Carbon release and global warming now and in the ancient past
From the National Oceanography Centre
The present rate of greenhouse carbon dioxide emissions through fossil fuel burning is higher than that associated with an ancient episode of severe global warming, according to new research. The findings are published online this week by the journal Nature Geoscience.
Around 55.9 million years ago, the Earth experienced a period of intense global warming known as the Palaeocene–Eocene Thermal Maximum (PETM), which lasted for around 170,000 years. During its main phase, average annual temperatures rose by around 5°C.
Scientists believe that the warming may have been initially triggered by an event such as the baking of organic-rich sediments by igneous activity that released the potent greenhouse gas, methane. This initial temperature increase warmed ocean bottom waters which allowed the break down of gas hydrates (clathrates), which are found under deep ocean sediments: this would have greatly amplified the initial warming by releasing even more vast volumes of methane. As the methane diffused from the seawater into the atmosphere it would have been oxidised to form carbon dioxide, another potent and longer-lived greenhouse gas.
Adam Charles and his PhD supervisor, Dr Ian Harding, both palaeoceanographers at the University of Southampton’s School of Ocean and Earth Science (SOES) based at the National Oceanography Centre, Southampton, co-authored the report. Dr Harding said: “The PETM has been seen by many as a natural test bed for understanding modern man-made global warming, despite it not being a perfect analogy. However, the total amount of carbon released during this climatic perturbation and its rate of release have been unclear.”
To help fill this gap in knowledge, the researchers measured carbon isotope ratios of marine organic matter preserved in sediments collected in Spitsbergen. The sedimentary section is important because it records the entirety of the PETM, from its initiation to through the recovery period, and as such is the most complete record of the warming event so far known in high northern latitudes.
Based on their carbon isotope measurements and computer simulations of the Earth system, the researchers estimated that the rate of carbon emissions during the PETM peaked at between 300 million and 1,700 million metric tonnes per year, which is much slower than the present carbon emission rate.
“Our findings suggest that humankind may be causing atmospheric carbon dioxide to increase at rates never previously seen on Earth, which would suggest that current temperatures will potentially rise much faster than they did during the PETM,” concluded Dr Harding.
The authors of report published by Nature Geoscience are Ying Cui, Lee Kump, Christopher Junium, Aaron Diefendorf, Katherine Freeman and Nathan Urban (Pennsylvania State University), Andy Ridgwell (University of Bristol), and Adam Charles and Ian Harding (SOES). This research was supported by The Worldwide Universities Network, Pennsylvania State University, and the US National Science Foundation..
Cui, Y., Kump, L. R., Ridgwell, A. J., Charles, A. J., Junium, C. K., Diefendorf, A. F., Freeman, K. H., Urban, N. M. & Harding, I. C. Slow release of fossil carbon during the Palaeocene–Eocene Thermal Maximum. Nature Geoscience (Published online, 5 June 2011). DOI: 10.1038/NGEO1179
So no runaway warming then. 🙂
I say boo hoo to their predictions. Just see where the IPCC thought we would be now compared with observations. They are obsessed with co2 damn it!
http://wattsupwiththat.com/2011/06/09/comparing-ipcc-1990-predictions-with-2011-data/
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“The present rate of greenhouse carbon dioxide emissions through fossil fuel burning is higher than that associated with an ancient episode of severe global warming…”
That’s because there never has been such an association. Furthermore, there is ample evidence the there was no significant CO2 rise associated with the PETM.
The “tightly correlated” CO2 concentrations and temperatures of the Pleistocene are clearly examples of a climate-driven carbon cycle. The loosely defined Phanerozoic correlation is based on Royer et al, 2004. Veizer’s and Shaviv’s reply to Royer et al., 2004 pointed out that this covariance was obtained through a pH adjustment to oxygen isotope data; which brought the temperatures into line with the paleo-CO2 levels. The pH adjustment was derived from CO2. So, Royer used CO2 to calibrate temperatures to CO2…
What I have learned from reading the article and the comments is that the journal “Nature Geoscience” is either a shill for global warming or edited by people whose stupidity is surpassed only by their lack of commonsense. How they manage to drive to work is beyond comprehension. The pro-AGW claims made in the article defy many points of rock solid commonsense, points that are beyond question.
Pompous Git. You are correct. The extinctions are associated with
oceanic oxygen deprivation. I am aware many believe oceanic currents played a great part in the extinctions, but the literature I have read do not credit the current patterns directly with the lack of oxygen, but rather with the distribution of heat. But I can be corrected.
This study puts the PETM CO2 level at about 4,500 ppm.
So start at 500 ppm, the average range of CO2 immediately before the event.
500 ppm
1000 ppm —-> 1 doubling
2000 ppm —-> 2 doublings
4000 ppm —-> 3 doublings
4500 ppm —> 3.25 doublings
And 3.25 doublings —> resulted in —–> +5.0C
then the CO2 sensitivity is ——-> 1.5C per doubling ——> it will take us 1000 years to get to 2 doublings so there is nothing to worry about until then.
Climate scientists just can’t do this simple math. It just does not occur to them that they should do it. If you are a scientist doing a PETM disaster movie/study, don’t you think you check the sensitivity results of your numbers.
What temperature does CO2 at around 0.06% of the atmosphere by weight with a specific heat of less than 1 gram/K have to be to heat the atmosphere by 1 K ? Surely it must be way hotter to radiate sufficient energy to do that – or have the IPCC disproved Thermodynamics ??
I can’t get my head around that one – help.
As we saw a few posts previously, the AGW community regards geology as hostile territory and generally avoids it, refusing en masse for instance to accept invitation to attend a conference on climate change from a geological perspective. They do not have a geological perspective, preferring an intimidatory silence concerning deep time and the geological record as a whole, within which AGW fares no better than a snowball in hell.
http://wattsupwiththat.com/2011/06/08/alarmists-refuse-to-take-on-skeptical-geologists/
However from time to time in a carefully orchestrated way, AGW warriors will make calculated forays into palaeo climate. Such forays focus narrowly on a limited time period or geographic location, for instance some transition or short period of some sort, from which, with the help of their usual toolbox of tricks, an AGW story can be crafted.
Here they focus on the PETM, a period of 170,000 years, 56 Myrs ago, during which global temperatures increase 5C. One predictable component immediately appears – this warming was caused by atmospheric carbon (the only politically acceptable reason for any climate change) – although it is methane, not CO2. (But hang on – we are told CAGW is irreversible, then how come this period lasts only 170,000 years? Carbon atoms stay in the atmosphere till the end of the universe and beyond, we are told. WUWT?).
A little later a surprising statement is made: “However, the total amount of carbon released during this climatic perturbation and its rate of release have been unclear.” “Released during this period?” So they implicitly concede that temperature increase causes carbon release, rather than the reverse? Or perhaps its a palindromic reversible causality?
A few lines later a trademark smoke-and-mirrors conjuring trick is performed – methane morphs into CO2, seamlessly and without any explanation. One moment the carbon being discussed is methane, the next its CO2? Nice move – a careful observer would see a lump moving down the conjurer’s trouser-leg.
As Doug Proctor (June 9, 2011 at 9:22 am) pointed out from the wikipedia entry on the PETM, the warming preceded the atmospheric CO2 increase by 3000 years. So it takes all the conjuring skills of an AGW professional to spin this as a CAGW story. You have to admire their brazen courage for having a go anyway.
So many “ifs”. I’m reminded of the old, old saying…
‘If a frog had wings, he wouldn’t bust his behind every time he hopped.’
Don Horne
Grumpy Old Man says: “‘Scientists believe that warming MAY’, ‘our findings suggest’. Is there any hard science out there?”
May and suggest and the like are permissible weasel words, standard fare in scientific parlance. I’ve used them often. Hard science is not determined a lack of equivocal statements, but by the presence of truthful ones. However, use of the phrase “Scientists believe x” (instead of “Some scientists believe x”) is clearly propaganda, since it gives the erroneous impression that all scientists believe x, which is rarely an accurate statement, and is not inconsistent with an attempt to lie like a Chicago politician.
““Our findings suggest that humankind may be causing atmospheric carbon dioxide to increase at rates never previously seen on Earth,”
This is only true if you buy into the fabricated assumption that CO2 was consistently low during the last 200 years, until the 1950s when it began to rise. If you look a direct CO2 chemical bottle data (a la Erst Beck – 80,000 direct data points), you find that CO2 can rise much more rapidly than it is today and has done so during three periods of the last 200 years. Myopic science is not science; specifically blinding oneself is not a way to see clearly.
Congratulations to whomever managed to get a one-year resolution in data coming from 55.9 million years ago. Mark Twain will be proud of them!
And with the clathrate release was there a drop of atmospheric O2 levels as the methane oxidised? No there was not which leads to thinking that the clathrate release never happened.
Methane readily oxidises in the atmosphere but uses a lot of oxygen, work it out the products are CO2 and H2O.
The good point made in the post is the 1 year resolution after 55Ma which is incredible.
More scary campfire tales for children. The words ‘might’, ‘may’ and ‘could’ feature too heavily in thos to allow iot to be taken seriously be sentient adults.
\”Our findings suggest that humankind may be causing atmospheric carbon dioxide to increase at rates never previously seen on Earth\”
Although human CO2 emissions are higher than ever before, the recent growth rate of atmospheric CO2 (ppm) seems rather anemic in context to the above claim of these researchers. The article at this link shows ppm growth rates that are pretty modest: http://www.c3headlines.com/2011/06/the-leftliberal-bizarro-anti-science-hyperbole-continues-lefty-blogger-romm-calls-co2-growth-super-e.html
“Our findings suggest that humankind may be causing atmospheric carbon dioxide to increase at rates never previously seen on Earth”
Although human CO2 emissions are higher than ever before, the recent growth rate of atmospheric CO2 (ppm) seems rather anemic in context to the above claim of these researchers. The article I read at this link shows ppm growth rates that are pretty modest: http://www.c3headlines.com/2011/06/the-leftliberal-bizarro-anti-science-hyperbole-continues-lefty-blogger-romm-calls-co2-growth-super-e.html
“Scientists believe …” So much of that going around. So very liltle of “Scientiists know.” Speculation by a scientist is no better than speculation by a politician or a musician. Yet, that “Scientists believe” (or alternatively “The study suggests”) intro gets ’em every time. Selective measurements followed by untethered projection does not make the product science – even if the people doing it have a degree and consider themselves scientists. A scientist is only a scientist to the degree that his work is science – which may still sometimes in error. The rest of the time, the’yre human beings playing scientists like what we see in this article.
It is highly unlikely that 56 million year old ocean sediments give you the ability to measure the change in CO2 over a span a short as a few hundred years. Calculate the increase in temperature from morning to night. Compare this to the average temperature from one year to the next. You would conclude that daily temperatures are changing much more rapidly than annual temperatures.
Same for CO2. CO2 levels are changing much more quickly over a span of 100 years than averaged over a million years. This tells us nothing about CO2. Rather it tells us about the nature of averages. Over a longer period of time an average will show less fluctuation than over a shorter period of time. No matter if it is CO2 or anything else you wish to study.
Faulty math = faulty conclusion.
This would be a fine sceptical paper if only its conclusion wasn’t so wishfully predetermined. I would suggest this alternative, more logical, final conclusion:
“Our findings suggest that humankind may be causing atmospheric carbon dioxide to increase at rates never previously seen on Earth, which would suggest that the current global cooling contradicts the AGW hypothesis.”
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dp says:
June 9, 2011 at 10:10 am
Deccan Traps at play?
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More likely the changes of the Tethys sea. The movement of the Indian sub-continent also played a role, along with the growth of the Himalayas that it caused. Its sad, that these propagandists in lab coats can’t counter the known explanations, so they just ignore them as if they never existed.
Nice try Dr. Harding, except for one thing. YOU’RE WRONG!
Instead of micro-analyzing a pixel of data, how about looking at the big PALEOTEMP and GEOCARB picture of Scotese and Berner. We are only 25% off the bottom of the historical temperature range and about 94% below the high CO2 concentration over the last 6E8 years. So, what’s the problem?
I don’t buy this rate of change stuff, or second derivative stuff, or the fabrication of FrankenGraphs like Mann’s Hockey Stick, or computer projections based on woefully inadequate modelling and questionable initial conditions, just because the historical data doesn’t fit the alarmist view.
To the global warming consensus crowd, I have just one question: explain why the ice core data shows the CO2 increases occur about 800 years AFTER the temperature increases? Answers anyone?
Most of the authors are from Penn State, where Mann helped build his kingdom on his silly graph.
I would love to know how many studies can be tracked back to Hansen, Mann and Jones and their disciples.
‘This may be off topic, but DCC, June 9, 10.26 referenced to a chart with CO2 and temperaure:
http://www.geocraft.com/WVFossils/PageMill_Images/image277.gif
What seems interesting to me was a 1.5 million year temperature cycle which appears in the chart.
What could cause that?