From PURDUE UNIVERSITY comes this stretch of a paper that looks to be nothing more than a headline grabber. Interestingly, the study covers 56 million years ago, and somehow they seem to think the atmosphere will behave the same today. Current observations say otherwise.
Evidence disproving tropical ‘thermostat’ theory
WEST LAFAYETTE, Ind. — New research findings show that as the world warmed millions of years ago, conditions in the tropics may have made it so hot some organisms couldn’t survive.
Longstanding theories dating to the 1980s suggest that as the rest of the earth warms, the tropical temperatures would be strictly limited, or regulated by an internal ‘thermostat.’ These theories are controversial, but the debate is of great importance because the tropics and subtropics comprise half of the earth’s surface area, greater than half of the earth’s biodiversity, as well as over half the earth’s human population. But new geological and climate-based research indicates the tropics may have reached a temperature 56 million years ago that was, indeed, too hot for living organisms to survive in parts of the tropics.
That conclusion is detailed in the article “Extreme Warmth and Heat-Stressed Plankton in the Tropics during the Paleocene-Eocene Thermal Maximum,” published by the online journal Science Advances and co-authored by Matthew Huber, professor in the Earth, Atmospheric, and Planetary Sciences Department at Purdue University and member of the Purdue Climate Change Research Center. Huber’s contribution focused on climate modeling and interpreting paleoclimate data within the context of modern theoretical understanding. Part of this work was performed while Huber was also at the University of New Hampshire.
The Paleocene-Eocene Thermal Maximum (PETM) period occurred 56 million years ago and is considered the warmest period during the past 100 million years. Global temperatures rapidly warmed by about 5 degrees Celsius (9 F), from an already steamy baseline temperature, and this study provides the first convincing evidence that the tropics also warmed by about 3 degrees Celsius (5 F) during that time.
“The records produced in this study indicate that when the tropics warmed that last little bit, a threshold was passed and parts of the tropical biosphere seems to have died,” Huber said. “This is the first time that we’ve found really good information, in a very detailed way, where we saw major changes in the tropics directly associated with warming past a key threshold in the past 60 million years.”
The study is unique because of the quality of the geological records utilized. Geological records from the PETM are difficult to find, especially from an area of the tropics, Huber said. The research was based on a shallow marine sedimentary section deposited in Nigeria.
“We don’t find 50-million-year-old thermometers at the bottom of the ocean,” Huber said. “What we do find are shells, and we use the isotopes of carbon and oxygen within the shells, complemented by temperature proxies from organic material, to say something about the carbon cycle and about the temperature in the past.”
Two research methods were used to judge the temperature during the PETM, one utilizing isotopes in shells, while the other examined organic residues in deep-sea sentiments. The biotic records left behind from living organisms indicate they were dying at the same time the conditions were warming.
If the tropics are not able to control its temperature and do not possess an internal thermostat, that should reshape future thinking about climate change, Huber said.
“If you say there’s no tropical thermostat, then half of the world’s biodiversity — over half of the world’s population, the tropical rainforests, the reefs, India, Brazil — these populous and very important countries have nothing to prevent them from warming up substantially above conditions that humans have been used to,” he said.
The trends in temperature increases in the tropics are similar to those found in other parts of the world, but other records have been very sparse and limited until now.
###
Huber’s work has been funded by the National Science Foundation through grants EPS 1101245 and OCE 0902882. The model used in the study is developed by the National Center for Atmospheric Research, which is also supported by the NSF. Computing was provided by ITaP’s Research Computing.
Full paper. Open Source: http://advances.sciencemag.org/content/3/3/e1600891.full
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Whose theory is that?
Footnotes. Amazing things.
I. N. Williams, R. T. Pierrehumbert, M. Huber, Global warming, convective threshold and false thermostats. Geophys. Res. Lett. 36, L21805 (2009).
Yes, reference your own paper. I remember reading the papers about global warming15-25 years ago. The same several persons, cross-referencing each other, a very tightly knit group. Sounds like it should rank with pal review.
Read the Paper Referenced. I dont do windows or change your diapers.
“I dont do windows or change your diapers.”
Perhaps you ought to learn, Mosher.
It looks like the dodgy second-hand temperature database business is going to go t1ts-up any day now, and you’ll need some way to make a crust.
Ah, but I forgot, you’re moving into the dodgy second-hand air polluton database business, aren’t you?
Forest
The footnote is ALSO attached to this
In addition, the hot tropical SSTs refute tropical thermostat theory (14).
So, you have to read the paper ( I did a while ago)
AND follow down to the footnotes
Then read the paper referenced
“[3] The aspects of tropical dynamics to be discussed here bear on the class of thermostats proposed by Newell [1979] and Ramanathan and Collins [1991], in which tropical SST is limited by either evaporation or cloud feedbacks which set in at a trigger temperature erroneously assumed to be a universal constant independent of atmospheric CO2 concentration.”
Steven Mosher:
As I prove in my post “Climate Change Deciphered”, the amount of Sulfur Dioxide aerosols in the atmosphere are the control knob for earth’s temperature.
Properly manipulating them should enable us to adjust temperatures to our liking.
“Read the Paper Referenced. I dont do windows or change your diapers.”
Since I haven’t seen evidence that anyone asked for a diaper change, I must assume that your tart tongue is being let loose yet again. Honestly, I have tired of it. Therefore, all posts with ‘Steven Mosher’ in the header will now join a fair number of others in my personal ‘ignore’ bin. Sort of a shame, really. Some of your posts have been interesting or entertaining. Too many have just been snarky and/or nasty in tone. I have attained an age where I have no urge to continue reading such. A small amount of civlity doesn’t not seem too much to ask but does seem beyond most of the children of the internet.
Anyone still reading has my full approval to add my postings to their ignore bin. I follow the inclinations of the great Rhett Butler.
Forest you have to read the paper. I believe willis has discussed it here. .Roy Spencer as well. The thermostat theory has been around.you haven’t
Forest
The paper references
I. N. Williams, R. T. Pierrehumbert, M. Huber, Global warming, convective threshold and false thermostats. Geophys. Res. Lett. 36, L21805 (2009).
That paper references this
“[3] The aspects of tropical dynamics to be discussed here bear on the class of thermostats proposed by Newell [1979] and Ramanathan and Collins [1991], in which tropical SST is limited by either evaporation or cloud feedbacks which set in at a trigger temperature erroneously assumed to be a universal constant independent of atmospheric CO2 concentration.”
Newell and Ramanthan
The latter paper was discussed in the great willisgate
http://www.drroyspencer.com/2013/08/on-the-cloud-thermostat-hypothesis/
http://www.drroyspencer.com/2013/10/willisgate-take-2/
http://www.drroyspencer.com/2013/10/citizen-scientist-willis-and-the-cloud-radiative-effect/
http://www.drroyspencer.com/2013/08/on-the-cloud-thermostat-hypothesis/
Cat
Climate is my hobby, air pollution as well.
If you look at the interglacial temperatures compared to the bottom of the ice-age, you’ll see that ice-ages have over the last 5million years been getting colder and colder, but in contrast, the interglacials remain within a narrow band.
This strongly suggests some form of limit to the climate such that temperatures cannot easily get warmer.
However, like you I’m perplexed as to what the original theory was, what the evidence supporting a tropical thermostat was and how it was proposed it functioned.
From other discussions that I have listened in on The proposed thermostat comes from the fact that as water warms up, the rate of evaporation increases. This acts as a strong negative feedback.
First the evaporation itself cools the water, secondly the extra water in the air creates more clouds.
Meanwhile, when did you stop beating your wife?
Um, when the climate stopped changing?
– I’m sorry, Senator Franken, but I’m not going to a reply to such blatant instigation.
– Ok, I’ll reword: when did you cease to assault your spouse?
– Senator, again, this is not a question…
– So you deny that you have ended your physical violation of your partner?
– Senator Franken…
– You can’t confirm or deny that you have quit striking your other half?
Forrest, i’ve heard it mentioned enough that it’s kind of “common knowledge”. (joworowski used to mention it alot) The thinking is that over the last 800,000 years, the ice ages, it’s the poles that do most of the warming/cooling. That’s why the estimated global temperature over this period is thought to be half what is indicated at the poles. (a 4C range as opposed to the 8C range as indicated at the poles) i’ve never really heard the reason why. i’ve always assumed it’s because of the presence of the thermohaline circulation. The ocean turnover keeping temps warmer/cooler at the tropics than they otherwise would be. There is even a school of thought out there that the 800 year lag in CO2 behind temps in ice cores is actually because global temps lag temps at the poles. (in other words, it would be a lag of global temps behind polar temps and not one of CO2 behind temperature)…
The poles don’t do any cooling to speak of.
The surface radiation rate generally varies with the fourth power of the Temperature, so the hottest tropical desert regions cool about 12 times faster than the coldest polar regions.
Need I say the cooling rate is highest during the hottest part of the midsummer afternoons.
G
The biodiversity of the tropics and the incredibly specialized nature of many organisms in the tropics indicates that the tropics have been ridiculously stable in temperature for many millions of years. Otherwise, these detailed and intimate interspecies dependencies would not have evolved. Vary stable, with the poles doing most of the temperature changes.
What the panicky warmists decline to mention is that a warmer world simply means a longer but not hotter summer, slightly warmer night time temperatures, a longer growing season, and milder winters.There is no indication that the summers get hotter in temperature magnitude, just in temperature average. Corn in Iowa loves 100 deg F and 100% humidity in the summer. Winter temperatures in Alberta Canada might be -29 deg F instead of -31 deg F, still cold but not as cold.
afonzarelli
March 7, 2017 at 12:51 am
Hello there..
That is your statement:
” There is even a school of thought out there that the 800 year lag in CO2 behind temps in ice cores is actually because global temps lag temps at the poles.”
————-
You may be right , but I doubt it.
Regardless of the “school of thought” you rely on….. the actual lag of CO2 IS NOT TO TEMPS…
The actual lag of CO2 is the actual lag of CO2 concentration to the Co2 EMISSIONS variation OVER TIME..
And is no so much related to time than the actual temp variation…
And wholly depends in the CO2 residence time in atmosphere…..
800 years lag in long term data is as same as 150-200 years lag in short term,,,,still the same lag as far as for the climate date……still a lag in an ~0.4C temp variation…….the data about the 300 years confirms that…. and the whole entirety of climate data supports it at any time……..
Further more as you state:
“a 4C range as opposed to the 8C range”
That is not quite correct……..according to the official orthodoxy, is like more a range of 4.5-7.5C compared with a 8-12C range….not quite the same…….
The only conclusion one can derive from this is that the discrepancy is so high that any conclusion based at such data products is of a very high uncertainty and faulty in principle……of no much value as it is or contrary to what is claimed…..
hopefully you get my point of argument……….you are wholly wrong with the way of approach and the intention to make some sense out of all this, as far as I can tell……..the classical error that most fall for, as far as I can tell…..
Hopefully this is of some help to you.. 🙂
cheers
…The research was based on a shallow marine sedimentary section deposited in Nigeria.,,,
Surely a very shallow marine area, possibly with a dark bottom, under tropical sun, might warm up to incredible temperatures. You might get boiling in small enclosed areas. But this would not be representative of the whole planet….?
Exactly what I was thinking – it’s like taking Death Valley as a proxy for the northern hemisphere today.
You won’t like my most recent article in which I more or less prove that CET is a reliable world proxy: http://scottishsceptic.co.uk/2017/03/06/temperature-reconstruction/
My thought, too. One small area of shallow water, plus the usual problems with proxies for temperature.
+1
based on a shallow marine sedimentary
Sounds like From Here to Eternity.
So, reproduce the data at another site! What is the probability of that happening even if an appropriate were discovered!!!???
an appropriate SITE (omitted above) were discovered
From the Abstract of the study: “On the basis of planktonic foraminiferal Mg/Ca and oxygen isotope ratios and the molecular proxy Tex86, latest Paleocene equatorial SSTs were ~33°C, and Embedded Image indicates that SSTs rose to >36°C during the PETM.”
WR: The proxy Tex86 seems to have a ‘very fliexible calibration’. From “A Hotter Greenhouse?” the following about the Tex86 proxy:
“Thus, a newer interpretation (see supporting online material) for the warmest Eocene suggests tropical SSTs in the 35° to 40°C range, not the 33° to 28°C range published in 2007 (9), or the 25° to 30°C range as thought a decade ago (3), or the 20° to 25°C range accepted two decades ago (2).”
Source “A Hotter Greenhouse?”: http://www.eaps.purdue.edu/people/faculty-pages/vitae/huber.pdf
28) Huber, M., A hotter Greenhouse? Science, 321, 353-354, doi: 10.1126/science.1161170, 2008 (this was a peer-reviewed, unsolicited paper)
WR: I am not a proxy specialist, but reading the above I think: “Which temperature do you want? Make one of the above choices. Might be in the 20° to 25°C range, but it might also be something in the 35° to 40°C range ……”
They used Tex86 for the temperatures. From the study:
“SSTs during the body of the PETM CIE averaged 36.1 ± 0.7°C (n = 5) based on Tex86 from the IB10B core, implying average warming of ~3°C relative to the latest Paleocene (Fig. 1C). Other TEX86 calibrations typically imply a greater degree of warming and higher maximum temperatures (see the Supplementary Materials), indicating that the Tex86 calibration–based SST change may represent a conservative estimate.”
WR: ‘a conservative estimate’ ……..
Have a look at the “supplementary material”:
http://advances.sciencemag.org/content/advances/suppl/2017/02/28/3.3.e1600891.DC1/1600891_SM.pdf
Particularly fig S5 “Bayesian TEX 86 calibrations using the IB10B data set and BAYSPAR tool”
It shows that they are 90% sure the temperature was somewhere between 30 and 50 degrees. Flexible calibration indeed.
Also I always get suspicious when the word “Bayesian” crops up, because too often it means “we couldn’t get the result we wanted, so we use Bayesian statistics where we can fudge whatever we need by using an inappropriate prior which we carefully don’t mention in the paper”.
By the way I can’t find any mention about what prior the Bayesian calibration uses in the “Supplementary Matertial”.
tty March 7, 2017 at 3:33 am
tty, I had a look at the “supplementary material”. But I stopped after “The
Red Sea is a problematic region in the modern ocean with respect to TEX86, most likely because of a
distinctly different population of Thaumarchaeota compared to the global ocean (77). The region is often
excluded from calibrations (33) because in this semi-enclosed basin, the relation between temperature and
TEX86 is notably different than in the rest of the global ocean.”
WR: Together with the Persian Arabian Gulf the Red Sea is today’s hottest sea as far as I know. When “the relation between temperature and TEX86 is notably different than in the rest of the global ocean”, how can the hot results (as shown in the study) based on TEX86 be reliable? The study: “The region [Red Sea] is often excluded from calibrations…”
How does this pass a peer review?
this makes no sense to me, I worked in hothouses in Perth WA where were were growing plants at temperatures above 50C.. staff were given 15 minutes maximum to work in there but the frogs seemed fine, the algae seemed fine, the brophytes, the helioconia’s.. all the tropical plants were growing hard and fast. Especially the algae, sitting on black plastic in pools of water that hit temps of around 60C – so much life, flourishing under these ‘lethal’ temperatures.
Maybe its just engineers, but when we want to change assumptions we need to justify it and explain the differences……..
Engineers are held to much much higher standards and are proud of those standards. The same cannot be said for the so-called “climate scientists and academics” pushing the global warming scheme.
In one of the first studies using the Tex86 proxies, the timeline overlapped the ice core record from Antarctica. The Tex86 proxies had temperatures 2C to 3C higher and there was little correlation to the ups and downs of the ice ages in the period.
Generally I am not using any Tex86-calibrated numbers anymore because they never seem to match up with known temperature history. The methodology is not used very often anymore either except when the scientists like the seemingly random results.
Dodgy Geezer:
You ask
Indeed, your question is the most important of all possible responses to the paper.
I wonder why peer reviewers of the paper did not ask your question.
Oh! Silly me! Of course I don’t.
Richard
Willis conclusively disproved. I guess he’ll never to post again. Oh, the humanity.
Everything you said is wrong. Oh, the humanity.
There was an implied “/sarc”, at least I read his comment that way.
For tropical temperature feedbacks dependent on evaporation, it should be “O, the humidity!”
Let me help you a bit with your grammar: ………. Oh, the hilarity!
Type, hit enter, proofread.
Ready, fire, aim.
Ready, fire, aim, then draw target where bullets hit side of barn.
” … SSTs rose to >36°C … ” Still does in isolated shallow pools if there is no wind, clear sky etc.Things that don’t dig in leave rather quickly. On any larger scale, the emergent phenomena kick in and it all goes steaming upwards.
“The biotic records left behind from living organisms indicate they were dying at the same time the conditions were warming.” Really?
Don’t the fossil remains primarily prove that the organisms were in fact LIVING during the time conditions were warming?
On the other hand, show me a fossil that was alive when it fossilized!
Hillary
That’s cruel, and I think you meant Nancy Pelosi, anyway.
My thoughts exactickly Tom.
G
Findings based on just one site?
Wasn’t there a tree somewhere in Yamal which had the same sort of reputation?
Pal review at its best.
“we studied samples from boreholes IB10A and IB10B and the Sagamu Quarry (SQ) from the Oshosun Formation, Dahomey Basin, Nigeria” Sounds like 3 sites. Don’t know how close.
I don’t find the word “longstanding” in the paper, neither does the paper seem to be addressing this question. That is the “media and communication” freshman writing the press release that made that up.
When the paper talks about “rapid warming” in the context of a 50 million year record ( with what time resolution ? ) rapid probably mean over a couple of million years.
When the outfit is called “Purdue Climate Change Research Center” you know that the very existence of the place is not based studying climate but trying to prop up a politcial agenda.
You would be right about that at Purdue. That particular climate research center is EXTREEMLY Liberal!! Purdue has a few slightly right of extremely left associated groups. This group is NOT one.
If they can’t settle the global temperature of the last 200 years with any kind of accuracy, anything further back should be taken with an ocean sized pinch of salt.
The researchers are basing a lot of their ‘stuff’ on data from Nigeria. That’s like a scientist 50 million years from now inferring global conditions based on data from Death Valley. Conditions in Death Valley aren’t even representative of California let alone the planet as a whole.
Nigeria is at the end of the Gulf of Guinea. Fifty million years ago the world was in a somewhat different configuration because of tectonic shifting. We don’t know how much interchange there was between the gulf and the Atlantic. Like any other shallow bay it could have been a lot warmer than the oceans*. Without any interchange with the ocean it would likely evaporate as did the Mediterranean Sea as recently as five million years ago. link
*Today’s temperatures in the gulf are delightful.
The position of the continents via tectonic shifting and the state of oceanic currents at the time vs today was one of my first thoughts when reading this ‘article’.
Also, I didn’t see it but does the author cite the studies which back up his claim that “Longstanding theories dating to the 1980s suggest that as the rest of the earth warms, the tropical temperatures would be strictly limited, or regulated by an internal ‘thermostat.’ “. Well, that and does he give any empirical range to what ‘strictly limited’ actually means? The only theories I’ve seen that ‘suggest an internal thermostat for the tropics’ are Dr Lindzen’s idea of the ‘Iris’ effect of thunderstorms in the tropics (I hope I summarized somewhat accurately) although I don’t know if he published any papers that make it a ‘theory’ and I don’t know that he has been espousing it since the 1980’s (I suspect not). If the author doesn’t he’s engaging in a classic ‘strawman’.
Interesting there is nowhere near as much scepticism going on over in the “Shock finding: P-T mass extinction was due to an ice age, and not to warming” thread. Despite research on rocks 250 million yo from a single location.
Haven’t read that one so I can’t speak to your concern.
Or one ice core (Take ya pick) or one tree, YAD061.
Read both papers and check the methodology. There is a world of difference. One is based on multiple high-precision radioisotope dates based on very well-understood physics from a number of sites. The other one on a single core, and temperatures measured by a single method of low precision (TEX 86) used far outside the empirically calibrated range.
That’s the trouble with warmists. They actually want us to reject good science to balance out our tendency to reject bad science.
PS: Tony, if you want to go over and poke holes in the science of the other paper, be my guest. With your world class skills you should be able to refute it in no time.
Is not Nigeria scam central, and the source of countless different schemes to rip off one’s money?
It is a real hot spot for it
Richard Lindzen discusses this in his video lecture Global Warming, Lysenkoism _ Eugenics
https://tinyurl.com/gpldg5f
and I’m worried. Eastasia has never advanced so far into Oceania…
Global climate studies based on the date 56 myr before the present is not very convincing analog for the present because the continents were configured differently.
https://tinyurl.com/zyaqvoy
Ocean currents were much different and the oceans occupy and occupied then about two thirds of the Earth’s surface. Then as now, the atmospheric mass was equivalent to about the mass of the top10 meters of the ocean.
The hypothesis that the Earth has no thermostat needs additional qualifications, including the configuration of the continents. And according to Shaviv and Veizer, cosmic particles also play a role.
Shaviv, Nir J., and Ján Veizer. “Celestial driver of Phanerozoic climate?.” GSA today 13.7 (2003): 4-10.
PDF of the paper: https://tinyurl.com/h6n6blr
Fred writes
No Antarctic circumpolar current for starters. The world was a very different place and our understanding of it today is worth nothing.
For example “On the basis of planktonic foraminiferal Mg/Ca and oxygen isotope ratios and the molecular proxy Tex86…”
Expectations of temperature from Oxygen isotope ratios…worthless. Quite different from our calibrations due to radically different weather patterns.
Add to that we really dont know what caused the PETM and you have way too much uncertainty to say anything useful.
Sooo…..now they can determine the temperature of things 80 million years ago to a fraction of a degree? Uhhhh….that alone tells me the whole concept is rubbish. Then, saying there is no thermostat tells me the whole concept is misconceived. The author would not know a thermostat if it were stuck in a dark place.
The entire earth is a thermostat. It radiates energy based on the temperature at the surface and the emissivity of the surface. More heat added, more radiation, which results in cooling. Less energy added, less radiation. THAT IS WHAT HAPPENS EVERY DAY AND NIGHT. To globally change temperature, it would be necessary to change the amount of energy absorbed by earth. Super volcanos, impacts, etc, could do that. Changes in the sun could do that. Changes in earth’s orbit could do that.
https://www.google.at/search?client=ms-android-samsung&q=mass+extinctions&spell=1&sa=X&ved=0
And?
JW, you must go to the site you wish to link to and copy the URL. It does not work from the search page link.
One really needs to know a bit about the PETM as a background to this paper. The PETM has long been a poster child to CAGW. A brief (c. 100 000 years) episode 55 million years ago when the world’s climate abruptly became much warmer (5 degrees or more), a sort of an ice-age in reverse. And it started from a vastly warmer climate too. Now this is something very unusual, there were a couple of similar but smaller “blips” during the Eocene a few million years later, but nothing remotely similar has happened for the last 50 million years (unless you count interglacials like the present one). And nobody knows why it happened, though it is nowadays taken as a given that it was due to more CO2 in the atmosphere, though nobody knows where it came from.
However PETM has one big drawback from a CAGW viewpoint. Nothing very terrible or even unpleasant seems to have happened. There was no mass extinction, there was as a matter of fact hardly any extinctions whatsoever, except for tropical bottom-living forams. To the contrary life on Earth seems to have flourished as it has never done since. A quite amazingly large proportion of all animal groups on Earth today first show up during the PETM, probably because the warm climate made it possible for them to disperse from continent to continent through normally uninhabitable arctic areas. There is some evidence that north American mammals became smaller during the PETM, but this was a transient effect, and it’s not that terrifying in any case. Therefore the excitement this paper has caused. There is (perhaps) actual evidence that one group of organisms were actually stressed by the PETM, at least in one place! Well, no dinoflagellates actually became extinct, but at least there were fewer of them for a while, so there.
However there is one thing that makes me suspicious. The proportion of protoperidinioid dinocysts go up sharply during the PETM, something they don’t comment on. Protoperidinioid cysts are known to be more resistant to oxidation than other dinocysts. Could the whole thing be due to differential preservation?
Nice comment. I did a bunch of research on PETM thinking it might make a nice essay for Blowing Smoke. Ended up not even writing a draft for inclusion consideration. Temps went up sharply and rapidly concommitant with injection of 13C depleated carbon. Sea level rose. 13C depleted carbon strongly suggests a fossil fuel source (Siberian coal seam fires?). But not much bad happened in the fossil record until this dubious new study. So there was global warming for ~200k years, it wasn’t anthropogenic (but may be an analog) and there was no C as in catastrophe.
I’ve tried to keep up with hypotheses about where the 13C-depleted coal for the PETM is supposed to have come from. These are the ones I’ve found (there may be more):
1. Cometary impact
2. Breakdown of oceanic gas hydrates
3. Huge peatland fires
4. The Iceland hotspot erupted through and outgassed organic deposits
5. Large scale oxidation of organic deposits on what was previously shallow seafloor in the North Atlantic
6. Large scale ocean turnover and outgassing of dysoxic deep water
7. Melting of permafrost in inland Antarctica
None of them is really satisfactory, and in any case it seems that in the best profiles warming comes first, and the d13C shift follows, not the other way around.
“Could the whole thing be due to differential preservation?” How would they know? They didn’t do a proper sedimentological analysis. Their results could be due to change in sedimentation rate or provenance, a flood in meteoric water, a facies shift, normal biological shifts, etc.
tty, notice that ristvan already mentioned Siberia. Look up the Siberian Traps, and consider what that might have done to coal deposits in the region.
Rud- The missing ingredient in your otherwise cogent analysis is imagination. With the power of imagination, all things are possible and ethics become a false barrier to the truth as “what feels right”. In the imagined future, everything that can go wrong will go wrong, unless we act today to force people to stop doing what is imagined to cause “the dreaded future”! da-da-DA!
“Look up the Siberian Traps, and consider what that might have done to coal deposits in the region.”
That was 195 million years earlier, so I should think the effect would have worn off.
There is a gulf, there is no gulf, …
https://www.google.at/search?client=ms-android-samsung&biw=360&bih=264&ei=GZ–WNLUHcKrsAHu7KzoDQ&q=the+earth+50+million+years+ago&oq=the+earth+50+&gs_l=mobile-gws-serp.
More heat = more evaporation and circulation. This would tend to slow down “temperature” increase at the equator by a significant amount, no? Why is this anymore than a local effect due to geography?
If you haven’t seen the Lindzen talk given in a link above it is very informative. Expressing his views on what and how of climate science and science in general. Never heard it put better.
How is it that the evidence can keep changing but the science remains settled?