From the University of Leeds , 250 million year old certainty where there was none before, now megasized.
Tropical collapse caused by lethal heat
Extreme temperatures blamed for ‘Dead Zone’
Scientists have discovered why the ‘broken world’ following the worst extinction of all time lasted so long – it was simply too hot to survive.
The end-Permian mass extinction, which occurred around 250 million years ago in the pre-dinosaur era, wiped out nearly all the world’s species. Typically, a mass extinction is followed by a ‘dead zone’ during which new species are not seen for tens of thousands of years. In this case, the dead zone, during the Early Triassic period which followed, lasted for a perplexingly long period: five million years.
A study jointly led by the University of Leeds and China University of Geosciences (Wuhan), in collaboration with the University of Erlangen-Nurnburg (Germany), shows the cause of this lengthy devastation was a temperature rise to lethal levels in the tropics: around 50-60°C on land, and 40°C at the sea-surface.
Lead author Yadong Sun, who is based in Leeds while completing a joint PhD in geology, says: “Global warming has long been linked to the end-Permian mass extinction, but this study is the first to show extreme temperatures kept life from re-starting in Equatorial latitudes for millions of years.”
It is also the first study to show water temperatures close to the ocean’s surface can reach 40°C – a near-lethal value at which marine life dies and photosynthesis stops. Until now, climate modellers have assumed sea-surface temperatures cannot surpass 30°C. The findings may help us understand future climate change patterns.
The dead zone would have been a strange world – very wet in the tropics but with almost nothing growing. No forests grew, only shrubs and ferns. No fish or marine reptiles were to be found in the tropics, only shellfish, and virtually no land animals existed because their high metabolic rate made it impossible to deal with the extreme temperatures. Only the polar regions provided a refuge from the baking heat.
Before the end-Permian mass extinction the Earth had teemed with plants and animals including primitive reptiles and amphibians, and a wide variety of sea creatures including coral and sea lillies.
This broken world scenario was caused by a breakdown in global carbon cycling. In normal circumstances, plants help regulate temperature by absorbing Co2 and burying it as dead plant matter. Without plants, levels of Co2 can rise unchecked, which causes temperatures to increase.
The study, published today [19 October 2012] in the journal Science, is the most detailed temperature record of this study period (252-247 million years ago) to date.
Sun and his colleagues collected data from 15,000 ancient conodonts (tiny teeth of extinct eel-like fishes) extracted from two tonnes of rocks from South China. Conodonts form a skeleton using oxygen. The isotopes of oxygen in skeletons are temperature controlled, so by studying the ratio of oxygen isotopes in the conodonts he was able to detect temperature levels hundreds of millions of years ago.
Professor Paul Wignall from the School of Earth and Environment at the University of Leeds, one of the study’s co-authors, said: “Nobody has ever dared say that past climates attained these levels of heat. Hopefully future global warming won’t get anywhere near temperatures of 250 million years ago, but if it does we have shown that it may take millions of years to recover.”
The study is the latest collaboration in a 20-year research partnership between the University of Leeds and China University of Geosciences in Wuhan. It was funded by the Chinese Science Foundation.
For more information:
‘Lethally hot temperatures during the early Triassic greenhouse’ by Yadong Sun (University of Leeds and China University of Geosciences), Michael Joachimski (University Erlangen-Nurnberg, Germany), Paul B. Wignall (University of Leeds), Chunbo Yan (China University of Geosciences), Yanlong Chen (University of Graz, Austria), Haishui Jiang (China University of Geosciences, Lina Wang (China University of Geosciences) and Xulong Lai (China University of Geosciences) is published in Science on 19 October 2012. For a copy please view the web page http://www.eurekalert.org/jrnls/sci/ or contact the Science press team, phone +1 202-326-6440 or email scipak@aaas.org
For interviews please contact Esther Harward, University of Leeds press office, phone +44 113 343 4196 or email e.harward@leeds.ac.uk
Mmmmmm, Bill? Pssst, pure water boils at 212F. Pass it on. 😉
Not long ago, historically speaking, philosophers and ritualists performed the task of developing and maintaining mythologies about the world and its past. Now, the science movement has fully taken over this job of myth-creation. With no inspiration. We are reduced to insipid little sci-myths about how the gods of Gloval Varming once stalked the earh. And…shudder, they may return! O the fear!
hoppy says:
October 19, 2012 at 4:56 am
So on the one hand you have “extreme” temperatures and no fish alive in the tropics and then on the other they are sampling teeth from these same non-existent fish…..
======
Strictly speaking, they are looking at conodont “teeth” (not “skeletons”), not fish teeth. Conodonts were rather obscure creatures that apparently died out at the end of the Triassic. The seem to have some external similarities to fish, but so do the also ancient Chaetognath worms — which really are not remotely fish.
And I think they are (or think they are) looking at fossils from the cooler mid and high latitudes. (except that their conodonts are from South China which their map seems to put squarely in their “dead zone”).
There are BTW, modern fish that can handle up to 45C. Desert pupfish for one
Question: isn’t there some practical limit to the amount of warming that greenhousing can create? There is, after all, only so much infrared radiation from the Earth to intercept. Is that limit really high enough to allow land 50-60C temps?
Observation: Aliens with some fragmentary data on the modern Earth and with better climate modeling than ours might well identify us as having two mid-latitude “dead zones” with low rainfall, and brutally high Summer temperatures. Not that accurate a picture of our world I think.
I wouldn’t take this paper all that seriously.
First, they say all the plants died and there was nothing left to sequester the CO2, then they say it must have been a strange world with no animals and only–wait for it–plants. ;>
Looks to me like Yadong desperately needs more IPCC related grant funds. The troops have got to be paid if you want to save the planet from CO2. Sadly for Yadong, his fishing trip is likely to end with an empty stringer. Too bad he didn’t download the infamous Anthony Watt’s free World Climate Widget. Then Yadong might have seen the current reality storm coming.
I see two obvious flaws in Yadong’s study. First the ‘Great Dying” that happened 250 million years ago coincides with the breakup of super-continent Pangaea, which is said to have released huge quantities of methane and nitrous oxide as well as some CO2. As GHG’s, methane and nitrous oxide are many times more powerful as GHGs than CO2 — 25X and 298X respectively. Maybe Yadong considered this? I don’t know. The AAAS paywall hides the answer, from me anyway.
Second, I don’t think Yadong ever visited Texas in August. He’s talking about 120 degrees F. The Great Dying didn’t kill everything. Thirty percent of land creatures survived, and Great Dying’s survivors evolved into land vertebrates that eventually became human beings. So what’s his complaint?
.
I am unconvinced, firstly by the limited data source, and secondly by the assumptions regarding isotop/temp correlation. Add in the biological and physiological differences of animals back then (the conodonts) – which we know NOTHING about – I don’t suppose much soft tissue survived the fossilisation process (/sarc) so we don’t even know how they made their teeth!
comparing any modern processes/animals, etc with fossils is a very ‘guessing’ game, which likely gets more and more erroneous the further back in time we go. just sayin….
Plakat1 says
Second, I don’t think Yadong ever visited Texas in August. He’s talking about 120 degrees F. The Great Dying didn’t kill everything. Thirty percent of land creatures survived, and Great Dying’s survivors evolved into land vertebrates that eventually became human beings. So what’s his complaint?
Assuming he’s a watermelon, that is precisely his complaint.
.
“Jim Clarke says:
October 19, 2012 at 8:50 am (Edit)
In a few hours, readers here have literally eviscerated this paper! How does this stuff get published?”
yes and most did that without even reading it. Kinda like people who said Mann’s book was great without reading it.
Here is a clue. You can post anything with the word carbon on WUWT and people will scream no. without reading. without thinking. without being skeptical about their own skepticism.
Most funny are the people who dont understand the word “Zone’
Geologists are wrong about how the Earth got to where it is. Updated hypotheses based on Google Maps data can be found here:
http://www.threeimpacts-twoevents.com/wp-content/uploads/2012/10/SIMULTANEOUS-IMPACTS7.pdf
http://www.threeimpacts-twoevents.com/wp-content/uploads/2012/10/COMET-IMPACT14.pdf
Science, LiveScience, The Huffington Post, and assorted other publications forming the political publishing wing of a political movement are busily propagating this so-calledd study and trumpeting it as further proof of the Global Warming, AGW, and Climate Change mantra. They promote this study while not giving readers the easy access requiredd to read the study. You are in effect arguing that the proponents of the study must have every opportunity to promote public acceptance of the conclusions of this study while denying the opportunity to criticize and oppose support for the study’s conclusions so long as the study’s authors deny free access to reading the study. What you are suggesting is comparable to a referee at a boxing match demonstrating on one boxer all of the dirty tricks which the boxers must not use in the boxing match, leaving the abused boxer hanging on the ropes before the first bell is struck to begin the boxing match. No thanks. What little has been released by the authors to promote their study is enough to find critical failures before reading the full paper. Censorship of the critcism is inappropriate and not acceptable.
Thanks, Mr. Paterson. Excellent point! (October 19, 2012 at 12:03 pm) I would only add that if the abstract and press release totally miss-characterize the actual paper, then our collective criticisms would be due for a revision. Otherwise, the criticisms are generally logical and rational given what the authors and their representatives have put out to the public.
“You can post anything with the word carbon on WUWT and people will scream no. without reading. without thinking. without being skeptical about their own skepticism.”
O the contrary, Steve! Most of the criticisms are very thoughtful and many quote the article itself, which is a difficult thing to do if one does not read it. There are some who have misunderstood something in the article. Those are generally corrected by their fellow skeptics. The criticisms are generally science based. Now compare that to the criticism NPR received for allowing Mr. Watts to appear on one of their shows. I think your description above is much more appropriate for those folks and not at all appropriate for the vast majority of WUWT responders.
D. Patterson says:
October 19, 2012 at 12:03 pm
Science, LiveScience, The Huffington Post, and assorted other publications forming the political publishing wing of a political movement are busily propagating this so-calledd study and trumpeting it as further proof of the Global Warming, AGW, and Climate Change mantra. They promote this study while not giving readers the easy access requiredd to read the study.
Thank you, this needed be said. We are being bombarded with such studies where hypothesis are being trumpeted as the one and only truth, like they found the holy grail.
I wonder where from do they know that the 2 tons of rock do not come from one hot caldera?
As the CO2 concentration during the Jurassic was higher the conclusions of the study are shown to be wrong.
Steven Mosher says:
October 19, 2012 at 11:24 am
Here is a clue. You can post anything with the word carbon on WUWT and people will scream no. without reading. without thinking. without being skeptical about their own skepticism.
Most funny are the people who dont understand the word “Zone’
Here is a clue Steven: you can publish anything mentioning “global warming” and it will be accepted and trumpeted without any skeptical thinking. Most funny from people who should use skeptical thinking in their profession. This is why such studies deserve extra skeptical receptions.
If you add to this what we have learned from climategate the level of skepticism with which such studies are received is even not enough.
Steven Mosher says:
October 19, 2012 at 11:24 am
come on Steve, the subject matter of this paper has been twisted and stretched to breaking point, and presumably just create some link to CO2(?) for publishing weight!.
FFS, palaeoclimate guys argue about ice core measurements and other ‘recent’ isotope proxy temperature derivations – how the flip can anyone stretch that out more than 250 times that? and come up with some actual numbers? from fossils?
You may not be geologically savvy, but many of us are – and this is just too much of a leap. I’m not doubting temps may well have been hot, and perhaps over a decent sized tropical zone – but suggesting anything more than that is just fanciful IMHO (as a geologist).
Please provide us with a copy. I’ll be darned if I’m going to put 1 cent into the pocket of an alarmist. By the way have you read the paper and if yes can you do a post here about it? Thanks in advance.
Let us suppose that temperatures were 20 degrees or more warmer than today 250 million years ago. Let us also suppose that this rise of 20 degrees has apocalyptic effects. Let us also suppose that the climate models are correct, and that greenhouse gases unchecked will lead to temperature rises of 3 to 10 degrees. Does this mean that the catastrophic warming that science predicts will be catastrophically (but not apocalyptically) harmful for all living creatures?
Maybe not. Let me introduce you to tintanoboa. Living 60 million years ago, at 48 feet (14.5m) long and weighing over a ton, it was by far the biggest ever snake. It could swallow a large crocodile, or a small cow. According to scientists, it could only survive due to much higher temperatures than today.
Cold-blooded animals are likely to benefit from warmer temperatures.
“This broken world scenario was caused by a breakdown in global carbon cycling. In normal circumstances, plants help regulate temperature by absorbing Co2 and burying it as dead plant matter. Without plants, levels of Co2 can rise unchecked, which causes temperatures to increase.”
So where do they actually prove this statement? Did they study how CO2 breakdown [b]caused[/b] the supposedly extreme temperatures?
During that later Jurassic era CO2 was much higher in excess of 2000 ppmv. Why did not the world say broken? How is it that with all that life is full boom and lush vegetation, CO2 had not dropped to a “safe” level?
But as long as you can get “broken world” , “Lethally hot” and ” greenhouse” in there, you can be sure that the “highly respected” Science Ragazine will publish it.
“Steven Mosher says:
October 19, 2012 at 11:24 am
…………..
Most funny are the people who dont understand the word “Zone’”
Oh, Master Mosher, what is “Zone”?
Definition of ZONE
1
a : any of five great divisions of the earth’s surface with respect to latitude and temperature — compare frigid zone, temperate zone, torrid zone
b : a portion of the surface of a sphere included between two parallel planes
2
archaic : girdle, belt
3
a : an encircling anatomical structure
b (1) : a subdivision of a biogeographic region that supports a similar fauna and flora throughout its extent (2) : such a zone dominated by a particular life form
c : a distinctive belt, layer, or series of layers of earth materials (as rock)
4
: a region or area set off as distinct from surrounding or adjoining parts
5
: one of the sections of an area or territory created for a particular purpose: as
a : a zoned section of a city
b (1) : any of the eight concentric bands of territory centered on a given postal shipment point designated as a distance bracket for United States parcel post to which mail is charged at a single rate (2) : a distance within which the same fare is charged by a common carrier
c : an area on a field of play
d : a stretch of roadway or a space in which certain traffic regulations are in force
6
: zone defense
7
: a temporary state of heightened concentration experienced by a performing athlete that enables peak performance
See zone defined for English-language learners »
See zone defined for kids »
Examples of ZONE
Origin of ZONE
Middle English, from Anglo-French, from Latin zona belt, zone, from Greek zōnē; akin to Lithuanian juosti to gird
First Known Use: 15th century
Related to ZONE
Synonyms: belt, corridor, land, neck, part(s), tract, region
[+]more
Rhymes with ZONE
blown, bone, clone, cone, crone, drone, flown, groan, grown, hone, known, loan, lone, moan, Mon, none, own, phone, pone, prone, Rhône, roan, Saône, scone, sone, stone, throne, tone
2zone
verb
zonedzon·ing
Definition of ZONE
transitive verb
1
: to surround with a zone : encircle
2
: to arrange in or mark off into zones; specifically : to partition (a city, borough, or township) by ordinance into sections reserved for different purposes (as residence or business)
— zon·er noun
See zone defined for English-language learners »
Examples of ZONE
The town council voted to zone the area for industrial use.
First Known Use of ZONE
1782
3zone
adjective
Definition of ZONE
1
: zonal 1
2
: of, relating to, or occurring in a zone defense
First Known Use of ZONE
1795
zone
noun \ˈzōn\ (Medical Dictionary)
Medical Definition of ZONE
1
: an encircling anatomical structure
2
: a region or area set off as distinct
How *dare* the ignorant masses criticize *SCIENCE*! Why, some of them don’t even have PhDs!
” “Global warming has long been linked to the end-Permian mass extinction …”
No it hasn’t. Siberian Traps volcanism is a more usual suspect.
I really hope that the lack of logic and poor scientific analysis in the press release is because it was written by an English major hired on by the university press office. I expect to be sorely disappointed when the paper becomes available.
The Permian Extinction, happened later when temperatures fell by up to 8.0C and it was caused by the Siberian Traps volcanoes. A new study published recently shows this point.
http://phys.org/news/2012-10-geochemical-analysis-chinese-permian-triassic-mass.html
I favour a similar theory, which better explains the collapse of CO2 recycling.
The Tethys Sea would have been a big swamp, similar to the Okavango today, although much larger. Tectonic changes results in draining of large parts of the swamp. Leaving behind dried out vegetation, perhaps hundreds of meters thick. We know what happens to these dried out swamps, from what happened in SE Asia in the late 1990s, they catch fire from lightning strikes. Producing dense palls of smoke covering large areas. These fires burn for decades , if not centuries, making it so dark that plants can not grow. CO2 levels rise to many times their previous level from both the fires and the lack of photosynthesis.
The fires alone would raise temperatures substantially, although with a large albedo cooling from the smoke nearer to the equator and less toward the poles. So both much warmer and cooler, depending on proximity to the fires. But the extinction occurs because the smoke stops plants photosynthesizing.
Pure unadulterated speculation.
Unworthy of publication or indeed
of receipt of public funding. IMHO
This press release was deliberately written to cause the casual reader to conclude that the “dead zone” refers to the equatorial regions of the earth that were just to darn hot for life. The main carrier of this misleading imagery is the graphic. The text of the release uses the term correctly, but within a narrative that is designed to cause readers to conflate the meaning to support the agenda. That’s how sophisticated propaganda works. The words say one thing, but the imagery that the words create is something all together different. BTW, PuffHo was leading with a story on this Press Release.
Mmm gotta wonder about the carbon thing. After all the Carboniferous preceded the Permian and an awful lot of coal measures were laid down, sequestering a lot of carbon. Perhaps it would be prudent to consider how such a continental configuration might affect geostrophic currents. Also how much land was in the equatorial region and how much was in the north/south desert belts.
Yes, it is interesting that in NSW, coals at the end of the Permian cease for about 5-10 million years after the Permian-Triassic extinction. There are lots of coal measures in the Permian, then a coal gap, and the coals that appear after the gap about 10 million years later appear to be from different organisms, and are not the same quality. The organisms that produced the Permian coals had presumably died out.
There is a lot of work done on these coals, as there is a lot mining and production of these coals, and it supports the above view. Also, right after the P-T boundary, one often sees redbeds, indicative of hothouse conditions.