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.
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If in fact Pangaea was split up, what was the effect on the earth’s position to and journey around the sun?
Would not a slight change is the orbit have a profound effect on the climate?
But that wouldn’t be the ‘devine’ spin if they wrote it your way.
Myron Mesecke says:
March 22, 2013 at 10:32 am
“But that wouldn’t be the ‘devine’ spin if they wrote it your way.”
In climatism, the trend is your friend. Wait five years and the spin might go the other way.
Hey you need grant money- just say the magic words” “Carbon” ” Acidification”. “Global Warming”.
and presto changeo -funds magically appear…
Just a little P.ositive R.einforcement goes along way in public relations.
The NSF is rebranding itself as the NSDF, the National Science Drama Foundation. This particular press release makes one wonder if we are in “sweeps week.”
Mt Tambora = Global cooling
Mt Pinatubo = Global cooling
I think Anthony’s “spin” may be closer to the truth.
Siberian Traps, anyone? Several hundred thousand years of huge crevasse volcanoes spewing magma and a noxious mix of CO2 and sulfur dioxide? “Pink water”?
Any of that ring any bells?
And anyway, don’t complain. If it hadn’t happened, you wouldn’t exist.
“Press Release 13-046
Before Dinosaurs’ Era, Volcanic Eruptions Triggered Mass Extinction”
Typically shoddy headline writing, as there were plenty of Triassic dinosaurs, & they already dominated certain Late Triassic terrestrial environments. There were also Jurassic & Cretaceous environments which they didn’t dominate, depending upon what that term might mean.
Also, as Anthony notes, global cooling from aerosols & SO2 remains a plausible explanation. Nor can asteroid impact be ruled out. Although a crater from near the T/J EE in France is considered too small, there might have been other impacts at the same time, the craters of which haven’t been found or have been covered by sea floor spreading. Admittedly the latter possibility is speculative & would require more supporting evidence than has emerged to date, AFAIK.
Rifting alone & continents separating would naturally affect species locally.
All science writing requires the use of the conditional, because there are no absolutes in science. It is why even some of the media knew Gore’s statement that “the debate is over, the science is settled”, was wrong.
The deception about certainty is premeditated and exploited in extreme environmentalism; witness Paul Watson, co-founder of Greenpeace’s comment that “It doesn’t matter what is true, it only matters what people believe is true.” The choice to avoid the truth was proposed in climate science with Stephen Schneider’s comment to Discover magazine in 1989:
“On the one hand we are ethically bound to the scientific method, in effect promising to tell the truth, the whole truth, and nothing but, which means that we must include all the doubts, caveats, ifs and buts. On the other hand, we are not just scientists, but human beings as well. And like most people, wed like to see the world a better place, which in this context translates into our working to reduce the risk of potentially disastrous climate change. To do that we have to get some broad-based support, to capture the publics imagination. That, of course, entails getting loads of media coverage. So we have to offer up scary scenarios, make simplified, dramatic statements, and make little mention of any doubts we might have. This double ethical bind which we frequently find ourselves in cannot be solved by any formula. Each of us has to decide what the right balance is between being effective and being honest. I hope that means being both.”
There is no decision. Since when was there a need for a balance between the truth and a lie? For Schneider it is when the end justifies the means. But science can only function when it is amoral and apolitical and must constantly strive to be both.
I thought that the standard was that a large volcanic eruption leads to cooling. This is the continued claim and is the the reason given for any cooling ‘not in the models’. Indeed we are told that a large volcanic eruption would lead to the equivalent of a ‘nuclear winter’. 1816 – was called “The year without a summer” and that is blamed on the eruption of Mt Tambora.
So are they in a ‘warm snow’ mode with hot vs cold volcanic effects?
Again, when I read these sorts of things, I become less and less averse to humankind having a hand in it’s own extinction event. Go ahead, strip the climate security blanket (CO2) from the 1/2 precession-cycle old late Holocene atmosphere and perhaps, in so doing, remove the only supposed speedbump to the next ice age. The next iteration of the genus Homo may come to thank you for it.
Just imagine, for a moment, continuation of the species Mann……….
That makes two of the five major extinctions related to large magma plume eruptions.
Volcanic cooling, fires and poisonous gases from unbelievably large eruptive events lasting for 40,000 years (Jurassic) to 3 million years (Permian).
Why is it so hard for the scientists to just state the obvious.
When I was a kid, and very much into Dinosaurs, I read that the prevailing ideas about volcanic eruptions causing extinction would be due to ash, etc. in the air blocking sunlight, causing not warming or cooling, but ruining plant growth… and so everything on up the food chain suffered and died from starvation.
It makes a lot more sense to me than thousands of years of activity slowly cooking or freezing things away or whatever else. How many plants can survive more than a few months with insufficient light?
One indicator of which side is winning the CAGW debate is the level of public derision when magic incantations are uttered.
Puzzling to me why announcements like the subject of this article don’t get a rougher ride, but in the long run, truth will out. We wait.
National Science Foundation = NSF, Non Sufficient Funds
They are morally bankrupt.
Dating zircons in sediments will not tell you the age of the sediment. It tells you the age when the zircon crystallised in its original igneous rock.
As for the rest of it, they looked like Mannian dating techniques to me.
The last paragraph above shows that any connection in the above with global warming is the most tenuous, and of course political rather than scientific, speculation. But much worse, the description of the Earth’s “tilt” is described carelessly and incompetently (the 26,000 year period is just the precession period, and changes in Earth’s obliquity, or axial tilt, within that period would have no effect whatsoever upon the amount of solar energy reaching any part of the Earth, over a year’s time). Worst of all, the Earth’s spin axis has been in precessional motion around the current ecliptic north pole for only 17,000 years, substantially less than even one precession period (see the simplest, definitive evidence in my 2009 blog post, Challenge to Science III: The “gods”, the Design, and Man), when the “Great Design of the ‘gods'”, as I call it, was made. The current paradigm, of undirected evolution of the Earth’s surface, is obsolete and incompetent, as are all of the hyped “discoveries” now, like the above.
… that is, Challenge to Science III: The “gods”, the Design, and Man)
Apart from the ash and sulfate aerosols, extreme volcanism should also release enormous amounts of hydrochloric acid (HCl) and sulfuric acid (H2SO4), with smaller but still large amounts of HF, HBr, and HI. Most of the acid vapors would stay in the troposphere.
These mineral acids would deposit as extremely acid rain, probably overwhelm the carbonate/borate buffer in the upper layers of the ocean, and cause really extreme acidification. Something similar would happen on land. One would guess collapse of the food chain, because the calcareous diatoms would not survive. Nor would most land vegetation.
Eventually, the marine acid would get buffered away by carbonate runoff from the land. Calcareous and siliceous diatoms that may have survived in cryptic locations would repopulate after the marine pH became greater than about 6 (marine pH is typically about 8.1 these days, and probably then, too).
The combination of aerosol cooling, as Anthony has it, plus the huge pulse of mineral acids, are all one needs for a global extinction event. The same consequences (ash + acid) are released by a large bolide impact.
Released CO2 and methane are more likely small actors in the scenario, with negligible impact. The early Triassic already had about 1000 ppm CO2 in the atmosphere. The end Triassic about 3000 ppm. Given CO2 saturation, the change in forcing is of small relative importance. The CO2 may actually help ameliorate the bad conditions by accelerating the solubility of surface carbonates, for runoff into the oceans.
I remember reading an estimate that, after the KT bolide impact, which had similar consequences, Earth ecology returned to normal by 1 million years. That’s fast by biogeological standards, but of course was of small comfort to the killed and the extinct.
For Old Weird Harold
http://youtu.be/lPruGs4IyK4
It’s funny that when a big volcano goes off today scientists talk of tropospheric cooling and stratospheric warming. 40,000 years of violent spewing of aerosols into the atmosphere is no chump change for land animals.
A small amount of aerosols and sulphur dioxide is enough to stop the current global warming in the warmists view.
So at the end of the Triassic we had both warming (CO2, methane) and cooling (aerosols and sulphur dioxide). The cooling elements were much, much greater than at present.
Modelling should break out how much effect each hasI guess. (Right.)
Science by press release – the new norm!