From the National Science Foundation, another bit of Speculative Science™ note the caveat in bold, which is all they need for a headline that screams certainty:
This sudden release of gases into the atmosphere may have created intense global warming, and acidification of the oceans, which ultimately killed off thousands of plant and animal species.
See below for the alternate scenario based on the same press release.
Press Release 13-046
Before Dinosaurs’ Era, Volcanic Eruptions Triggered Mass Extinction
Increase in atmospheric carbon dioxide, global warming, ocean acidification killed 76 percent of species on Earth
 Back to the future? Ancient rocks in Hartford Basin, Conn., offer a look into geologic time.
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March 21, 2013
More than 200 million years ago, a massive extinction decimated 76 percent of marine and terrestrial species, marking the end of the Triassic period and the onset of the Jurassic.
The event cleared the way for dinosaurs to dominate Earth for the next 135 million years, taking over ecological niches formerly occupied by other marine and terrestrial species.
It’s not clear what caused the end-Triassic extinction, although most scientists agree on a likely scenario.
Over a relatively short time period, massive volcanic eruptions from a large region known as the Central Atlantic Magmatic Province (CAMP) spewed forth huge amounts of lava and gas, including carbon dioxide, sulfur and methane.
This sudden release of gases into the atmosphere may have created intense global warming, and acidification of the oceans, which ultimately killed off thousands of plant and animal species.
Now, researchers at MIT, Columbia University and other institutions have determined that these eruptions occurred precisely when the extinction began, providing strong evidence that volcanic activity did indeed trigger the end-Triassic extinction.
Results of the research, funded by the National Science Foundation (NSF), are published this week in the journal Science.
“These scientists have come close to confirming something we had only guessed at: that the mass extinction of this ancient time was indeed related to a series of volcanic eruptions,” says Lisa Boush, program director in NSF’s Division of Earth Sciences.
“The effort is also the result of the EARTHTIME initiative, an NSF-sponsored project that’s developing an improved geologic time scale for scientists to interpret Earth’s history.”
The scientists determined the age of basaltic lavas and other features found along the East Coast of the United States, as well as in Morocco–now-disparate regions that, 200 million years ago, were part of the supercontinent Pangaea.
The rift that ultimately separated these landmasses was also the site of CAMP’s volcanic activity.
Today, the geology of both regions includes igneous rocks from the CAMP eruptions as well as sedimentary rocks that accumulated in an enormous lake. The researchers used a combination of techniques to date the rocks and to pinpoint CAMP’s beginning and duration.
From its measurements, they reconstructed the region’s volcanic activity 201 million years ago, discovering that the eruption of magma–along with carbon dioxide, sulfur and methane–occurred in repeated bursts over a period of 40,000 years, a short span in geologic time.
“This extinction happened at a geological instant in time,” says Sam Bowring, a geologist at MIT. “There’s no question the extinction occurred at the same time as the first eruption.”
In addition to Bowring, the paper’s co-authors are Terrence Blackburn and Noah McLean of MIT; Paul Olsen and Dennis Kent of Columbia; John Puffer of Rutgers University; Greg McHone, an independent researcher from New Brunswick, N.J.; E. Troy Rasbury of Stony Brook University; and Mohammed Et-Touhami of the Université Mohammed Premier (Mohammed Premier University) Oujda, Morocco.
Blackburn is the paper’s lead author.
More than a coincidence
The end-Triassic extinction is one of five major mass extinctions in the last 540 million years of Earth’s history.
For several of these events, scientists have noted that large igneous provinces, which provide evidence of widespread volcanic activity, arose at about the same time.
But, as Bowring points out, “just because they happen to approximately coincide doesn’t mean there’s cause and effect.”
For example, while massive lava flows overlapped with the extinction that wiped out the dinosaurs, scientists have linked that extinction to an asteroid collision.
“If you want to make the case that an eruption caused an extinction, you have to be able to show at the highest possible precision that the eruption and the extinction occurred at exactly the same time,” Bowring says.
For the time of the end-Triassic, Bowring says that researchers have dated volcanic activity to right around the time fossils disappear from the geologic record, providing evidence that CAMP may have triggered the extinction.
But these estimates have a margin of error of one to two million years. “A million years is forever when you’re trying to make that link,” Bowring says.
For example, it’s thought that CAMP emitted a total of more than two million cubic kilometers of lava.
If that amount of lava were spewed over a period of one to two million years, it wouldn’t have the same effect as if it were emitted over tens of thousands of years.
“The timescale over which the eruption occurred has a big effect,” Bowring says.
Tilting toward extinction
To determine how long the volcanic eruptions lasted, the group combined two dating techniques: astrochronology and geochronology.
The former is a technique that links sedimentary layers in rocks to changes in the tilt of the Earth.
For decades, scientists have observed that the Earth’s orientation changes in regular cycles as a result of gravitational forces exerted by neighboring planets.
The Earth’s axis tilts at regular cycles, returning to its original tilt every 26,000 years. Such orbital variations change the amount of solar radiation reaching the Earth’s surface, which in turn has an effect on the planet’s climate, known as Milankovich cycles.
This cyclical change in climate can be seen in the types of sediments deposited in the Earth’s crust.
Scientists can determine a rock’s age by first identifying cyclical variations in deposition of sediments in quiet bodies of water, such as deep oceans or large lakes.
A cycle of sediment corresponds with a cycle of the Earth’s tilt, established as a known period of years.
By seeing where a rock lies in those sedimentary layers, scientists can get a good idea of how old it is. To obtain precise estimates, researchers have developed mathematical models to determine the Earth’s tilt over millions of years.
Bowring says the technique is good for directly dating rocks up to 35 million years old, but beyond that, it’s unclear how reliable the technique is.
He and colleagues used astrochronology to estimate the age of the sedimentary rocks, then tested those estimates against high-precision dates from 200-million-year-old rocks in North America and Morocco.
The geologists broke apart rock samples to isolate tiny crystals known as zircons, which they analyzed to determine the ratio of uranium to lead.
The technique enabled the team to date the rocks to within approximately 30,000 years–a precise measurement in geologic terms.
Taken together, the geochronology and astrochronology techniques gave the geologists precise estimates for the onset of volcanism 200 million years ago.
The techniques revealed three bursts of magmatic activity over 40,000 years–a short period of time during which massive amounts of carbon dioxide and other gas emissions may have drastically altered Earth’s climate.
While the evidence is the strongest thus far for linking volcanic activity with the end-Triassic extinction, Bowring says that more work can be done.
“The CAMP province extends from Nova Scotia all the way to Brazil and West Africa,” he says. “I’m dying to know whether those are exactly the same age.”
-NSF-
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I can play this game, using their paragraph:
This sudden release of gases into the atmosphere may have created intense global warming, and acidification of the oceans, which ultimately killed off thousands of plant and animal species.
Change a couple of words, and we have a whole new plausible scenario:
This sudden release of ash, soot, and stratospheric aerosols (like SO2) into the atmosphere may have created intense global cooling, due to blocked sunlight, which ultimately killed off thousands of plant and animal species.
Is there also the possibility that the onset of volcanism 200 million years ago and the purported asteroid impact could have been connected?
This “sudden release of gas” from the National Science Foundation shows that in the game of climate, volcanos are a very versatile wild card or joker. If we have recent cooling contrary to warming predictions, a volcano can be blamed. If we have a past mass extinction and the need arises to contrive a way to show that this was caused by CO2, then volcanos feature again!
phlogiston says:
March 23, 2013 at 12:30 am
But, where are the “excessive” and “massive” volcanoes since 1997-1998? Since Pinatubo actually?
Those volcanoes had a measurable and credible impact on the world’s temperature. But only for a 18 month period. After 2 years, there is NO impact.
We have been flat-lining climate deniers since 1996. And there have been no exceptional or even noteworthy or newsworthy volcanoes or high-volcanic regions in that entire time. Eruptions? A few. None have made the evening news but for the Iceland eruption … and that slowed within 2 weeks. 1 day of air traffice impact.
For all you pedants out there: It appears that your insistence on the word meaning “to decrease by 10%” is a modern definition. see: http://english.stackexchange.com/questions/11070/decimate-has-it-been-used-in-the-classic-sense-in-modern-writing
Susan Corwin says: March 22, 2013 at 2:03 pm The trigger?
You beat me to this point. Time zone problem. Yes indeed, what caused the atypical motion of the CAMP estimate of 2 million cubic km of lava?
At present, there is a crust over most of the Earth that is at the temperature of the water or air above it. If you open a rift and spew forth that quantity of hot rock, you will change the geothermal gradient in its vicinity by an enormous amount. This is prime material for modellers. In the time given, how much temperature change would be caused by the efflux of these hot rocks from below the surface, to the surface? Would this cool the Earth? In the gross sense, yes, because it would speed the flow of energy from under the crust towards the atmosphere. It’s a heat release mechanism. Therefore, one might expect it to heat the atmosphere on its way out, although other effects might add to, or subtract from the equation as mentioned by several above. We simply don’t know, because the data are inadequate.
(I do wish for an article that does not mention CO2.)
Peter Miller says:
In passing, correct that zircon dating gives the age of crystallisation, not the age of sedimentation, and they are seldom the same. A little related, I have analysed a long drill hole from Central Australia where so-called igneous rocks, Tennant Creek ‘porphyroids’ interlayered with sedimentary rocks, have a chemical composition that is unable to differentiate to a high degree of significance between porphyroid and sediment by either whole rock analysis or trace elements – with the exception of a small difference with copper. The inference is that one formed from the other.
Aging a zircon only tells when that crystal formed in the igneous rock not the age of the sedimentary rock it was eventually found.
Fossils are not the best dating method because of their rarity, or at least the signature species needed for dating. Less than 1% of animal or plant life is found fossilized due to the complex requirements of fossilization and where the animal died. Land animals can be predated after death and bones scattered, in fact a good fossil is as rare as hens teeth.
Why all the emphasis on CO2 emitted from volcanoes?
Sulphur Dioxide is the real killer.
Reacts with water to form sulphuric acid- now that really WILL lead to ocean acidification.
In the atmosphere it acts as a precursor to particulates in the atmosphere- leading to abrupt cooling (nuclear winter anyone?).
Finally exposure to 100 parts of sulphur dioxide per million parts of air (100 ppm) is considered immediately dangerous to life and health.
Back in 2002 NASA came to a much different conclusion on the Triassic extinction using similar error margins in time. They found evidence of a large asteroid.
http://science.nasa.gov/science-news/science-at-nasa/2002/28jan_extinction/
“These scientists have come close to confirming something we had only guessed at: that the mass extinction of this ancient time was indeed related to a series of volcanic eruptions,” says Lisa Boush, program director in NSF’s Division of Earth Sciences.
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“These scientists have been unable to confirm something we have resorted to guessing at: that the mass extinction of this ancient time was indeed related to a series of volcanic eruptions,” says Lisa Boush, program director in NSF’s Division of Earth Sciences.
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Apparently science is like horseshoes. Points for coming close.
If we have some ham, we “may have” ham and eggs today, if we have some eggs.
RACookPE1978
I agree entirely that volcanoes are an utterly inadequate explanation / excuse for the end of the recent warming and the current stasis. I was trying to be sarcastic. This is natural fluctuation of global temperature for which the “reason” is beyond our current understanding. Honest acknowledgement of the current stasis does indeed falsify the CAGW hypothesis which should now be rejected.
Bill Illis
Are magma plume eruptions the same thing as “flood basalt” events?
The coincidence of high levels of intense volcanic activity with extinction events is, of itself and interesting one. The length and physical magnitude of the events is something that climatologists do not take proper account of when projecting the catastrophic impacts.
The press release seems to assume that the only impact of large-scale volcanic activity on climate is through the release of greenhouse gases, causing rapid warming and ocean acidification. Such impacts are trivial compared with other effects. We know that the Mount Pinatubo eruption caused a short-term drop in global temperatures. That eruption was tiny in both magnitude and time compared with the scale of the volcanic activity talked about in the paper. There could have been large drops in global temperatures for decades or centuries at a time, Combined with the lack of sunlight, plant plant growth could have been significantly reduced. Further, the gases emitted could have poisoned the atmosphere.
It has one sense, the one garymount described. It was the fate of any Roman legion that performed with gross incompetence in the face of the enemy and that example is the source of the term. It has accreted, through careless application, the two nonsenses you describe.
You guys, come on! You all know that flatulating herbivores increased atmospheric methane which in turn became CO2 over time which being all powerful increased both asteroid strikes and volcanic activity while simultaneously acidifying the ocean and overheating the planet killing off the very herbivores that spewed the powerful Greenhouse Gas in the first place, it’s the Karma Law that precautionary principled people know not to ignore due to the ever present repercussion amplification that always accompanies climate disruptions.
…… (/sarc) …..
D. J. Hawkins: In one sense garymount is correct. Having said that, his meaning is applicable if and only if one is referring to the specific practice of the Roman Army. In all other usages the modern sense applies.
I’ve been noticing a lot of criticism of wording like ‘may have’ and ‘could have’. The authors have a hypothesis that volcanoes increased GHGs which caused a major extinction. They find some rock dating evidence that corroborates, but does not prove it. How the hell else do they say it?
Also, they talk about increased volcanic activity over thousands of years. Wouldn’t the sulfates from each individual volcano wash out of the atmosphere rather quickly while the CO2 accumulated?
@ur momisugly Canman: The authors are not talking about single volcanoes. The Central Atlantic Magmatic Province (CAMP) is the largest (in area) continental volcanic province (approx. 11 million sq km) found to date. The CAMP was active for about 1-2 million years and ejected into the atmosphere copious quantities of CO2, SO2, and a host of other acidic gasses and aerosols. This eruptive phase from all available evidence suggests that there was nearly continuous eruptive activity. I doubt that the sulfates and aerosols washed out of the atmosphere quickly.
One day, hopefully soon, scientists will become aware of the Gravity Theory of Mass Extinction. This theory posits a common cause for every mass extinction; changes of the Earth’s gravitational field due to the offsetting of the Earth’s core elements.
http://www.dinoextinct.com/page13.pdf
It explains why flood basalt volcanism occurs with every mass extinction event.
It explains why a rapid, massive drop in sea level coincides with every mass extinction. This is why methane is released from the sea bottom in great quantity causing an isotopic excursion.
The complete extinction of the crurotarsi at the T-J mass extinction while dinosaurs were spared can readily be explained by the splayed-leg (and hip) structure of the crurotarsi which resulted in a big disadvantage when surface gravity increased. The massive jaw structure of the conodonts similarly became a big impediment that doomed them to extinction. Likewise, the ammonites almost became extinct at this time as well as other calcium-rich shelled sea life.
What of the Deccan Traps and the Columbia Plateau Basalts? Where oh where are the mass acidifications that may have happened? Whoops! They must have forgotten to google. What horridly agenda-driven tripe.
@ur momisugly Mike Bromley the Canucklehead etc.: To answer your question about the Deccan Traps and the Columbia River Basalts (CRB). Look at the areas and volumes involved. The CRB covered approx 164K sq km(174K cu km) and the Deccan Traps covered about 500K sq km (512K cu km). Contrast this with the area of the CAMP. The CAMP covers approx 11,000,000 sq km!!!!and has an estimated volume of approx 2.4M cu km That is why you had an extinction event. It has been suggested that emplacement of the Deccan Traps contributed to the demise of the dinosaurs at the end of the Cretaceous.
Canman says:
March 23, 2013 at 2:32 pm
Yup. If you want to argue that said volcanic activity “may have” caused cooling instead, a comparison of the evidence on both sides would be useful for advancing that argument. In the long run, it looks really silly for people to mock scientists because they think and talk like scientists; because they are willing to report interesting results, but are not willing to pretend to certainty where there is none. All theories are open to reinterperatation when faced with new data. So, actual, absolute scientific certainty is so rare as to be nearly non-existent, and the language of science reflects this.
greymouser70 says:
March 23, 2013 at 4:54 pm
This would elevate the levels of CO2, sulfates, and aerosols far above the levels expected from a single large eruption. However, since the sulfates and aerosols leave the atmosphere much more quickly, their eventual equilibrium concentration would not be elevated nearly as much as that of CO2.
Staten-John says:
March 23, 2013 at 8:08 pm
There is not enough aluminum foil in the world to properly cover one’s head while attempting to read this.
JazzyT says:
The sulfates and aerosols probably did precipitate out of the atmosphere relatively quickly. However I would venture to guess that the sulfates fell out as acid rain (H2SO4, H2SO3 and others) and in much greater quantities than we have ever seen in the present.
@JazzyT,
Without using aluminum foil, please explain why the crurotarsi became extinct at the T-J boundary but the dinosaurs did not.
greymouser70 says:
March 23, 2013 at 11:20 am
Ah so; there are precise rules for sloppy usage.
Pray tell, greymouser70, when did the “modern sense” enter into the popular lexicon? Maybe it was during the “Dark Ages”, eh? 87)
~
K’UNG-FU-TZU said (around 500 BC):
Nevertheless, Incorrect or not, popular usage will prevail with the masses, and some words will change meaning over time, although a few educated persons will resist what they see as the disintegration of proper discourse, with the consequences noted by the Chinese sage.
Because language is the human asset that has allowed our species to prosper and human civilization to advance, some of us appreciate its power, the precision with which it can be used, and the benefits that accrue to our species when language is used with the greatest skill in the pursuit of the truth.
And it is only the truth that will save us.
Somebody – not Abe Lincoln – said that you can’t fool all of the people all of the time. Unfortunately – in the recent past, at the very least – it’s only been necessary to fool most of the people most of the time, as we have seen. Even when the truth comes out later, the deal allowed by the lie is done, a fait accompli, and the masses quickly pick up the (current) MSM meme that “we weren’t really fooled.”
And so it goes.