Claim: Extreme Global Warming caused mass extintion event 252 million years ago

From CAGE – CENTER FOR ARCTIC GAS HYDRATE, CLIMATE AND ENVIRONMENT and the unquestionable certainty about the past department:

Plot of extinction intensity (percentage of genera that are present in each interval of time but do not exist in the following interval) vs time in the past for marine genera.[1] Geological periods are annotated (by abbreviation and colour) above. The Permian–Triassic extinction event is the most significant event for marine genera, with just over 50% (according to this source) failing to survive.
Plot of extinction intensity (percentage of genera that are present in each interval of time but do not exist in the following interval) vs time in the past for marine genera.[1] Geological periods are annotated (by abbreviation and colour) above. The Permian–Triassic extinction event is the most significant event for marine genera, with just over 50% (according to this source) failing to survive.

Extreme global warming  caused a severe mass extinction of life on Earth 252 million years ago. It took life up to 9 million years to recover. New study finds clues in the Arctic as to why this recovery took so long.

Arctic gives clues on worst mass extinction of life

96 percent of marine species, and 70 percent of terrestrial life died off in the Permian-Triassic extinction event, as geologists know it. It is also known as The Great Dying Event for obvious reasons.

“The mass extinction was likely triggered by a explosive event of volcanic eruptions in what is now Siberia. These eruptions lasted for a million years and emitted enormous amounts of volatiles, such as carbon dioxide and methane, which made our planet unbearably hot.” says Jochen Knies, researcher at CAGE.

Life took an extraordinary long time to recover from this extinction, from 5 to 9 million years. Why recovery was so delayed, has remained a mystery.

Clues are in the Arctic

Knies is the co-author of a study that took to the Arctic to look for clues as to what limited return of life to world´s oceans. The results of the study illustrate potential long-term impacts on marine ecosystems in response to global warming.

“What used to be the northwestern continental margin of the supercontinent Pangaea is now Canadian High Arctic. There we found evidence in geological records for a significant nutrient gap during this period. This means that global oceans were severely poor in nutrients such as nitrogen,” says Knies.

This nutrient gap is most likely the result of extremely high ocean surface temperatures in the aftermath of the extinction.

Be cool stay alive

Our oceans are not a single body of water. They are comprised of layers and boundaries based on temperature (thermocline) and nutrients (nutricline) among others.

“The high temperatures caused deepening of the thermocline and nutricline in the ocean so that upwelling of nutrients from the bottom to the surface of ocean ceased. With that the marine algae productivity was stalled,” according to Knies.

And without algae, which are the base of the food chain, the life in the ocean did not thrive.

Once oceans finally started cooling 6-7 million years after the extinction, nutrient rich waters returned.

“The boundaries that kept the nutrients from reaching the surface were weakened and the ocean waters were mixed. This caused the upwelling of nutrients, resuscitating the oceans, and leading to an explosion of life. The ecosystem voids created by the worst mass extinction in Earth history were finally filled.” states Jochen Knies

In many ways the Permian-Triassic mass extinction reset the evolution of life, and paved the way for evolution of dinosaurs. They, in turn, died off in another mass extinction 66 million years ago. Today some scientists argue that we are facing a new mass extinction period, mostly caused by human activities.


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August 24, 2016 10:51 am

The P-T mass extinction event has not yet been fully explained, but global warming is not the primary cause, despite the Siberian Traps.

Eustace Cranch
Reply to  Gabro
August 24, 2016 10:56 am

It would be nice if you could point us somewhere that backs up your claims. Without that, it’s just words.

Reply to  Eustace Cranch
August 24, 2016 11:21 am

Whereas, making the claim that extreme global warming was the cause is absolute, proven fact?

Reply to  Eustace Cranch
August 24, 2016 11:49 am

This reconstruction found the end Permian a degree or two warmer than other hot house intervals of the Phanerozoic Eon:
Other warm phases lasted longer without mass extinction events. The brief but almost as hot PETM (at the boundary between the Paleocene and Eocene Epochs of our current Cenozoic Era) produced no significant increase in extinctions.

george e. smith
Reply to  Eustace Cranch
August 24, 2016 11:52 am

So starting 542 million years ago, we have witnessed the extinction of Curium, Oxygen, Sulfur, Deuterium, Carbon, Phosphorous, Tracium, Judium, Potassium, Pangolium, and Nitrogen.
But it seems that most of those have recovered nicely. Do we really miss having Tracium Judium and Pangolium anymore ??
I don’t think we do.

Reply to  Eustace Cranch
August 24, 2016 12:01 pm

Indeed, the Ordovician MEE was associated with an ice age, despite CO2 levels of 4000 to 7000 ppm at that time.

Bryan A
Reply to  Eustace Cranch
August 24, 2016 12:29 pm

Oh I dunno, Pangolium stew with chunks of Judium and a trace of Tracium for flavor sounds delicious

William Astley
Reply to  Eustace Cranch
August 24, 2016 12:37 pm

Atmospheric CO2 was estimated to have increased from 1000 ppm to 1700 ppm during the P-T mass extinction. Subsequent to the P-T event atmospheric CO2 has been as high as 2500 ppm with no warming and no extinction.
If you look at the geological record planetary temperature does not correlate with the level CO2 in the atmosphere.
There are periods of millions and millions of years when atmospheric CO2 is high and the planet is cold and vice versa. This is one of couple of dozen different observations and analysis results that confirm the IPCC estimated warming for a doubling atmospheric CO2 (3C with feedbacks) is too high by a factor of at least 6 (is less than 0.5C).

Robert W Turner
Reply to  Eustace Cranch
August 24, 2016 12:44 pm

With this hypothesis they demonstrate that they have an elementary misunderstanding about the oceans and climate, and probably philosophy in general.
The warm surface temperatures are the result of the slow down or cessation of vertical overturning marine waters, which also is the reason for nutrient-deficient water in the photic zone. Phytoplankton do quite well in any temperature of water found naturally on the planet, as long as there are nutrients and sunlight.
This is grade school stuff, it –the corruption of science– is worse than we thought.

Reply to  Eustace Cranch
August 25, 2016 2:13 pm

There are multiple potential explanations for the Permian extinction. The most obvious fact to consider is that the late Permian most closely resembles the “present” – in geological terms the Pleistocene and maybe Pliocene – of any period in the Phanerozoic (look up Geocarb III if you doubt this). It had an atmospheric carbon dioxide level very, very close the present, and was similar in temperature. So, a parsimonious explanation of the Permian extinction is that biological carbon fixing had depleted carbon reservoirs beyond the capacity of natural reservoirs to replace it. That in turn would result in a ecological instability and possible collapse all by itself. That in turn would reduce demands on natural carbon sources and allow a partial recovery planetary. By the end of the Triassic atmospheric carbon levels had reached about 50% the amount of the beginning Phanerozoic (about 10XRCO2 vs ca. 26XRCO2, where the present is 1XRCO2).
Geocarb III defines RCO2 as:
“RCO2 = the ratio of mass of CO2 at time t to that at present …”
It is worth considering that the extremely low levels of atmospheric CO2 during the LGM are very close to a point where primary production becomes problematic. Thus the dust levels of the Pleistocene, which are generally blamed on glacial loess, might be the result of desertification and savanna growth. The CO2 fertization effect on deserts that has been mapped by satellite imagery in the last few decades shows how well marginal environments respond to increased CO2. The emergence of Homo in the early Pleistocene is often associated with a loss of forest and increased savanna in Africa. Another factor to consider is the rise of the grasses. They emerge in the latter half of the Mesozoic. They do not however really take off as important ecological species until after the Cretaceous ends. They tolerate marginal weather conditions better than broad-leaved plants and conifers.
Turning back to the Permian/Triassic boundary, the formation of the Siberian traps ma have served to push an unstable global ecology into collapse, more because of the production of H2SO4 than because of CO2 or “global warming.” In fact, the CO2 output of the Siberian Traps could very well have lead to the Triassic ecological recovery. There is one geological fact that every climate scientis dabbling in geology seems to ignore: there has never been any period remotely resembling a stable atmospheric CO2 level. The closest are the present and the late Permian.

Reply to  Gabro
August 24, 2016 11:06 am

At least eight different scenarios have been plausibly posited, with some evidence. Even some explanations that do rely on global warming don’t blame CO2 alone, but methane, either from clathrates or microbes.
An hypothesis from 2014 implicates global warming from GHGs, but not CO2. Rather, the authors suggest that methanogenic microbes were to blame:
The scenario reported in this post relies instead chiefly on volcanism from the Siberian Traps, made worse by burning coal deposits.
Personally, I’m partial to the hydrogen sulfide hypothesis, as outlined in this link from 2005, elaborated more recently by Japanese researchers.….33..397K
But, as I said, about half a dozen other hypotheses have been proposed. It would have been easy for you to find them.

John M. Ware
Reply to  Gabro
August 24, 2016 11:16 am

I saw a TV documentary a few days ago about a huge crater possibly discovered beneath a deep ice layer on Antarctica. The crater came–if it exists, as evidence seems to show–from the impact of a decent-sized asteroid which blew up, creating a hole several times the size of the one near (?) the Yucatan Peninsula. Other effects included dust for a long time, and a reciprocal blast in Siberia (shock wave going all the way around the earth and meeting up with itself on the other side) with many effects of its own. I wish I could be more specific, but I was fixing supper at the time and could pay attention only intermittently. I did catch, however, the implication that this combination of events led to a large and widespread extinction.

Reply to  Gabro
August 24, 2016 11:21 am

The Wilkes Land Crater and other impact hypotheses have gained less support recently. This article from 2006 however proposes the Antarctic impact conjecture:

Reply to  Gabro
August 24, 2016 12:35 pm

There was a recent paper that suggested that the earthquake from Chicxulub impact may have greatly boosted size and rate of the Deccan eruptions, even though it was not in an antipodal position:
It is known that earthquakes can trigger or reinforce eruptions and an “asteroid earthquake” is orders of magnitude greater than any conventional earthquake can ever be. And there is evidence from Australia and Antarctica that a major impact occurred somewhere in the southern hemisphere near the P/T boundary.

Reply to  Gabro
August 24, 2016 2:33 pm

If such an impact occurred, odds are that it would have happened in the deep ocean, and seafloor is almost all younger than 200 million years, so we shouldn’t really expect to find the crater, if there ever were one.

Reply to  Gabro
August 24, 2016 5:46 pm

As cold is more deadly than hot, it is more likely that the low solubility of nutrients caused by the excessively cold oceans, as a result of a long period of volcanic eruptions—recognizing the decreased insolation from all of that extended atmospheric dust and such—was the factor that starved the recovery of life on Earth.
Why do they always ignore so many critical but obvious factors that need to be considered when claiming a particular result. Oh, wait, they have to cull out all factors that do not fit their narrative. It’s an agenda. Okay, then.

Reply to  Gabro
August 25, 2016 2:51 am

The traps also produced SO2 in large amounts together with CO2, H2S, HCl and HF.

Clyde Spencer
Reply to  Gabro
August 24, 2016 12:43 pm

How come you don’t spell your name with two “B”s? Do you use a German spelling?

Reply to  Clyde Spencer
August 24, 2016 1:49 pm

Clyde – after the River??
Ga Bro – Georgia Brother. That, I guess, is an American spelling.
Gamro – G. AmRo could be Guatemalan/Dutch [Amsterdam/Rotterdam] spelling, but – conceivably – is not. Even were it used.
Gam Ro – GAM [Collective noun for whales] RO – Rorquals.
Enough for the evening, I think.
Auto – autochthony as it is spelt.

Reply to  Clyde Spencer
August 24, 2016 2:27 pm

The plutonic rock is spelt the same in German as in English, ie Gabbro. But that’s not the source of my name. Schist is of course a geologic term.

Reply to  Gabro
August 24, 2016 5:07 pm

But, but I thought that volcanic eruptions dropped the temperature……

Reply to  Gabro
August 25, 2016 1:51 pm

The claim that the temperature rise was the cause is not explained by the paper either. It is instructive to know we are talking about CO2 at 3000ppm or nearly 8 times today’s levels and temperatures 14 degrees C higher than today not 0.3C. There was also massive amounts of methane and other gases. Over the next several 100 million years temperatures stayed 5 or more C above current levels and this is when almost all life we know today evolved.
It is important to note that although temperatures rose incredibly rapidly according to the geologic record indicating something catastrophic like a giant meteor strike or some gross instability in the earths crust releasing vast amounts of material we don’t know if it was the heat or the chemicals released, the immediate cause of death could have been extreme heat far above 14C due to whatever caused the event, or materials in the environment. There is no causal link between the death and temperature. It is an assumption.
This assumption is weakened in terms of its relevance because if temperatures 4C or higher above current levels were toxic to human or plant life then it is hard to see how life managed to emerge and prosper after that period given the extremely toxic environment posulated by 4C above todays temperature. The evolution and prospering of life during this period would indicate the opposite, that in fact temperatures up to 10C higher are probably not toxic to most currently evolved biota on the earth that has emerged since 200 million years ago.

Tom Halla
August 24, 2016 10:53 am

Seems like another case of proxies all the way down.:-)

August 24, 2016 11:03 am

Yeah, it was totally the heat…never mind the russia sized sheet of lava miles deep erupting for thousands of years and an ocean that had gone so acidic that a large percentage of what should have been fossilized shells vanished. No…it was totally the heat and there was nothing else important going on.

Reply to  poitsplace
August 24, 2016 11:19 am

And anoxic. Ocean anoxia is a major contender for the main culprit.

Reply to  poitsplace
August 24, 2016 11:25 am

Absolutely! Now, write a paper, put “PhD” behind your name, and publish it. Some prestigious journal will publish, no questions asked, and you, too, can be famous as the globalwarmist world sings your praises for upholding the honor of true science.

george e. smith
Reply to  Richard
August 24, 2016 11:59 am

You would be the world’s leading authority on the Phosphorous-Tracium extinction.
And also the only person on the planet with any interest in that. So start looking for a post doc fellowship if you can’t find a real job.

August 24, 2016 11:04 am

When they use the term ‘global warming’ for this natural disaster in the distant past they must know that they are mixing it with a politically loaded term in its modern meaning. It draws a parallel between the two and implies they are the same sort of phenomenon and danger level. Then at the end they specifically draw another parallel between the Siberian Traps and “human activities”, implying directly that modern global warming caused by CO2 ill lead to the same sort of extinction as in the past. There is no logic in this, since the two are completely different in cause and effects. There is no scientific reason to make this analogy. It can only be to garner attention by fishing for an emotional reaction.

Reply to  TDBraun
August 24, 2016 11:17 am

Of course this is just spinning to try to bolster the crooked consensus.
The fact is that for most of the Permian, earth was still in the ice age which began in the preceding Carboniferous Period. This naturally produced low CO2 levels, around present day or lower, although perhaps not as low as during the Pleistocene glaciations. CO2 did apparently increase in the Late Permian, so that the average concentration for the whole Period is estimated to have been around 900 ppm.
But CO2 was much higher both before and after the Permian, without an associated mass extinction event.comment image
The estimated average for the Carboniferous is around 800 ppm, with higher early on, at the time the ice age began, then lower later due to the cold conditions.
The estimate for the following Triassic Period however, during which time recovery from the P-T MEE occurred, was 1750 ppm, ie double the average for the Carboniferous and Permian. In the following Jurassic, it was 1950 ppm and 1700 ppm during the Cretaceous Period, which was generally warmer than the Jurassic, indeed downright hot.

Reply to  Gabro
August 24, 2016 11:18 am

comment image

Jim Yushchyshyn
Reply to  Gabro
August 24, 2016 5:16 pm

“Crooked consensus”
If you can’t respond to science with science, resort to personal attacks.

Reply to  Gabro
August 24, 2016 7:19 pm

The so-called consensus is Cooked, not crooked…

Reply to  TDBraun
August 24, 2016 5:22 pm

But it is objectively crooked.
Read the emails. Although everyone watching closely already knew that the perps were crooks and shameless liars, all for “the cause”.

August 24, 2016 11:06 am

“Today some scientists argue that we are facing a new mass extinction period, mostly caused by human activities.”
Gotta love the line added by the grants administrator.

Vlad the Impaler
August 24, 2016 11:26 am

A quick perusal of Bill Illis’ graphs from a few weeks ago shows that
1) proxy delta-O-18 temperatures were in decline through the late Permian, and into the early Triassic;
2) most of the diabase was erupted during the two-to-three million years AFTER the terminal extinction event had occurred; only a small part of it took place in the late Permian;
3) volcanic aerosols typically produce cooling by partially blocking sunlight;
4) the extinction event was several million years long, culminating in a “sudden” (geologically speaking) terminal event (Araganty? Wilkesland?) at the very end of the Permian (and “sudden” geologically is [up to] several tens of thousands of years).
Yet another example that to get published and funded, you have to make it “global warming”, not global cooling (which it was).

Reply to  Vlad the Impaler
August 24, 2016 1:49 pm

4) the extinction event was several million years long, culminating in a “sudden (geologically speaking) terminal event (Araganty? Wilkesland?)

The trilobites had been declining for many millions of years (since the Devonian) until their final extinction at the P-T boundary.
I agree, it doesn’t seem to be a simple story.

August 24, 2016 11:29 am

Nutrient poor waters in one place now in Canada does not mean nutrient poor elsewhere. Ocean current upwellings are not uniformly distributed. The ‘explanation’ lacks global credibility.
There is evidence even in the Red Sea for significant ocean acidification from eruptive SO2 and CO2 from burning what are now Siberian coal seams (even ‘fly ash’ and ‘soot’ in Chinese lakebed sediments). It would take millions of years of erosion to rebuffer the ocean chemistry. So that is a competing hypothesis. Another is that with such a great loss in biodiversity in an adverse environment, evolution simply took a few million years to rediversify complex ecosystems.

Reply to  ristvan
August 24, 2016 2:31 pm

IMO that is also why it took well into the Triassic for diversity to recover, although the time actually required is a matter of some debate.

Reply to  Gabro
August 26, 2016 6:56 pm

The most likely “cause” of the Permian extinction is an excessively efficient ecology confronted with an inadequate natural carbon supply. It becomes inherently unstable. The system through one or more triggers finally goes TU. Not all life vanishes and as natural carbon supplies replenish the level of available carbon, things begin recovering. Depending precisely on when the Siberian traps are forming, they could either have helped trigger the final Permian collapse, or through volcanic CO2 releases and burning coal, helped with the ecological recovery following the extinction, or possibly both. There almost certainly is no neat single “cause.” It is notable that the Mesozoic recovery never sees available carbon levels reach more than about half the Paleozoic levels and we are now back to late Permian levels, which, I submit, really is something to worry about.

Thomas Homer
August 24, 2016 11:39 am

From the article …
“And without algae, which are the base of the food chain, the life in the ocean did not thrive.”

– web definition of algae:
Algae – is an informal term for a large, diverse group of photosynthetic organisms
As we know, photosynthetic means that algae consumes CO2. So, rather than algae being the base of the food chain, it should read:
CO2 is the base of the food chain

Reply to  Thomas Homer
August 24, 2016 11:42 am

It’s unclear whether the authors mean actual algae or cyanobacteria, often incorrectly called “blue green algae”.

Thomas Homer
Reply to  Gabro
August 24, 2016 12:05 pm

[ Cyanobacteria /saɪˌænoʊbækˈtɪəriə/, also known as Cyanophyta, is a phylum of bacteria that obtain their energy through photosynthesis ]
CO2 is the base of the food chain … as it is today, for all Carbon based life forms.

Bill Illis
August 24, 2016 11:40 am

Let’s say a volcano opened up in the middle of the US and then poured 1/2 km of lava across the entire continental US. Thats how big the Siberian Traps volcanoes were.
Besides everything in the US becoming extinct, the rest of the Earth suffers considerably with all possibilities including the atmosphere becoming poisonous, to oxygen levels falling below life sustaining levels, to no sunlight for the million years it lasted to basically anything.
The do18 isotopes show that the Earth actually cooled off considerably during the extinction event and was much warmer 15 million years before the event (when no extinctions occurred)comment image

Reply to  Bill Illis
August 24, 2016 12:04 pm

The proposed reason the Siberian Traps extinction were so much more calamitous for life was that, unlike the Peruvian traps which erupted through a desert floor crust, the Siberian Traps erupted through massive coal beds laid down 100 my earlier during the Carboniferous.

Reply to  joelobryan
August 24, 2016 12:23 pm

You often see that claim, but no. There is barely any coal in the area, but there are deep organics-rich shale deposits.

Reply to  joelobryan
August 24, 2016 5:20 pm

There was coal, but it all burned up!
So there.
(Just kidding.)

Bill Illis
Reply to  joelobryan
August 24, 2016 6:33 pm

Actually, there were (are still are nearby) large coal-fields in the Siberian Traps region. But does several metres/100 metres of coal compare to the 4,000 metres of lava erupted from deep within the Earth. The outflows were 4 kms high on average in the region.
The coal fields are just a misdirection from the CO2 crowd. Any rock heated to lava-type temperatures will outgas any number of unusual gases that goes into the atmosphere.
I think any series of volcanoes this large, or the main event which happened right exactly at the timeline of the Extinction Event, indicates that …
… the atmosphere was just not breathable (for complex Oxygen-breathing) organisms. Try breathing in some fluorine gas for an hour or so and see what happens. Now do that to every animal and sea creature on the planet for several days at a time about 10 times per year lasting over 100,000 years or so during the main event and see what happens. Let’s say Oxygen levels were burned so fast up so that the atmospheric level fell from a quite high 26% at the time (ie fires were unstoppable at the time without days and days of rain) to just 13% because of all the burning caused by these absolutely massive lava outflows.
ie. The organisms are all gone. Maybe it was not that bad but it probably was.

Bill Illis
Reply to  joelobryan
August 24, 2016 7:18 pm

What is also interesting that of the land animals at the time, let’s say there were four basic types. The mammal-like reptiles (which were completely dominant at the time and contained some species which were very, very mammal-like), reptiles, others, and a single reptile that had directly forward leaning legs versus the other reptiles and mammal-like reptiles which had legs which leaned outward like alligators today.
The reptile with the directly forward leaning legs survived (and a few reptiles and a few amphibians etc.) and only one of the mammal-like reptiles.
The reptile with the directly forward and backward leaning legs led to the dinosaurs (which dominated the world for the next 185 million years, the more efficient locomotion was very advantageous) and the sole reptile-like mammal which survived, lead to the mammals and us 185 to 240 million years later.
That is how tight this extinction was.

Reply to  joelobryan
August 25, 2016 3:39 pm

Is that Lystrosaurus you are referring to (burrow-dwelling mammal ancestor)?

Reply to  Bill Illis
August 24, 2016 2:22 pm

Great explanation, map and palaeo data.
But “ice cores” in the temp / CO2 figure cant be right – what ice cores go back 275 million years?

Bill Illis
Reply to  ptolemy2
August 24, 2016 5:56 pm

The dO18 isotopes come from many, many different cores (ice cores going back to 800K years ago, ocean crust cores going back to about 400M years ago and dated continental/inland sea cores going back to 3.5B years ago) Altogether, there are about 24,000 individual estimates so this is a very big database.
This is just a zoom-in of the complete record so one can see what happens right at the Permian Extinction Event but one can do a zoom-in for any period or cover the whole 3.5 billion years of the record (note the CO2 numbers don’t really go past 750 Mya except through the some experimental techniques.)

Reply to  ptolemy2
August 25, 2016 3:42 pm

It’s fantastic data. It refutes by itself the idea of CO2 being a strong or dominant warming agent. It’s an anti-PETM. More should be made of it.

August 24, 2016 11:45 am

Just not enough stratigraphic information to make such a claim. The Permian began during the middle/end of a major glaciation, new species (we’re talking primarily marine species in Permian event) responded to that change (including to lower sea levels). As the Permian continued, Pangaea became more elevated and the intercontinental seaway’s that dominated the previous 250 my disappeared. Major marine species reorganization (and specialization) took place, while globally the climate became drier over most of Pangaea, which likely means greater dust production, and as we see today downwind of major deserts, a potential increase in Fe and Al production seeding the oceans surrounding Pangaea. At the Permian event, multiple activities changed, less shallow marine production, wetter climate, sea level fall, Siberian volcanic activity, which are all potential tweaks to species in major turnover at the extinction boundary….

August 24, 2016 11:46 am

Seems likes lots of hand-waving going on here.
But to be sure, the (Permian-Triassic Boundary) PTB mass extinction event from the Siberian traps released about vastly more carbon dioxide more than even the worst case, high-end scenarios of anthropogenic carbon releases. The more likely modern anthropogenic scenarios put future pCO2 in the 650 ppm to 1200 ppm range if all extractable fossil fuels are burned to reservoir exhaustion. The pre-PTB pCO2 is estimated to have been around 3X Present Atmospheric Level (PAL), around 1000-1200 ppm. During the PTB, two extinction-associated pulses of carbon release are observed in carbon and boron proxies. Extinction Pulse 1 (EP1) changed the exisitng pCO2 very little, but EP2 was much different. Educating oneself on the existing literature finds this Science article from April 2015:

Ocean acidification and the Permo-Triassic mass extinction.
authors: M. O. Clarkson, S. A. Kasemann, R. A. Wood, T. M. Lenton, S. J. Daines, S. Richoz, F. Ohnemueller, A. Meixner, S. W. Poulton, E. T. Tipper
Science 10 Apr 2015:
Vol. 348, Issue 6231, pp. 229-232
DOI: 10.1126/science.aaa0193
“This is undoubtedly a massive injection of 24,000 PgC at a rapid rate of 2.4 PgC/year, but it is physically plausible given existing estimates of the volume of carbonate host sediments subject to contact metamorphism and postulated mechanisms of carbon release (supplementary text). This second rapid carbon release produces a sharp rise in PCO2 to ~20 PAL and warming of ~15°C, which is consistent with the observation of peak temperatures after EP1 (22).”
………….(in their conclusion)
“The PTB was a time of extreme environmental change, and our combined data and modeling approach falsifies several of the mechanisms currently proposed. Although the coincident stresses of anoxia, increasing temperature, and ecosystem restructuring were important during this interval, the δ11B record strongly suggests that widespread ocean acidification was not a factor in the first phase of the mass extinction but did drive the second pulse. The carbon release required to drive the observed acidification event must have occurred at a rate comparable with the current anthropogenic perturbation but exceeds it in expected magnitude. Specifically, the required model perturbation of 24,000 PgC exceeds the ~5000 PgC of conventional fossil fuels and is at the upper end of the range of estimates of unconventional fossil fuels (such as methane hydrates). ”

Realize that 20 PAL is around 20x400ppm= 8000 ppm. So we can turn off the alarms for anthropogenic carbon alarmism.

August 24, 2016 11:48 am

Another explanation is built around the discovery of a massive impact crater buried under the ice in Antarctica that has geologically been dated to about the same time period. This crater is the largest that has been discovered on Earth.

Reply to  fthoma
August 24, 2016 6:31 pm

Yes and Right next to the pyramids under 2 miles of ice. Amazing!

Steve in SC
August 24, 2016 11:55 am

You gotta love it. The PT extinction explained in a paper by PT Barnum.

David Hutchings
August 24, 2016 12:00 pm

You could look at it this way.
“The mass extinction was likely triggered by a explosive event of volcanic eruptions in what is now Siberia. These eruptions lasted for a million years and emitted enormous amounts of volatiles, such as carbon dioxide and methane, which made our planet unbearably hot.” says Jochen Knies, researcher at CAGE.
Yet life on earth survived. 30% of life on land and 4% in the oceans. However, present day global climate change is dooming us all!

Bill Illis
Reply to  David Hutchings
August 24, 2016 12:57 pm

Look at the map of Pangea and see where the Paleo-Tethys Ocean is. This ocean was relatively enclosed by land and situated at the equator and situated where the Pacific Warm Pool region would have been 251 million years ago. And then the Paleo Pacific Ocean was 50% wider than the current Pacific ocean is.
Ie. the Trade Winds were constantly moving hot water in from the equator from a very wide ocean (on a planet that was up to 10.0C warmer than today already).
Ie, Periodic ENSO-like events probably pushed the Paleo-Tethys Ocean temperature into the 42C to 45C temperature range. Being relatively enclosed it might have even gotten warmer.
This is “too hot” for complex lifeforms and it probably only contained bacteria for extended periods of time.
Can you say anoxic dead ocean and all sea-life dying. Just a function of a warmer world with a certain geographic alignment.

Reply to  Bill Illis
August 24, 2016 1:36 pm

There is good evidence that some marine organisms can tolerate temperatures in that range:

Reply to  Bill Illis
August 24, 2016 10:32 pm

Ocean anoxic events are a life’s work in their own wright. There are many, many more than during the PTr extinction. What strikes me about the PTr is how low sea level was.comment image
The apparent difference between the PTr and the Cretaceous “hothouse” is that sea level was much higher in the K. (Not looking so good for us now if it gets hot unless we coax sea level up a bit)
So what is sea level? It is some unknown combination of more or less water and whether the isostatic lift is under the ocean or under the continents. During the Cretaceous the Large Igneous Provinces were largely sub oceanic, displacing water onto land. Lots of shallow water above the carbonate compensation depth. Inland seas cover much of North America.
Reverse the scenario and lift Siberia. Sea level drops. The volcanic gasses, rather than being bubbled through the ocean, burn through the much distilled continental crust laden with Boron, Chromium, Cobalt, et al. and inject directly to the atmosphere…

Reply to  Bill Illis
August 25, 2016 10:14 am

Here’s a site that shows how the Dead Sea responds to high summer T:

August 24, 2016 12:03 pm

Hoo, what a stunning series of falsehoods.
From one news article to another, then to another, on and on; each with fantastic claims and echoes of doom.
One keeps link through to an article’s source; eventually one ends up where the rumor mill starts.

Early Triassic productivity crises delayed recovery from world’s worst mass extinction” Geology, September 2016

How “delayed recovery” transmutes into “Extreme global warming caused a severe mass extinction of life” is because alarmist folks wrote their own bias into the titles.
The ‘study’ still translates into a small bit of geological research buffed into a glorious ‘end of life’ 3D Godlike fantasy upon which all of Earth depends.

August 24, 2016 12:11 pm

As always in these cases the actual paper ”Early Triassic productivity crises delayed recovery from world’s worst mass extinction”
is a lot less dramatic than the press release.
Essentially it concerns changes in nitrogen isotope ratios over the P/T boundary and Early Triassic from three sites in Arctic Canada. They interpret these as indicating that upwelling ceased for a prolonged period. If this was true I would expect the other (and usually more critical) nutrient involved in upwelling, i e phosphorus to also decrease. However it does not, if anything the amount of phosphorus increases in the Early Triassic above the P/T boundary which seems extremely strange if there was no upwelling. Also when marine conditions return to normal in the middle Anisian nitrogen isotope fractionation actually goes down a bit, not back up. It is clear that there were dramatic changes in ocean nitrogen chemistry at the P/T boundary, but it seems quite unclear what they were and what caused them.
To return to the rather more lurid press release: volcanoes of course do not erupt methane. The Siberian Traps did erupt through an organics-rich sedimentary basin that may have enhanced CO2 emissions. However the idea that methane, which even breaks down in just a few years in the atmosphere, would have survived passage through a volcano is absurd.

Tim Ball
August 24, 2016 12:36 pm

I am always troubled by claims using imprecise dating. According to Burgess et al.,
“The extinction occurred between 251.941 ± 0.037 and 251.880 ± 0.031 Ma, a duration of 60 ± 48 ka.”
This may be precise in geologic terms but how applicable is that to climate. If Sir Charles Lyell is correct and the present is the key to the past, then how much climate change occurred in the same period counting back from today? It is critical because you must have the right sequence of events to determine cause and effect.

Clyde Spencer
Reply to  Tim Ball
August 24, 2016 12:54 pm

James Hutton, not Lyell.

Tim Ball
Reply to  Clyde Spencer
August 24, 2016 1:06 pm

But it was put into main stream thinking by Lyell, whose book “Principles of Geology” accompanied and greatly influenced Darwin’s thinking while on his Beagle voyages.

John Robertson
August 24, 2016 12:37 pm

The last sentence is the good one “Today some scientists argue that we are facing a new mass extinction period, mostly caused by human activities.” I think that life on earth is more at risk from nuclear weapons or pollution side effects than any possible human caused climate changes – unless some silly buggers try to ‘fix’ the ‘climate crisis’ by experimenting with terraforming the earth. Frigging scary that one!

August 24, 2016 12:48 pm

I will look at my crystal ball… I say that a series of strikes from a breaking up comet caused … whatever you want. At least my theory has a witnessed event in recent history on Jupiter to back it up as possible. Since current science is no longer theorize, then attempt to prove… I could be just as right as the author of this article. Heck my supposition could have even caused his volcano. If I could spin in Co2 bad… I could probably even get funding:) If I can somehow make it man’s fault.. damn.. I’d be rich. Its sad, Science has fallen back into the dark ages. If the kings of funding do not like your science you are labeled a heretic and with the current mood of the climate science cult.. I suspect the burned at the stake part is not far behind.

August 24, 2016 1:05 pm

Sorry folks, parks closed. The moose out front should have told you.

Reply to  Scott Frasier
August 24, 2016 1:24 pm

I love that movie.

August 24, 2016 1:05 pm

oh and the whole Pangea theory seems to be in question as well. So if you base your unproven science on other unproven science .. do you get a special prize?

Reply to  pkatt
August 24, 2016 1:15 pm

a grant from the Gov’t. PseudoScience is the craze these days.

August 24, 2016 1:06 pm

Considering the P-Tr extinction was especially devastating to marine life, I would think that the main culprit among the emissions from the formation of the Siberian Traps would have been oxides of sulfur, a major component of many volcanic emissions and a powerful acid, which could have lowered the pH of the oceans significantly.
Methane is NOT a significant component of volcanic gases, but rather originates primarily in sedimentary rocks from anoxic decomposition of organic compounds (fossil plants and animals). The speculation of the late Tommy Gold concerning ‘primordial gases’ being trapped in the molten mantle rock was never borne out by empirical investigations.
Most of the petrochemical carbon dioxide is also produced in sedimentary rock by the action of acidic water (rainwater) on carbonate minerals.
Sulfur is released from magma through the thermal decomposition and oxidation of sulfide minerals. Even today volcanoes are major sources mined sulfur (Google ‘sulfur mines’). Some volcanoes are *continually* emitting sulfur oxides from the ‘perpetual’ flames of burning sulfur.

Lil Fella from OZ
August 24, 2016 1:42 pm

Ask them to prove it!!???

Clif westin
August 24, 2016 1:54 pm

Great documentary on this. They go through a number of potential causes and end up with the volcanos splitting Siberia apart. Over 1,000 mile long volcanos. Spoiler alert, it took 75,000 years of this to warm the earth enough to cause the extinctions…,

Reply to  Clif westin
August 24, 2016 6:02 pm

Wouldn’t a volcano 100,000 miles in length not warm the atmosphere? That warming wouldn’t be due to CO2, it would be due to the lava. A 100,000 mile long volcano, erupting for million of years would warm the atmosphere, but that would have nothing to do with CO2, just like the year without a summer wasn’t due to CO2.

August 24, 2016 2:17 pm

I didn’t know coal burning power plants and SUVs existed 252 million years ago.

NW sage
Reply to  CO2isLife
August 24, 2016 4:24 pm

Yes, they were both very common until Consumer Reports called them out as unsafe at any speed. It took them literally forever to come back. [does tongue-in-cheek count as ‘sarc’?]

Reply to  CO2isLife
August 25, 2016 1:26 am

Surely you have watched Fred Flinstone?

Kevin Kilty
August 24, 2016 2:31 pm

Yes, this may have a lot to say about how climate change may progress on Earth if our atmosphere becomes filled with not only CO2, but also the other volatiles associated with volcanic eruptions, such as HCl, SO2, and so forth. Tim Ball has the right response to all such studies. A necessary (but not sufficient) condition to prove cause and effect is a tight constraint on the timing and sequence of events that is never available from isotope chronology.

August 24, 2016 2:32 pm

Probably brontosaurus flatulence. And other herbivores. Lol. So don’t be blamin no T-Rex.

Reply to  Logos_wrench
August 24, 2016 2:38 pm

As you may know, the P-T event occurred long before there were any dinosaurs, and indeed cleared the earth for them to evolve from the previously minor faunal element of archosaurs or proto-archosaurs.
The dominant land animals of the Permian were synapsids, mammal-relatives like Dimetrodon. Dinosaurs and other archosaurs (such as pterosaurs and crocodilians) are diapsids, along with the lepidosaurs (snakes, lizards and tuataras). Turtles are also probably phylogenetically diapsids, but their skulls are presently “anapsid”, ie lacking holes in their heads in back of their eye sockets. Synapsids have one such opening and diapsids two.

August 24, 2016 3:27 pm

A volcano of that size most likely have caused extreme cooling, not heat. Today the estimate claim volcanoes don’t produce significant CO2. Why the change?

August 24, 2016 3:49 pm

Many, many moons ago, there was a TV ad claiming that ‘a day without orange juice is like a day without sunshine.’
Nowadays it seems that a day without some “scholarly” paper or other (and particularly its carefully crafted Press Release for the benefit of dutiful MSM auto-recyclers) harping on trumped up “dangers” of global warming, climate change – or whatever the UN’s tweeted danger-flavour of the day might be – is rapidly becoming, well, like a day without news!
And on a somewhat related, albeit verging on O/T but IMHO amusing, aside …
I noticed that the ads I was served with this post were (top) BC Lotto Corp flogging an invite for me to play online and (bottom) flogging Naomi Klein’s latest polemic, This Changes Everything.
Amazing, eh?!

Jim Yushchyshyn
August 24, 2016 4:15 pm

How hot do they think that Earth could have been at that time?
Probably hotter than Earth would be if we continued to burn fossil fuels for a thousand years and if climate sensitivity is 4.5C.
I do believe that we should combat global warming, but, I very much doubt that its effects will be as severe as whatever caused the Permian extinction.

Reply to  Jim Yushchyshyn
August 26, 2016 7:08 pm

The earth was about the SAME temperature as it is NOW. It was considerably warmer before AND afterward. The extinction did not happen because of “climate” change.

Reply to  Duster
August 26, 2016 7:08 pm

Although, it IS possible climate changed because of the extinction.

Mike Maguire
August 24, 2016 4:43 pm

Something happened on this planet 252,000,000 years ago. It’s always interesting and often enlightening to read about speculative theories from scientists that explain the when, where and how various combinations of factors combined in our past.
Of course we frequently have other, just as qualified scientists with competing speculative theories that seem to make just as much sense. It would be impossible (at least for me) to know which speculative theory or what parts of other theories to put together with confidence to fully explain what actually happened.
The ending “opinion” tells us a great deal about the authors mindset……making a connection between the extreme conditions in his speculative theory about earth 252 million years ago and a suggestion of an earth today suffering from extreme conditions, this time caused by humans.
“Today some scientists argue that we are facing a new mass extinction period, mostly caused by human activities.”
We will never know if the extraordinarily extreme conditions in the very distant past, 252 million years ago happened the way this study suggests. I am pretty sure though, that a similar mass extinction on this planet will not occur from human activities.
For sure it won’t be caused by a global temperature increase of a couple of degrees and the increase in the beneficial CO2, which is unlikely to get to 600 ppm, has so far, been welcomed by most life on this greening planet.
I’ll bet we can program models to show mass extinctions!

August 24, 2016 5:05 pm

Yet another [though not particularly new] entry into the P-T extinction discussion
Succinctly covered in Wikipedia…–Triassic_extinction_event
It’s a bit like saying I’ve come up for an idea for a new breakfast cereal

August 24, 2016 5:42 pm

Wise people apply the knowledge of the past to present problems. Charlatans apply the myths of the present to problems of the past..

August 24, 2016 5:49 pm

“Today some scientists argue that we are facing a new mass extinction period, mostly caused by human activities.”
Well. As long as these “scientists” are the first to go,the rest of us will be able to enjoy more food,less violent storms,and money grubbing from eco-AGW cultists. Hey,I can wish!

August 24, 2016 6:40 pm

now THAT’s gonna set the bronze age back a bit.

Walter Sobchak
August 24, 2016 7:12 pm

Eugene WR Gallun
August 24, 2016 7:28 pm

Mass volcanic eruptions in Siberia that lasted a million years? That creates quite a mind image.
But don’t volcanoes erupt because of a build up of “pressure” inside the earth? And the reality is that most eruptions don’t last long, ending when that pressure is relieved. (Ok, some simmer on and on but not many.) So once relieved, this pressure inside the earth immediately built up again and new volcanoes erupted or old ones erupted again?
Ok, so where did all this pressure inside the earth come from that caused mass volcanic eruptions in Siberia that lasted a million years? What was causing the earth to puke its liquid guts out — coupled with a bad case of gas that fouled the atmosphere — both lasting a million years?
Has anyone ever suggested an answer to this? Where was all that internal pressure coming from?
Eugene WR Gallun

Reply to  Eugene WR Gallun
August 25, 2016 2:01 am

Mid-Ocean ridges are essentially volcanoes, albeit rather long ones.
The oldest oceanic crust in the Indian Ocean is about 140 million years old which suggests that volcanism along the Mid-Indian ridge has been taking place for 140 million years. Along the Pacific and Atlantic mid-ocean ridges volcanism has been occurring for around 200 million years.

Eugene WR Gallun
Reply to  GregK
August 25, 2016 4:47 am

Greg K
Well, that is information but I don’t see how that explains the eruptions in Siberia which supposedly caused a great mass extinction.
Since the Mid-Indian Ridge has been active for 140 million years and the Pacific and Atlantic Mid-Ocean Ridge has been active for 200 million years and neither has caused any mass extinctions i would suspect that plate movement was not responsible for Siberia. Do you think otherwise?
Eugene WR Gallun

Reply to  Eugene WR Gallun
August 25, 2016 4:32 am

In the formation of Pangea, the area in Russia where the Siberian Traps occurred had been drifting north for about 100 million years. The area probably overrode some other continental crust, an ancient smaller craton that is now gone of course so we don’t know about it.
When continental crust is driven down into the mantle and subducted under other continetal crust,it eventually melts out because it has slightly different chemistry. It becomes lighter than the rest of the mantle and less viscous and it comes back out in volcanoes.
A super-continent is also going to put tremendous pressure on the mantle below and they eventually split apart as the mantle pressure builds up. 50 million years after the Siberian Traps, the Central Atlantic Magamtic Province started the split apart of Pangea as North America split from Africa and South America and began the process which led to the Atlantic Ocean. These volcanoes were also massive and probably led to the Jurassic Extinction. Yes
, the Atlantic is only 200 million years old at maximum and some parts were just created yesterday.
Pressure from a super-continent above, subducted old continental crust. Magmatic Province release.

Reply to  Bill Illis
August 26, 2016 7:55 am

Great reply as always.
In reconstructions of continental drift over the Phanerozoic I get the impression that the total continental land area has steadily increased, from 600 mya up to now. Is this correct – or is the data accurate enough to say that?

Reply to  Bill Illis
August 26, 2016 7:25 pm

Bill, continental crust tends to more acidic (i.e. granitic). It contains less iron and magnesium and more aluminum and silica. Magma with a granitic chemistry (low on the Bowen’s Reaction Series) tends to be very viscous, not less. Volcanoes over such melts tend to be explosive and discharge rhyolites and lava of similar silicic chemistry. The volcanic arcs along the continental sides of subduction zones are typified by stratovolcanoes. Shield volcanoes, e.g. Hawaii or the plateau basalts of the US northwest, the Deccan Traps, and (perhaps) the Siberian traps, are more often associated with mantle plumes (which are hypothetical but still one of the only efficient ways of explaining phenomena like the Hawiian/Emperor seamount chain). In gneral, the lower the specific gravity a lava has, the lower its melting point and the higher its viscosity when melted. Whether the Siberian Traps were associated with a mantle plume is debated, but there is evidence that there may be a plume.

Reply to  Eugene WR Gallun
August 25, 2016 10:38 am

It’s the pressure differential that matters, and you get a chimney effect: the higher the magma plume the more the magma floats–the more negative pressure it gains. Outhouse manufacturers now use chimney pipes that take advantage of the warm gas in the poop tank. This ventilates the tank and the outhouse at the same time, and they don’t stink any more. It’s a marvelous scientific advance, and probably not instigated by NASA. –AGF

August 24, 2016 8:57 pm

But it’s Anthroprogenic Climate Change now, that’s not Global Warming.
I doubt it was caused by the CO2 anyway. 100% of temp increases in the last 100 years has been Albedo change.

August 24, 2016 11:47 pm

And what caused the excessive Siberian volcanism?

Reply to  thingodonta
August 25, 2016 8:06 am

That is my problem with the entire thing.
What is the cause? A few people have tried to answer it but that all assumes the Earth was stable in its orbit, the sun’s output was the same or nominal to the cause..etc. Why are we only looking for evidence in ice cores and nor correlating that data with the astronomical record?
In other words what the heck happened to cross referencing?
What really happened? Dunno. But if you take all the hypothesis togethet, you’ve got one heck of a strike on Antarctica, the Tethys shallow sea, Siberian volcanoes, plate tectonics and added pressure from in the Earth itself. Ok, those are great clues…particularly the massive size of the volcanoes and the length of time they erupted. But it never answers or even posits the why. Are all of these related to something else? What was the sun doing at the time? Did the moon dip into its lower orbit causing tidal fluctuations in the mantle causing the pressure build up? Not unheard of, we have posited this is happening in our solar system now. So is it some kind of the same? How about that comet? Was it a comet or a 2nd moon in a deteriorating orbit that finally crash landed?
These are all rhetorical questions the scientists of this study needed to answer or at least consider before blaming CO2, methane and claiming nitrogen is the only nutrient in the ocean, and that volcanoes burst forth only CO2 and methane. What???!!!!
I give by this paper a C for effort but a lazy one at that.

Reply to  thingodonta
August 26, 2016 7:37 pm

The planet, if you view its geological history in fast forward, is really quite a violent place. There are several problems in geology that have been and remain difficult. One is the formation of shield volcanoes, which seem mostly to associated with “fixed” hotpots – mantle plumes – which the crust, both oceanic and continental move over with time. If you look at a map of the Pacific ocean floor for instance you can trace a line of undersea mountains, extinct volcanoes from Hawaii northwest to Midway Island. A little farther northwest and the chain turns almost due north meeting the junction of the Kurile Islands and the Kamchatka Peninsula. A similar trail of destruction travels from the Pacific coast eastward to Yellowstone and is known as “the Plateau.” Another suggestion is that major asteroid impacts one side of the planet may trigger major volcanism on the opposite face. But, all crust is in motion and the majority of it is not nearly old enough to record these events. Only relatively small areas within the continents retain truly ancient geology.

Ed Zuiderwijk
August 25, 2016 1:01 am

Given that CO2 is not a strong climate driver at the atmospheric level required for plantlife (i.e. over 250 ppm) and that Methane is even less so, the conclusions are based on false assumptions. There may have been a temperature event as described and it may have been due to volcanic activity but the mechanism had nothing to do with either CO2 or Methane.

Mark - helsinki
August 25, 2016 1:11 am

Yawn, more “all things being equal” science”
For example, and it’s a big assumption. These reconstructions always assume that the solar system was always stable. That’s the sun is always stable, that everything is always stable so blame methane and CO2?
When one considers how much spewed from the Siberian traps..
Furthermore, Siberia and surrounding areas would have looked like the usual depiction of Hell.
We are talking one massive area where serious heat among other things was being pumped into what was a different atmosphere than we have today, in content and size, the atmosphere was no doubt shallower than today, which makes all that heat being pumped out from the planet even more effective.
There was no need for CO2 to warm things, this huge event went on for how long?
It seems that things were already quite stressed out when the Siberian traps went off.
Imo it was changes to water chemistry that killed ocean life, more than heat, though heat probably had an effect, but these kids of eruptions turn water to acid, literally acid.
Sulfur, there must have been epic amounts of sulfur put into the atmosphere and unlike CO2, sulfur can and currently is acidifying waterways, but not oceans, sulfur the very thing the IPCC wants to use to save us from “global warming”!

Mark - helsinki
Reply to  Mark - helsinki
August 25, 2016 1:23 am

Wasn’t there similar going on in what is now Oman, the traps there.
There was huge continental geological changes around this period.
This is more “venus” analogue science, lets forget the geological history, lets forget the actual physical events and the posibilities, and just blame 2 gases which conveniently are the evil gases of the “Global warming doom”
NonScience nonsense

Peter Foster
August 25, 2016 2:03 am

The claims do not fit the timing of events. The ice age ended abruptly about 275 mya. At the same time a decline in oxygen started that took oxygen from around – to 35% of the atmosphere down to 15% at 252 mya. It is known that the oceans became anoxic towards the peak of extinctions and allowed sulphur bacteria producing H2S to dominate making the oceans or parts of them very toxic.
At that time gas exchange systems were very primitive and not all that efficient so that the drop in O2 would have been devastating.
Question – what caused oxygen to decline and why were plants not able to sustain O2 levels.
It should also be noted that 252 mya was the end of the extinctions not the start, they started some 15 million years before that, long before the Siberian traps volcanoes started.
The scenario that best fits the data is that the end of the ice age and removal of ice on Earth exposed rock such as pyrite in which iron as Fe 2+ was oxidised to Fe3+ removing oxygen from the air (combustion would not explain the reduction in oxygen as it would increase CO2 by the same amount, that clearly did not happen)
Plants could not replace the oxygen as CO2 was only 300 ppm restricting growth(far below the optimum of 1000+ ppm )
Consequently the combination of removal of oxygen and inability of plants to replace it lead to a decline in O2, as is happening now.
At 252 mya the extinctions ceased and biodiversity started to increase again as CO2 rose through 1600 ppm and continued to rise thereafter. Had CO2 been the culprit then biodiversity would not have increased post 252 mya (also note that the main Siberian Traps volcanoes were centred more on 248 mya not 252 mya.The increase in CO2 prior to 252 mya may well have been due to decomposition of dead organisms rather than volcanic.
The data suggests that the extinctions were caused by a drop in oxygen that occurred due to the lack of CO2. Only when CO2 increased beyond 1600 ppm did the extinctions cease.

Mark - Helsinki
Reply to  Peter Foster
August 25, 2016 9:06 am

CO2 decrease most likely killed the plants off, and most oxygen comes from the ocean, terrestrial plants absorb and emit CO2 O2. To affect either gas amounts plants need to decline or increase. Ocean chemistry changes caused bacteria changes, it being the oceans and source of most O2 by far, it is not surprising these changes were probably the final nail in the coffin, and caused by the Oman and Siberian traps and very possibly a lot of geological activity in the oceans too!
If CO2 levels dropped around 300m years ago, plant growth would have been severely impacted, plants take several generations to properly adjust to new CO2 levels to incorporate the extra gas into base growth size.
Unfortunately we need accurate beginning and termination of events to get a true picture of possible cause. We do not have that resolution, so it’s all just guesses which came first.
Too many guesses in published literature on this subject

Robert of Ottawa
August 25, 2016 2:56 am

… emitted enormous amounts of volatiles, such as carbon dioxide …
CO2 is not a “volatile”. This is just a continuation (and result) of the attempt to demonize CO2

Robert of Ottawa
August 25, 2016 3:08 am

Can anyone point me to info regarding the rapidity of these various mass extinction periods? Were they catachlismic, over-night events or took several million years? The dinosaur extinction could be explained by a successull egg-eating species. That would take millions of years, while a comet impact would supposedly cause the extinction in a year or so.

Mark - Helsinki
Reply to  Robert of Ottawa
August 25, 2016 9:08 am

I think the major problem is we can’t define the beginning and end of these events, we dont have the resolution in the data.
There is not even agreement on when the LIA started and ended never mind 250-300 million years ago.

Vlad the Impaler
Reply to  Robert of Ottawa
August 25, 2016 12:33 pm

Hi Robert,
As pointed out above and multiple places on this thread, the main problem is resolution. The further back in time one goes, the less resolution there is.
It has also been pointed out that the “extinction” was a process, starting at least several million years before the final, “terminal” event itself. What was the final ‘nail in the coffin’? Excellent question: we just do not know.
We do not know how long the “terminal” extinction took to unfold. Hypothetically, it could have been just one calendar year, or it could have unfolded over (conceivably) 20,000 years, 30,000 years, or 98,000 years, or just about any number under 150,000 – 200,000 years, as that is the theoretical limit of our best time resolution at the end of the Paleozoic. Regardless of the actual number, in a geological sense, it was “instantaneous”. The biggest problem with trying to understand geologic time is that any reference based on a human lifetime becomes meaningless. Take this issue with looking at “climate change” over the past two centuries. Elderly people today can recall weather events from (a maximum) of a century ago. Such a time frame, geologically, is not resolvable (unless we are looking at recorded human history, which is itself almost geologically close to meaningless). Certainly climate has changed over two centuries, because it is always changing.
But having apoplexy over changes on this time scale is ludicrous. Year 500,000 A. D. geologists/climatologists will probably be unable to detect what we have witnessed since C. Y. 1800, when looking at delta-O-18 isotopes.

August 25, 2016 9:24 am

Whatever happened to the proven idea that volcanism causes global cooling consequential to all of the particulates? Everywhere I look, I see these idiots grasping at straws to try and support an absurdly high sensitivity that logic, physics and data unconditionally disputes. Anyone who can’t see the dysfunctional nature of climate science caused by political intervention either isn’t paying attention or they approve of the IPCC’s strategy of using the false excuse of saving the world to justify destroying the economic prosperity driven by free market capitalism.

Johann Wundersamer
August 25, 2016 9:40 am

The mass extinction was likely triggered by a explosive event of volcanic eruptions. These eruptions lasted for a million years.
Today some scientists argue that we are facing a new mass extinction period, mostly caused by human activities.
– human activities, causing vulcanic eruptions lasting million years. Should do it.

Eugene WR Gallun
August 25, 2016 12:02 pm

A point for consideration that seems true but may be valueless.
There was one super continent. Almost all ocean life is found in the shallow waters around continents. This extinction involved both land and ocean life. I can remember reading somewhere that most life on the single continent was concentrated at its edges (maybe I am remembering wrong). If so those extinctions took place in close proximity to one another.
Just a thought probably worthless.
Eugene WR Gallun

Leonard Weinstein
August 25, 2016 1:02 pm is a link to an analysis I made several years ago showing the likely-hood of the relation of asteroid strikes to major volcanic activity such as the Deccan traps (and also likely the Siberian activity). Both dust blocking sunlight, as well as emitted gases had effects. BTW, the Deccan traps were opposite the strike 65 My ago, but the plate drift moved the location to the present.

August 25, 2016 1:33 pm

If this study is even partially right, it means extreme climate change can occur without any human involvement. How then can we be so certain that changes to the climate today are not also being caused by natural events?

Ian H
August 25, 2016 2:31 pm

An exTINTion event – as in coral bleaching maybe?
Sorry – I shouldn’t be facetious. You should fix the spelling in the heading.

August 26, 2016 2:17 pm

We really don’t know what happened that long ago.

August 29, 2016 12:21 pm

I haven’t read all the comments, but did anyone mention that LIP’s, and non-explosive (basaltic) eruptions generally also produce large quantities of HCl and HBr, both of which deplete the ozone layer and allow more UV-B irradiation of Earth’s surface, which could have led to global warming?

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