved the capability to digest lignin at that time, so dead trees simply accumulated in vast layers. A 100-metre wood deposit would later be compressed into a 10-metre coal seam, or thereabouts. The sequestration of carbon by this means would presumably have reduced the atmospheric CO2 content to something like the levels discussed here.
After a considerable time, fungi and bacteria presumably evolved a capability to digest lignin, thereby ending the carboniferous era. The CO2 content of the atmosphere would then have a chance to be restored. The question is, where did the additional CO2 come from, since dinosaurs were not known for coal mining?

lower case fred
Reply to  Samuel C Cogar
October 10, 2017 12:34 pm

Further evidence to the process of coalification being more rapid (i.e. not a really slow process after deep burial) is found in beds that were reworked with sandstone (and or shaley) casts of calamites and lepidodendron within the coal seam and seams cut by cross beds without distortion of the cross beds that would have occurred if there were a 10:1 reduction in thickness after burial.
Evidence that some sort of “swampy” process possibly involving oxygen is that underclays can be very thickly mixed with lepidodendron casts, and rapidly buried casts of upright calamites are found over seams, that were not changed to coal (both of which can have coal “skins’).
Bottom line: we really don’t know how coal was formed, but it looks a whole lot like what was growing and where had a lot to do with the kind of coal that formed.

Samuel C Cogar
Reply to  Samuel C Cogar
October 11, 2017 4:09 am

@ Roger Graves – October 10, 2017 at 10:28 am
Now I can agree with you that “lignin makes wood woody”, …….. but I cannot agree with you that it was the “woody wood” portion of dead trees accumulating in vast layers that resulted in the formation of coal.
Trees live for years n’ years, ……. but it was primarily the accumulation of the yearly “die-off” of all types of fast growing non-woody plant material that resulted in the formation of coal.
My neighbor worked as a bulldozer operator on “strip (coal) mining” jobs and he showed me a piece of petrified “tree trunk”, approx. 12” in diameter and 14” in length, that he retrieved from its vertical position in a seam of coal that he was ripping out to be loaded and hauled away. Thus the obvious explanation is, …… that seam of coal formed around the trunk of a “woody wood” tree.
So saidith Roger G:

However, neither fungus nor bacteria had evolved the capability to digest lignin at that time, so dead trees simply accumulated in vast layers.

UH, the above appears to be “old science”, …… to wit:

Fungi – Eukaryotes that grow as single cells or as large, branching networks of multicellular filaments. Mushrooms, molds, mildews, athlete’s foot, yeasts for baking/brewing. Along with land plants/animals, they are one of three major lineages of large, multicell euks that occupy terrestrial environments.
Fungi absorb their nutrition from other organisms – dead or alive.
Fungi that absorb nutrients from dead organisms are the world’s most important decomposers. A few types of organisms can digest the cellulose in plant cell walls, but fungi and only a handful of bacterial species are the ONLY organisms capable of completely digesting both the lignin and cellulose that make up wood.

https://www.flashcardmachine.com/biological-science94chapter31.html

The researchers found that land plants had evolved on Earth by about 700 million years ago and land fungi by about 1,300 million years ago — much earlier than previous estimates of around 480 million years ago, which were based on the earliest fossils of those organisms.

TA
October 9, 2017 4:55 pm

“While burning coal today causes Earth to overheat,”
Starting out with a false assumption is never a good thing. There’s no evidence burning coal causes the Earth to heat or overheat.

Bob boder
Reply to  TA
October 10, 2017 5:52 am

Well burning coal does heat the earth, well at least my living room but it’s still part of the earth

Tom Halla
October 9, 2017 4:59 pm

it does look like PIK is trying to justify models on the effects of CO2. Could be, though, as if CO2 did drop to 40ppm, that level is down on the curve where increases had a larger effect.

Sara
October 9, 2017 5:00 pm

Oh, okay, was this after Pangaea or after Gondwanaland? Or before either of them? Or both? I thought Snowball Earth was 600 million years ago. Was somebody using a time machine or something to get the exact dates?
See, I can’t keep things straight any more in these arguments about ‘XXXX cause this’ and ‘TTTT cause that’. I really can’t tell if they’re fielding a request for more money or telling us to continue using carbon-based fuels to cook, heat the house, and heat water.
So are we supposed to start doing whatever we can to start continental drift again?
I’m just trying to understand here, although I would love to ask the people who do this if they’re serious, because I can keep a straight face for a considerable length of time, but at some point, the lips start twitching, the giggles rise, and — well, I just roll of the chair on to the floor.
And anyway, as Bill Illis points out above, there has to be a sufficient land mass to help Snowball Earth proceed. So…. what was their point in publishing this?????

Jim Masterson
Reply to  Sara
October 10, 2017 11:48 am

>>
When trees in vast forests died during a time called the Carboniferous and the Permian, the carbon dioxide (CO2) they took up from the atmosphere while growing got buried; . . . .
<<
The upper Carboniferous (or late Carboniferous) was about 323.2 million years ago to 298.9 million years ago. It’s interesting that dragonflies date to about 325 Mya and had wingspans of about 30 inches. That’s a big bug! My guess is that there was enough CO2 in the dense atmosphere to support these large insects. How come the planet didn’t burn up back then?
Jim

October 9, 2017 5:01 pm

The amount of CO2 stored in Earth’s coal reserves was once big enough to push our climate out of balance.

Inevitably the story is 1. “Something” 2. CO2 levels change. 3. climate changes.
Why do these people never seem to have any concept of cause and effect? How is it they can gloss over the “Something”. Every. Single. Time.

The Reverend Badger
Reply to  TimTheToolMan
October 10, 2017 12:07 am

They do it because of $ and everyone else gets away with it. I doubt very much 100% actually believe what they are saying as many are educated intelligent people. They will jump to the other side of the ship as soon as the money moves.

October 9, 2017 5:06 pm

Models can create any kind of fantasy The programmer requires.

David Walker
October 9, 2017 5:07 pm

“using a large ensemble of computer simulations.”
Ah, more Xbox science.
Jolly good, carry on.

Patrick MJD
Reply to  David Walker
October 9, 2017 9:03 pm

“David Walker October 9, 2017 at 5:07 pm
Ah, more Xbox science.”
I don’t think it is as advanced as that. Maybe a Casio handheld game console like one of these…
https://au.pinterest.com/pin/568720259166381017/

David Walker
Reply to  Patrick MJD
October 10, 2017 4:25 pm
Bryan A
Reply to  Patrick MJD
October 10, 2017 7:38 pm

If they had used the Climate Super Computors, then it would have hit…Those things are always great for producing Doomsday scenarios

chrisB
Reply to  David Walker
October 9, 2017 10:31 pm

I am disappointed with the weak findings. They should have used an extremely vast ensemble of computer simulations. More grants please

Bryan A
Reply to  chrisB
October 10, 2017 7:40 pm

If they had used those Climate Science Super Computers, then that coming asteroid would have hit the earth in 97% of them. They are always good for predicting Doomsday Scenarios 97% of the time

Adam
October 9, 2017 5:17 pm

“Estimates based on ancient soils and fossil leaves show that they fluctuated widely and at some point sank to about 100 parts CO2 per million parts of all gases in the atmosphere, and possibly even lower.”
At what point can plant life not survive? My (non scientist) understanding was that 100 ppm was kind of pushing it for a flora apocalypse already

Willy Pete
Reply to  Adam
October 9, 2017 5:28 pm

That would indeed be starvation level for C3 plants, which is all there was in the Carboniferous. The usual estimate for CO2 during the Karoo Ice Age is around 300 ppm, but it might at times have gotten down to the level of Pleistocene glacial intervals, ie 180 ppm.

Paul of Alexandria
Reply to  Adam
October 10, 2017 10:13 am

That would actually be my question: would the (supposed) cooling be due to the lack of CO2? Or perhaps instead due to the death of much of the globe’s plant life and the loss of it’s aspirated water vapor? Previous articles here at WUWT have pointed out how much water vapor plants pump into the atmosphere, effecting local atmospheric conditions.

donb
October 9, 2017 5:30 pm

Snowball Earth occurred a few times long prior to 300 Myr ago. Reasons for chilling and then warming Earth during these have not been decided.
A lot of coal formed during the late Carboniferous and early Permian. Atmospheric CO2 went low then, and temperature also decreased. One popular idea as to why this occurred is that woody plants arose for the first time in Earth history and now produced lignin and cellulose, large organic structures, which bacteria and fungi at that time could not break down. So woody plant tissue accumulated in coal deposits, with the result CO2 was not produced from their decay, and atmospheric CO2 greatly decreased. When some tens of million years later, life developed the ability to break down these organic structures, organic decay renewed, and atmospheric CO2 rose.
This explanation implies that plant life continued through this period and possibly thrived to produce the abundant coal deposits.

Willy Pete
Reply to  donb
October 9, 2017 5:33 pm

Ice ages have less CO2 in the air than warm intervals because cold water holds more gas. Today we have abundant wood-eating bacteria and fungi, yet CO2 is low because it’s so cold. Not as cold as during glacial advances, but still cold relative to most of the Phanerozoic Eon.

Reply to  Willy Pete
October 9, 2017 9:07 pm

The higher fungi evolved at the end of the Ediacaran, which fauna is so wierd that some have speculated that it was, in fact, fungi. Fungal spores are extremely abundant in Permian extinction residues…

Crispin in Waterloo but really in Beijing
Reply to  donb
October 9, 2017 11:52 pm

Donb
There is a kind of hole in that theory which is that if the drawdown made it cold, why would it warm again if the carbon was still sequestered as coal? To ‘get it warm’ it would need a new source of carbon. What was that? The oceans suddenly? Hydrocarbon oil from deep in the earth?weathering rock?
One possibility is volcanoes.

Zurab Abayev
October 9, 2017 5:41 pm

How much coal did Ordovician form?
Sorry, nonsense article

Willy Pete
Reply to  Zurab Abayev
October 9, 2017 5:43 pm

There were very few land plants in the Ordovician, and no trees at all.
By the Carboniferous, however, lycopods grew up to 100 feet tall.

RAH
Reply to  Willy Pete
October 9, 2017 8:52 pm

Ok.
Something that I have had a question about for some time. During the Carboniferous both O2 and CO2 were at much higher concentrations in the atmosphere compared to today. Why?
And with those two gases being in such a high proportion then I would assume then Nitrogen concentration in the atmosphere decreased?

Willy Pete
Reply to  Willy Pete
October 9, 2017 9:07 pm

RAH,
During the Carboniferous ice age, CO2 was about the same as today. During most of the period, O2 was famously higher.
So either the atmosphere was denser or N2 proportion was lower. Probably the former, ie about the same amount of nitrogen, but more oxygen.

RAH
Reply to  Willy Pete
October 9, 2017 9:36 pm

From what I’ve read CO2 is believed to have ranged up to 800 ppm for the period. Would it not have had to have been high for such prodigious growth of vegetation? It was pretty darn hot, up to 14c more than today for much of the period as I understand it. Not saying Co2 caused that but saying that the ability of the oceans to hold CO2 would be reduced when the waters are warmer. And would not a denser atmosphere result in higher pressures and that would show up in the fossil record in adaptive traits in flora and fauna to better sustain the pressure?
Not arguing. Just questioning to try and get a handle on what were really the conditions during most of the period. Kind of difficult to find the answers to these questions all in one place or reference. Just questions that have been bouncing around in my skull for some time. So much knowledge here so I’m trying to take advantage of it.

Willy Pete
Reply to  Willy Pete
October 9, 2017 9:52 pm

RAH,
The Carboniferous in North America is divided into two periods, the Mississippian and Pennsylvanian. This reflects two quite different climates.
There was probably already some glaciation at the end of the Devonian Period, but the great ice age didn’t hit until the Pennsylvanian, with perhaps the last age (Serpukhovian) of the Mississippian. And it persisted well into the Permian.
An average of 800 ppm for the whole period to me seems high, since during the Pennsylvanian it was often as low or lower than today.

Zurab Abayev
Reply to  Willy Pete
October 10, 2017 5:40 am

my point exactly. Ordovician is well known for it’s true “snowball earth” period – and no plants to form a coal; ergo, planetary mechanisms are primary, and everything else is secondary

RAH
Reply to  Zurab Abayev
October 9, 2017 10:03 pm

Thanks for your responses Willy Pete.
BTW WP is a nasty weapon but one that has saved a heck of a lot of US troops lives. During WW II the Germans and the Japanese hated to be shelled with WP rounds. Neither could ever produce anything like the quantity the US did. They allowed the VT fuse (proximity fuze) to be used by Army artillery just in time for it to be deployed during the Battle of the Bulge. Fusing a WP round with the VT was just devastating. Even Patton was impressed by how deadly it was.

Willy Pete
Reply to  RAH
October 9, 2017 10:21 pm

Patton also admitted that we had a lot to learn about using proximity fuzes. In the woods, old fuzes were better, since the foliage caused detonations above the trees with VT fuzes, whereas in the trees caused more death, destruction and damage.
I witnessed the effects of M34 Willie Pete smoke grenades in the first Gulf War, although they’re most associated with Vietnam. We also used them in the late unpleasantnesses in Iraq and Afghanistan. Very useful munitions.

reallyskeptical
October 9, 2017 5:41 pm

thinking we should keep the C in the ground until we need it some day…

Willy Pete
Reply to  reallyskeptical
October 9, 2017 5:45 pm

We need a lot more of it in the air right now. Triple present concentration would be ideal.
Trillions of plants can’t be wrong.

Reply to  Willy Pete
October 12, 2017 8:33 am

funnily that would alter local climate 😀 The extra plants, not the CO2 #landchange

MarkW
Reply to  reallyskeptical
October 10, 2017 6:37 am

We need it now.
We have no idea what the needs of the future are going to be.

October 9, 2017 5:50 pm

So, why didn’t the vast coal deposits formed during the steamy Cretaceous Period cool the earth?

Willy Pete
Reply to  wryheat2
October 9, 2017 6:02 pm

The authors would say because Carboniferous plants didn’t decay, releasing CO2, due to lack of bacteria and fungi adapted to breaking down lignin. But these wood-eaters had long been around by the Cretaceous.

Bob Burban
October 9, 2017 5:50 pm

The biggest carbon repository on Earth by a very long chalk is not coal but calcium and calcium-magnesium carbonate …. limestones and dolomites, deposited in water either as chemical sediments or as shells. That alone makes this pap what it is: genuine, 24 carat unmitigated pap.

Reply to  Bob Burban
October 9, 2017 6:10 pm

Excellent, Bob!

Ron Long
Reply to  Bob Burban
October 10, 2017 2:52 am

Right on Bob! I commonly tell friends that so many reefs die that they have a special name for them: limestone. Of course most limestone is debris from living reefs, but sometimes a reef dies and is preserved insitu, then it’s called a bioherm.

ACK
Reply to  Bob Burban
October 10, 2017 3:12 am

You would think that if the Earth only just escaped becoming a snowball then it would show signs of severe cooling. Yet look at the Permian. Away from the southern continents, marked by glacial deposits and temperate coals, the Permian is represented by reefs (SW USA, Arctic Canada, Norway and Russia) or by desert deposits containing the world’s largest assemblage of evaporites. Some of the Permian potash evaporites imply high temperatures during their formation.
I would back the evidence from the rocks formed at the time over model fantasies very time.
With respect to the Cretaceous, more important than its coals are the abundant and widespread oil and gas source rocks that probably removed a similar amount of carbon as all the Carboniferous and Permian coals put together. Cretaceous cooling? No evidence for.

commieBob
October 9, 2017 5:51 pm

I’ll tell you why this paper was published.
A paper won’t be published unless it provides interesting results. It doesn’t matter if the results are wrong because there’s no punishment for being wrong. If it’s interesting and doesn’t contradict the prevailing bias, the paper stands a reasonable chance of being published.
You won’t make tenure track unless you publish. What do you think is almost guaranteed to happen? link

Ellen
October 9, 2017 6:00 pm

You have to throw solar evolution into the mix. As our sun burns through its supply of hydrogen, it gets hotter by about 10 percent every 1.1 billion years. The Carboniferous era was something like 300-360 million years ago, so the sun would have been perhaps 3 percent cooler. That has to have had some effect.

Willy Pete
Reply to  Ellen
October 9, 2017 6:06 pm

It does, but we’re in an ice age now, and earth was probably at its hottest of the Phanerozoic Eon during the Cretaceous Period of the Mesozoic Era and first two epochs of the Paleogene Period of our current Cenozoic Era. The sun was about one percent weaker than now during the middle of the Cretaceous, ie 110 Ma.

Bob boder
Reply to  Ellen
October 10, 2017 6:02 am

The earth cools as it gets older, should have an effect as well.

October 9, 2017 6:08 pm

Confirmation bias in action!
There are other more common carbonaceous rocks, e.g. limestone, marble, carbonates, shales, metasomatites, etc.; basically all sediment layers where dead wildlife accumulate.
Large portions of the World’s crust is now composed of carbonaceous rock, far outweighing coal and oil deposits.
All of Earth’s oceans, lakes and tidal waters are major producers of carbonaceous material.
All these alleged researchers, aka yahoos, had to do was conduct research and consult some geologists.
Instead, these alleged researchers fabricate specious claims and write bogus announcements while ignoring carbon’s total role in Earth’s geology

Clyde Spencer
Reply to  ATheoK
October 9, 2017 8:19 pm

And the Paleozoic carbonates also typically have abundant hydrocarbons. Even the Paleozoic black shales are rich in organic material. That is, carbon was being sequestered continuously throughout the Paleozoic, not just episodically during the carboniferous.

Brian Pratt
October 9, 2017 6:15 pm

First, the press release goofed and it is Proceedings of the National Academy of Sciences. It is peer-reviewed, not to say that is necessarily rigorous. My issue with all these suppositions about Carboniferous paleoclimate and atmosphere is that nobody as far as I can tell has calculated how much coal was deposited in the Pennsylvanian (given also the need to estimate also what might have since been eroded and recycled). This is necessary to gauge the change in pCO2 due to geological sequestration. The author pays no heed to younger times of widespread coal deposition. Nor does he mention the now pretty well established glaciation in the Appalachian Mountains during the latest Devonian (Famennian).

Willy Pete
Reply to  Brian Pratt
October 9, 2017 6:21 pm

Maybe Feulner gets more precise in the body of his article, but in the abstract he says only “the bulk of Earth’s coal deposits”.
The bulk of Earth’s coal deposits used as fossil fuel today was formed from plant debris during the late Carboniferous and early Permian periods. The high burial rate of organic carbon correlates with a significant drawdown of atmospheric carbon dioxide (CO2) at that time. A recent analysis of a high-resolution record reveals large orbitally driven variations in atmospheric CO2 concentration between ∼∼150 and 700 ppm for the latest Carboniferous and very low values of 100 ±± 80 ppm for the earliest Permian. Here, I explore the sensitivity of the climate around the Carboniferous/Permian boundary to changes in Earth’s orbital parameters and in atmospheric CO2 using a coupled climate model. The coldest orbital configurations are characterized by large axial tilt and small eccentricities of Earth’s elliptical orbit, whereas the warmest configuration occurs at minimum tilt, maximum eccentricity, and a perihelion passage during Northern hemisphere spring. Global glaciation occurs at CO2 concentrations <40 ppm, suggesting a rather narrow escape from a fully glaciated Snowball Earth state given the low levels and large fluctuations of atmospheric CO2. These findings highlight the importance of orbital cycles for the climate and carbon cycle during the late Paleozoic ice age and the climatic significance of the fossil carbon stored in Earth’s coal deposits.

donb
Reply to  Willy Pete
October 9, 2017 6:27 pm

You realize that gravitational interactions among planets decrease the accuracy of estimates of Earth’s orbital parameters as one progresses back in time. Making calculations back 1 Myr may be O.K., but back 300 Myr is highly uncertain.

MarkW
Reply to  Willy Pete
October 10, 2017 6:41 am

Interesting, but not relevant.
All years are based on the current length of the year only.

Andrew
October 9, 2017 6:21 pm

We need to keep CO2 below 7500ppm, te highest concentration tested historically and found to be safe.

Willy Pete
Reply to  Andrew
October 9, 2017 6:32 pm

As long as oxygen isn’t correspondingly low. During the Cambrian, when CO2 was around 7000 ppm, there wasn’t enough O2 in the air to meet human requirements. It might have been only 10% rather than today’s 21%. At most, perhaps 12.5%.

Reply to  Willy Pete
October 9, 2017 8:15 pm

Isn’t there a 1-1 tradeoff between O2 & CO2? (C + O2 => CO2)
If I burn coal and raise the CO2 by 1000 PPM, doesn’t that decease the O2 by 1000 PPM (0.1%)?
If so, raising the CO2 to 7500 PPM would reduce the O2 from 21% to 20.3%

Willy Pete
Reply to  Willy Pete
October 9, 2017 8:47 pm

Mike,
CO2 displaces N2 and Ar as well as O2, so just increasing CO2 doesn’t have much effect directly on O2. The underlying conditions dictating the chemistry of the atmosphere however make the relative concentrations of CO2 and O2 more dramatic. Biology has a lot to do with it.

MarkW
Reply to  Willy Pete
October 10, 2017 6:42 am

More CO2 means more plants.
More plants means more O2.

Patrick MJD
Reply to  Andrew
October 9, 2017 7:18 pm

Submarines operate at up to ~11000ppm.

The Reverend Badger
Reply to  Patrick MJD
October 10, 2017 12:15 am

Submariners operate at up to 11,000 ppm, submarines can go a lot higher without those pesky carbon based lifeforms.

Richard
October 9, 2017 7:13 pm

Science:
Forming and testing a hypothesis based on empirical observations.
Climate science:
Finding or creating observations and computer model output that suppoet your theory.

Patrick MJD
Reply to  Richard
October 9, 2017 7:50 pm

Ah come on now, are you saying they have made it all up? Oh wait…

The Reverend Badger
Reply to  Richard
October 10, 2017 12:16 am

…support your theory and grant income.
FTFY

October 9, 2017 7:29 pm

“The study examines the sensitivity of the climate in a specific period of Earth’s deep past by using a large ensemble of computer simulations.”
Dowsing rods would have a better chance of producing meaningful results

JBom
October 9, 2017 8:06 pm

I would posit that the movie ‘Iron Sky’ (2012) is actually about the Potsdam Institute!
Sieg Heil. Ha ha.

William
Reply to  JBom
October 9, 2017 8:52 pm

Based on the trailer, this looks like a pretty cool movie.
It has all the classic elements: good guys, bad guys, disasters, and everybody dies in the end.
What could go wrong?
Is it on Netflix? Gotta check it out. Load up with popcorn first…………..

Paul Linsay
Reply to  William
October 10, 2017 7:09 am

Amazon prime. Try “Europa Report” on Netflix, it’s much better, and about a very cold planet, appropriate for the blog post.

willhaas
October 9, 2017 8:16 pm

A major problem with this is that there is no real evidence that CO2 has any effect on climate. There is no such evidence in the paleoclimate record. There is evidence that warmer temperatures caused more CO2 to enter the atmosphere but there is no real evidenct that the additional CO2 added to warming. There is plenty of sceintific rational to support the idea that the climste sensivity of CO2 is really zero. If CO2 really affected climate then one would expect that the increase in CO2 over the past 30 years would have caused at least a measureable increase in the dry lapse rate in the troposphere but such has not happened. The AGW conjecture is based upon only partial science and is full of flaws. The AGW conjecture depends upon the existance of a radiant greenhouse effect caused by trace gases with LWIR absorption bands but no such radiant greenhouse effect has been observed anywhere in the solar system including the Earth. It is a convective greenhouse effect, as derived from first principals, that keeps the Earth’s surface 33 degrees C warmer than it might otherwise be. 33 degrees C is the derived amount and 33 degrees C is what has been observed. Additional warming caused by a radiant greenhouse effect has not been observed. The radaint greenhouse effect is sceince fiction which renders the AGW conjecture as science fiction as well. The article seems to ignore the effect of carbonate rock formation on the CO2 level in the Earth’s atmosphere.

The Reverend Badger
Reply to  willhaas
October 10, 2017 12:22 am

I think you are at least half right. I doubt the 33 degrees. Comparison with the Moon would seem to suggest rather more for the ATE if you do the math.(see that infamous paper by Nikolov & Zeller). I am not sure they are right either but 33 degrees does look too low by my reckoning. More work could be done in this area. We need several people working on it with different views to thrash out the mathematics and ideas in more detail. Getting the ATE figure right is pretty fundamental to all this stuff.

Reply to  willhaas
October 10, 2017 7:20 am

. It is a convective greenhouse effect, as derived from first principals, that keeps the Earth’s surface 33 degrees C warmer than it might otherwise be. 33 degrees C is the derived amount and 33 degrees C is what has been observed. Additional warming caused by a radiant greenhouse effect has not been observed. The radaint greenhouse effect is sceince fiction which renders the AGW conjecture as science fiction as well.

It’s at least half from water vapor, but because it’s condensing at this temp/pressure it’s a regulating mechanism.
https://micro6500blog.wordpress.com/2016/12/01/observational-evidence-for-a-nonlinear-night-time-cooling-mechanism/
But you are right about Co2, it’s effect is near zero.

October 9, 2017 9:31 pm

Well at least the Potsdam Institute is consistent with their low and high CO2 predicted effects on global temperature. But maybe they should have a more in depth look at the negative feedbacks, since their results seem to be “accentuating the positive” when it comes to feedbacks. A hint here Potsdamers, a degree increase at sea level wants to put 7% more water vapour into the air above the water. The 7% more water vapour wants to make up to 7% more clouds somewhere a couple of days later a few hundred miles away…but before the 7% more cloud can reflect a hundred watts per square metre of sunlight back into outer space, a lot of the water rains down from the sky and the clouds dissipate….net result, doubling of CO2 doesn’t increase ground level temperature very much, about a degree C.

Don Easterbrook
October 9, 2017 9:56 pm

The folks in Potsdam need to look at the Pleistocene glacial record–CO2 ALWAYS lags climate change. The reason for low CO2 was cooling of the oceans which allowed the oceans to take in more CO2, not the other way around. The other problem with this study is that no one has yet proven that CO2 has any significant effect on climate.

Reply to  Don Easterbrook
October 12, 2017 8:37 am

The latter is a biggy that today, still, no one has yet to even provide ANY evidence. An unobserved mechanism is not evidence, and that to date is all they have.
Also this study stinks of brainstorming for ideas for a study, and is childlike intuitive thinking.
There is no promotion of real science here, so the results are going to be like as they are because these people have 0 self awareness, they cannot see how ludicrous this study is, it’s not even a study.
They no doubt had an idea of the conclusion, and merely modeled to support that.

Warren in New Zealand
October 9, 2017 10:25 pm

“The study examines the sensitivity of the climate in a specific period of Earth’s deep past by using a large ensemble of computer simulations.”
There you go, PlayStation again.
I’m almost ready to go Las Vegas on the next bloody so called peer reviewed and “as reported in the MSM” person/people/institute that play computer games and think they are actual Earth Scientists
I really doubt that any of them even have any Horticultural Qualifications, just Hort 101 would remove the CO2 =EVIL mindset.

October 9, 2017 10:42 pm

We should definitely keep CO2 levels in the atmosphere below 450 parts per million to keep our climate stable, and ideally much lower than that.

Feulner in PIK seems to believe mankind has the power to adjust average global outside air composition and “stabilise climate”? Funny. What’s next?

Crispin in Waterloo but really in Beijing
October 9, 2017 11:25 pm

This sentence is nothing less than bizarre:
“The amount of CO2 stored in Earth’s coal reserves was once big enough to push our climate out of balance. When released by burning the coal, the CO2 is again destabilizing the Earth system.”
Destabilizing what exactly? What a crock! And waht was the CO2 concentration when this period of vast global growth took place?
2000 ppm? Is that correct?
And now 450 ppm is going to kills us all?
What they really found is that there is no threat whatsoever from 2000 ppm and they are trying to bury the good news under a cloud of pretended danger, saying that being close to a frozen snowball under a mile of ice is preferable to living on a rich, green and productive planet.

Latitude
Reply to  Crispin in Waterloo but really in Beijing
October 10, 2017 4:49 am

What they really found is….CO2 is sequestered and unless it’s replaced..it becomes so limiting we all die

jolan
October 10, 2017 12:36 am

“Earth’s past teaches us that periods of rapid warming were often associated with mass extinction events” When did this happen?

Editor
October 10, 2017 12:40 am

The “low” CO2 levels, which they claim had Earth teetering on the verge of snowball-ville were about 400-450 ppm.comment image
Note the CO2 minimum of the Mississippian (Lower Carboniferous), all of the Pennsylvanian (Upper Carboniferous) and minimum of the Permian.
These clowns are actually saying that 400-450 ppm is low enough to be on the verge of “snowball Earth;” but it’s imperative to keep CO2 below 450 ppm to avoid “overheating.”

Reply to  David Middleton
October 10, 2017 1:52 am

Earthly greenhouse ‘no return’ tipping point happened already in the Cambrian and Ordovician biodiversification periods? And now it’s come back to haunt us? Again? Ooh no, this time we’re doomed for real. /sarc

Toneb
Reply to  David Middleton
October 10, 2017 2:04 am

“These clowns are actually saying that 400-450 ppm is low enough to be on the verge of “snowball Earth;” but it’s imperative to keep CO2 below 450 ppm to avoid “overheating.””
You are not comparing apples with apples David.
300m ya the Sun was ~2% fainter..comment image
Dont you think that played a part?

Reply to  Toneb
October 10, 2017 3:06 am

You seem to be on the right track this time Toneb. The sun warms the earth – enough to resolve devastating glaciations. A far more interesting question is what causes glaciations?
Either way and based on NASA’s illustration below, the mankind influences it less than a tick hair swings an elephant’s tail:comment image

Reply to  Toneb
October 10, 2017 3:57 am

Not at all.comment image

Figure 2.
Open in figure viewer
Estimated deviations in equatorial sea-surface temperatures, from the modern mean value, after removing the warming influence of solar evolution. The upper curve assumes the maximum SST, maximum climate sensitivity and minimum polar amplification. The lower curve assumes the smallest SST, smallest climate sensitivity and largest polar amplification.

http://onlinelibrary.wiley.com/doi/10.1111/ter.12097/full
“After removing the warming influence of solar evolution,” the Pennsylvanian with its 450 ppm CO2 was at least as warm as present day Earth.

tty
October 10, 2017 1:08 am

“Earth’s past teaches us that periods of rapid warming were often associated with mass extinction events”
Very doubtful. The reason for most mass extinctions is quite uncertain, except for the K/Pg one which was due to an asteroid impact.
And the only case of ancient “rapid warming” that is well documented, the PETM, was not associated with a mass extinction, quite the opposite (rapid diversification) as a matter of fact.
And during the present glacial age with very frequent extreme climate shifts extinctions almost always occur during cooling intervals, not warming.

tty
October 10, 2017 1:48 am

Actually the pCO2 during the Permo-Carboniferous glaciations is quite uncertain. It is known to have been rather low (meaning <1000 ppm) , at least during some intervals, but the best pCO2 proxy for such old deposits (pedogenic carbonates) is known to be very insensitive for low pCO2 levels, and for example can’t really distinguish 0 from 500 ppm, while plant-based proxies are very uncertain that far back since the plants were very different from even the most conservative living forms (with known reactions to pCO2).
http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1103&context=geosciencefacpub
It is however worth noting that C4 photosynthesis, which has evolved independently about 60 times in different plant groups as an adaptation to low CO2 levels during the present glacial epoch never evolved during the Permo-Carboniferous, though in this case too, the archaic plants living then may not have had the ability to evolve it.

Ed Zuiderwijk
October 10, 2017 2:06 am

All this is based on the idee that CO2 drives the climate. It doesn’t, not at at levels higher than 150 ppm. CO2 depletion will therefore not have caused snowball Earth, just as current increases will not lead to hothouse Earth.

Moderately Cross of East Anglia
October 10, 2017 2:10 am

Just a short point to add to the many excellent criticisms of this uninformative Potsdam porridge of speculative dementia. Notice their use of climate perjorative terminology about the Carboniferous accumulation of coal pushing the Earth’s climate “out of balance ” in particular. Last time I looked the Carboniferous period lasted about 50 million years, so while climate varied through its various epochs and stages there wasn’t exactly a sudden crisis. Not that that stops them then racing to claim that the last 50 years is suddenly putting the Earth’s climate out of balance again – on the basis of nothing that can be described as convincing evidence. And of course ignoring all the other climate changes between the Carboniferous and today like they didn’t happen, some of which really were sudden by cmparison.
These people need to be made to listen to a lesson on Earth history by someone who knows what they are talking about – where are you David Middleton?
Letting down the reputation of German science at Potsdam seems to be their aim, surely they cannot be serious.

Robert of Ottawa
October 10, 2017 3:06 am

While some of the changes in temperature at that time can clearly be attributed to how our planet’s axis was tilted
SOME?

Sandy In Limousin
October 10, 2017 4:10 am

What about all the Carbon stored in CaCO3? Most if not all the C must have come from the atmosphere either directly or indirectly. About 1% of the crust in total?
Present-day production of CaCO3 in tne world ocean is calculated to be about 5 billion tons

marque2
October 10, 2017 4:34 am

So all the coal dropped temps by a degree and when we put it back the temps will go up much more? Seems dubious to me.

October 10, 2017 5:04 am

The author asserts CO2 should be kept below 450 ppm. What is this conclusion based on, this article and his research? Seems like a very narrow focus without much consideration for other variables that affect overall climate on earth. In fact that is what has been missing in all these articles is a complete look at how all this systems work together to affect global climate. IMHO, the sun is the biggest driver. Already the sun is entering a period of low sun spot activity. I suspect things will be cooler and perhaps colder as we approach 2025-2030. If we are at 400 ppm already, it won’t be long before we hit 450 ppm. Get ready for an “unstable planet earth?” I won’t be surprised if we are cooler.

Bill Illis
October 10, 2017 5:06 am

This is why there was an on-and-off ice age 300 million years ago. Gondwana drifted across the South Pole. This wasn’t a continuous ice age since the landmasses was pushed below sea level by the glacial load at various times and the glaciers melted back.
http://www.pik-potsdam.de/~stock/lectures/earths_climate_ruddiman/ch05-plate%20tectonics%20and%20climate/figure%2005-10.jpg
This is what it looked like at 300 million years ago (poor Antarctica, it always seems to get stuck at the south pole and glaciated, 4 different epochs now).comment image
In fact, this continental drift of Gondwana was also responsible for the Ordovician ice age as well starting at 456 million years ago and culminating in the Ordovician extinction 443 million years ago. The actual Snowball Earth episodes are shown here as well.comment image
This is a close-up of the Carboniferous ice age. It wasn’t continuously cold. There are even warm periods. The coal was formed in North America and Europe and Asia which were more-or-less at the equator at the time. Large forests grew, the high Oxygen content of the atmosphere repeatedly burned them to the ground. Forest fires could burn right across a continent at the time. Sea level rose and fell as the glaciers came and went on Gondwana, occasionally burying the burnt remnants of the forests under ocean sediment. Over millions of years, nice coal in North America and Europe and Asia. NONE in Gondwana.comment image

tty
Reply to  Bill Illis
October 10, 2017 6:33 am

While there is only a little Carboniferous coal in Australia it has huge early Permian coal deposits. Those came from cold-temperate swamp forests, an analogue to todays extensive bogs in the boreal taiga zone.

Alex
Reply to  Bill Illis
October 10, 2017 6:37 am

Bill – re four glaciations in Gondwana. Are you sure you want to go ahead and invest in housing real estate in Antarctica?

sunsettommy
Reply to  Bill Illis
October 10, 2017 7:55 am

Interesting Bill, can you provide a source for the research?

WB Wilson
Reply to  Bill Illis
October 10, 2017 10:54 am

Bill, thanks for the clear and concise presentation of the geologic data and interpretations.
As a creature of the IPCC, Potsdam Institute’s bias and agenda are revealed.

Coach Springer
October 10, 2017 5:36 am

Overheat? Dangerous? We aren’t even globally comfortable yet.

Keith J
October 10, 2017 5:42 am

No. Far more carbon is sunk in methane clathrate than coal and petroleum combined. Methane Clathrate is more stable in a snowball world hypothesis so that guess is wrong. ..as is the claim carbon dioxide regulates climate.
This isn’t a Goldilocks situation, it is a system of negative Feedbacks.

jclarke341
October 10, 2017 6:10 am

“The amount of CO2 stored in Earth’s coal reserves was once big enough to push our climate out of balance.”
The whole notion of ‘balance’ is environmental wacko nonsense. What does that even mean? Scientifically, it means nothing. In this context, it is a propaganda word. It implies that there is a ‘proper’ way for the atmosphere to be; a right way and a wrong way. The article may sound scientific to the layman, put it is clearly a propaganda piece, with no scientific value. It is based on the false premise that the atmosphere should be a certain way. If we accept this subtle assumption, and begin arguing the individual points in the article, we are already caught in their deceptive web and pacifly accepting that maybe we should do something to ‘fix’ our climate.
If I may paraphrase Gandalf: The climate is not and has never been ‘out of balance’. It is always precisely what it means to be.

MarkW
Reply to  jclarke341
October 10, 2017 6:50 am

If the CO2 stored in coal is enough to push the climate out of balance, does that mean that before the CO2 was stored in the coal, the climate was out of balance?

Reply to  MarkW
October 10, 2017 7:51 am

That kind of logic is not permitted in Potsdam

Toneb
Reply to  jclarke341
October 10, 2017 6:59 am

“The whole notion of ‘balance’ is environmental wacko nonsense. What does that even mean? Scientifically, it means nothing.”
http://www.indiana.edu/~geol105b/1425chap8.htm
“Owing to its large reservoir of reactive carbon (see table above) and the long timescale of its turnover, the ocean effectively controls atmospheric CO2 levels on the time scale of millennia. It is the DYNAMIC BALANCE between the CO2 content of the atmosphere (via dissolution into ocean waters) and the biologically driven net transport of organic (dead plant and animal matter) and inorganic carbon (calcium carbonate) to the deep ocean (biological pump) which largely determines the atmospheric CO2 levels.”
(MY CAPS)

Bruce Cobb
October 10, 2017 6:54 am

These climate geniuses seem to think that correlation = causation. Come to think of it, they do have a point, as the following graph clearly shows:
http://www.paulmacrae.com/wp-content/uploads/2008/06/co2-levels-over-time1.jpg

October 10, 2017 7:17 am

I don’t understand papers like this where the a-priori assumption is CO2 levels is the controlling thermostat of the planet. Since that’s not true, anything built on top of that non-existent foundation is false.
Water vapor in the form of clouds and sunlight reflected as ice are the main determinants of our planets temperature as those factors control how much of the sun’s radiation is available to heat the earth. Anything that shifts that water albedo set of effects will change temps.
Our geologically recent glaciations started when Antarctica drifted to the south pole dramatically changing the albedo.
I just sigh at the state of climate ‘science’ when religious like assumptions regarding CO2 are the basis of a whole flawed paper.
Sigh………

JimG1
October 10, 2017 7:34 am

Let’s see, we have continental plate migration, different flora/fauna, ocean current blocking, chg gasses changing (incuding h2o vapor), axial tilt changes, orbital changes, precession changes, tsi changes over that period of time, volcanic intrusions, and the very composition of the chemical geologic surface of the earth changing. Seems simple enough to me to figure out what happened when and why. Sorry folks, but this is a very chaotic system and most of climate science is a result of heads stuffed into various fundaments along the way.

Jaakko Kateenkorva
October 10, 2017 7:41 am

Meanwhile in the rest of the solar system, carbon is the 4th most common chemical element. Earth is presumed to have only one tenth of it.
Source: http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/elabund.html

Steve Zell
October 10, 2017 7:43 am

It’s hard to imagine that a period of low CO2 concentrations would lead to GLOBAL glaciation.
As Higley7 pointed out above, water vapor absorbs infrared radiation across a much wider range of frequencies/wavelengths than CO2, and is present in much higher concentrations in the atmosphere. About 70% of the Earth’s surface is covered by water, so that even in a low-CO2 period, there would be enough water vapor in the atmosphere over the oceans to prevent freezing of the tropical oceans. Even if there was massive glaciation of continents into temperate areas, along coastlines the large temperature difference between oceans and continents would cause storms to form, bringing rain to coastal areas and allowing them to remain ice-free, and support land-based life.

Toneb
Reply to  Steve Zell
October 10, 2017 12:22 pm

About 70% of the Earth’s surface is covered by water, so that even in a low-CO2 period, there would be enough water vapor in the atmosphere over the oceans to prevent freezing of the tropical oceans.”
Yes indeed … trouble is – water precipitates out of the atmosphere in around 10 days after evaporation.
CO2 doesn’t. With out it the earth would soon lose atmospheric WV and plunge into an iceball……comment image?w=720

Reply to  Toneb
October 10, 2017 4:54 pm

Toneb writes

Yes indeed … trouble is – water precipitates out of the atmosphere in around 10 days after evaporation.

The trouble with this line of reasoning is that evaporation is always happening to replace that precipitation and at no time is there no global atmospheric water vapor. Whether there is local water vapor following rain or not, the amount of energy deposited into the oceans from the sun is the same and so ultimately resulting evaporation will continue.
The only way the non condensing gas CO2 can control anything over water vapor is by definition brought on by belief and flawed models. Its not one of those settled scientific facts.

Toneb
Reply to  Toneb
October 11, 2017 1:27 am

“The trouble with this line of reasoning is that evaporation is always happening to replace that precipitation and at no time is there no global atmospheric water vapor.”
That is becasue a floor is set by non-condensing atmospheric GHGs.
Remove that ‘floor’ and the atmosphere would keep condensing out WV at a greater rate than evaporation. CO2 is most ‘effective’ in dry air and without it, the NH land-masses will dominate through it’s winter(s) and deposit more and more snow/ice – leading to a cooling albedo feedback, as shown by the posted graph repruducing empirical physics.

Wim Röst
Reply to  Toneb
October 11, 2017 9:32 am

Toneb October 10, 2017 at 12:22 pm, fig. 2
WR: your fig. 2 shows a model in which the noncondensing GHG’s are removed. What would be the result, when you run the same model but with only the condensing GHG’s removed? Which temperatures will result?
Water vapour is the dominating greenhouse gas (GHG).

Reply to  Toneb
October 11, 2017 3:33 pm

Toneb writes

That is becasue a floor is set by non-condensing atmospheric GHGs.
Remove that ‘floor’ and the atmosphere would keep condensing out WV at a greater rate than evaporation.

That is the prevailing belief but is not a fact in our atmosphere.

Toneb
Reply to  Toneb
October 12, 2017 8:19 am

“That is the prevailing belief but is not a fact in our atmosphere.”
Sorry Tim, just saying so doesn’t cut it.

Toneb
Reply to  Toneb
October 12, 2017 8:26 am

“What would be the result, when you run the same model but with only the condensing GHG’s removed? Which temperatures will result?”
WR: I don’t know if that has been done, but I imagine that we would cool most of the way towards the Earth’s effective temp of -18C.
But of course you would have removed all water – oceans, ice, snow, clouds – so albedo would be reduced, allowing more incoming shortwave to compensate.
The thing about non-condensing GHGs is that the cooling sets up an albedo and evaporation feedback. Greater albedo > cooling > reduced evap > cooling.

Wim Röst
Reply to  Toneb
October 12, 2017 9:49 am

Toneb October 12, 2017 at 8:26 am: “The thing about non-condensing GHGs is that the cooling sets up an albedo and evaporation feedback. Greater albedo > cooling > reduced evap > cooling.”
WR: and also:
“The thing about CONDENSING GHGs is that the cooling sets up an albedo and evaporation feedback. Greater albedo > cooling > reduced evap > cooling.”

Reply to  Toneb
October 13, 2017 8:27 pm

Toneb writes

Sorry Tim, just saying so doesn’t cut it.

Ironically…right back at ya. “Backing up” your claim with model results is not evidence.

October 10, 2017 7:50 am

the renowned Proceedings of the US Academy of Sciences

Actually, it’s called Proceedings of the National Academy of Sciences. You’d think they could get that right, at least.
I know, it’s only the news release, but still, scientists are supposed to be meticulous in their facts.
And BTW, the idea that low CO2 due to sequestration caused the Carboniferous ice age, has been around for as long as the “CO2 is the control knob” concept, I first read it back in the 1980s. It’s rather obvious when you look at the amount of Lower Carboniferous coal and Upper Carboniferous limestone.

Willy Pete
Reply to  Smart Rock
October 10, 2017 1:30 pm

But the cold preceded the drop in CO2. With more CO2 in the oceans, limestone production picked up. A positive feedback effect! But not what alarmists have in mind.

Reply to  Smart Rock
October 10, 2017 1:36 pm

They’re confusing it with the Soviet Union’s Academy of Sciences. Freudian slip.

TxVet
October 10, 2017 9:08 am

I call BS on this article.

October 10, 2017 1:28 pm

While burning coal today causes Earth to overheat,
When an article starts with a sentence like “while green men on the moon are responsible for Liverpool football club’s recent poor away form”, how is one meant to take seriously anything that follows?

October 10, 2017 8:36 pm

Since the coal stayed put, why isn’t the earth still a snowball?

October 11, 2017 3:46 pm

“Today, CO2 levels in the atmosphere have reached more than 400 parts per million. Carbon dioxide acts as a greenhouse gas: the Sun warms Earth’s surface, but most of the heat radiated by the surface escapes into space; ”
HEAT RADIATED ESCAPES INTO SPACE !
Yes. So how comes your conclusion
“CO2 and other greenhouse gases hinder part of this heat from escaping, hence warming the planet.”
Anthony Watts, my sympathy.

October 11, 2017 9:57 pm

““It is quite an irony that forming the coal that today is a major factor for dangerous global warming once almost lead to global glaciation,””
No evidence for any of this nonsense, past glaciation nor present warming.
Potscam Institute

October 11, 2017 10:03 pm

This is infant logic, “CO2 causes warming, so any process that took CO2 from the atmosphere causes cooling” “But lets forget anything else the earth might be doing and lets not admit we have 0 idea what happened 700 million years ago because there is no data for anything from then more or less”
It’s like white holes “Black holes suck in, and eventually must fill up” << Child's intuitive thinking, as is the above

Gabro
Reply to  Mark - Helsinki
October 11, 2017 10:11 pm

There is ample evidence of past Snowball Earths.

Reply to  Gabro
October 12, 2017 8:39 am

Snowball earths are not being questioned, CO2 being the cause is the question. 😛

Reply to  Gabro
October 12, 2017 8:40 am

The fact they used models proves the point. Output, pfft, No data here, nothing to see folks, move along

October 12, 2017 8:44 am

Theoretical sciences are so full of bunk these days, not just climate science.
Mathematicians have created a kind of thing now where they create something with mathematics and then apply real physical properties to the output.
UGH Mathematics are only useful when we can validate the results. Otherwise you end up with Dark Matter (Cern admitted 0 trace of this magical stuff FYI and it’s going to be bunk by 2020 and dropped going by the research coming in in 2017)
Schmidt is creating “real world warming” with his average maths and poor statistical skills. The IPCC models
These are the same thing, mathematics turned into real things, real threats.
This scientism via mathematics has to be stopped.