A truly impressive paper was published this week with a new reconstruction of global temperatures over the last ~500 million years.
There is something tremendously satisfying about seeing a project start, and then many years later see the results actually emerge and done better than you could have imagined. Especially one as challenging as accurately tracking half a billion years of Earth’s climate.
Think about what is involved – biological proxies from extinct species, plate tectonic movement, disappearance in subduction zones of vast amounts of ocean sediment, interpolating sparse data in space and time, degradation of samples over such vast amounts of time. All of which adds to the uncertainty.
It is not as though people have not tried – we discussed this here in 2014, where we made a plea for better graphs of the global temperature. Now, 10 years later, we finally have something.
This work was first instigated as part of the pre-development of the Smithsonian’s Deep Time exhibit (which opened in 2019). The curators wanted a credible timeline of temperatures (including glaciations, hot house periods, extinctions, etc.) and, like many of us, had found the then-current literature somewhat unsatisfactory. There was a workshop in 2018 (that I attended) to discuss how one might go about doing something better – updating the data, improving quality control, and using models to better connect local or regional signals to the global means. Interestingly, the resulting PhanTASTIC (“Phanerozoic Time-evolving Averaged Surface Temperature Illustrative Curve”) effort was mostly privately funded. That brought in a postdoc, Emily Judd, who has been working on this ever since! The resulting paper Judd et al., (2024) (direct link) has just appeared in Science.
It’s worth talking about how this reconstruction was made. Prior efforts had been purely data based (with varying levels of corrections for non-climatic effects) and perhaps some effort to estimate global means differently depending on whether the data was from the paleo-tropics or higher latitudes. In this case however, a local temperature anomaly (inferred mostly from carbonate oxygen isotope ratios) was tied to the global mean using a set of climate model simulations for each 5 million year period (run with varying CO2 levels and with the best estimate of the paleogeography). This allowed even data sparse periods to be used to estimate the global mean temperatures (but with greater uncertainty). This kind of data assimilation is effectively a much lower dimensional process than the data assimilation that you might be more familiar with in weather forecasting, but can be quite skillful.
The resulting history back to 480 million years ago has the same broad sweep as has been seen before:
Warm temperatures prior to the Ordovician glaciation, rises of temperature through the Devonian, a dip through the Carboniferous, peaking again at the beginning of the Triassic, slightly cooler in the Jurassic, peaking again mid-Cretaceous and then (roughly speaking) cooling into the Neogene (and the last 3 million years of ice age cycles). However, the relative peaks of the warm and cold periods vary across the reconstructions, as does the scale of changes. Many of the previous reconstructions were however only for the ocean, and one would expect the global mean surface air temperature (as in this effort) to amplify that. For example, the mid-Cretaceous warming (~20ºC warmer than pre-industrial) is notably larger than in prior work.
What’s next?
As in another recent paleo paper, the authors make a partial attempt to estimate what they call an ‘apparent’ Earth System Sensitivity (ESS), this is just based on a regression of the reconstructed temperatures with reconstructed CO2. They get an ESS around 7.7±0.6ºC (95% CI). This isn’t however quite the right calculation (as we discussed in the previous post). The radiative forcing over such a long time period needs to take into account the increase in solar irradiance (about 4%) and the impacts of paleo-geography on temperature that aren’t linked to greenhouse gas changes. The first factor increases the apparent sensitivity, and the second decreases it. Additionally, the ESS is not the same as the ‘standard’ Charney sensitivity (which assumes static ice sheets) and so an ECS estimate would need to take into account the varying levels of land ice over this period and would be smaller. [It might be possible to do a better estimate with just this data… so watch this space].
What could go wrong?
This was a new and ambitious approach to a challenging problem, and there are still a lot of unaccounted for uncertainties. The prior estimate for the temperatures (based on a single, somewhat vintage, climate model) might be biased, the uncertainties in paleo geography might be important, the deep time corrections for diagenetic effects on the oxygen isotopes might be incorrect, etc. One would like to see this explored further in follow-on work – but this may take a while – the 100’s of climate model simulations took years to complete, and would take even longer with a more state of the art model.
This approach was designed for this specific long term reconstruction – not short term variability, but one could envisage an analogous effort more focused on the PETM, or the Permian-Triassic that could give more insight into geologically rapid changes.
Kudos
Nothing is ever the last word in paleoclimate, but this is a tremendous effort that really sets the methodological standard going forward. Well done to Dr. Judd and the rest of the team (and the many folks who’ve been pushing for a better reconstruction along the way).
References
- E.J. Judd, J.E. Tierney, D.J. Lunt, I.P. Montañez, B.T. Huber, S.L. Wing, and P.J. Valdes, "A 485-million-year history of Earth’s surface temperature", Science, vol. 385, 2024. http://dx.doi.org/10.1126/science.adk3705
- D.G. van der Meer, C.R. Scotese, B.J. Mills, A. Sluijs, A. van den Berg van Saparoea, and R.M. van de Weg, "Long-term Phanerozoic global mean sea level: Insights from strontium isotope variations and estimates of continental glaciation", Gondwana Research, vol. 111, pp. 103-121, 2022. http://dx.doi.org/10.1016/j.gr.2022.07.014
Wow, what an impressive research effort.
But it is downright scary to think Earth’s mean temperature has in the past been 15c higher than at present given the path we’re on.
But it’s encouraging to know that life back then was not seriously affected and even flourished when atmospheric CO2 was double what it now is.
Snark?
Or have you seriously never heard of mass extinctions and this thing called ‘evolution’ (perhaps they mistakenly call it ‘evilution’ where you come from)?
Mass extinctions were caused by things like asteroids and mantle plumes, not CO2
M. Wright Oct.14 “ Mass extinctions were caused by things like asteroids and mantle plumes, not CO2 .
Rather: “ Mass extinctions were caused mainly by volcanism through relaeasing massive amounts of CO2, directly in volcanic gases and indirectly via burning through organic matter and fossil fuels
See for instance
“ Volcanic coal-burning in Siberia led to climate change 252 million years ago
Extensive burning in Siberia was a cause of the Permo-Triassic extinction”
“The study shows that Siberian Traps magmas intruded into and incorporated coal and organic material. “That gives us direct evidence that the magmas also combusted large quantities of coal and organic matter during eruption,” Elkins-Tanton“.
What, they didn’t tell you that in your deniers summer school ? .
There is life “flourishing” in the near-boiling geysers. Does not mean that that other life that tried to lived there “was not seriously affected“. Particularly that adapting to the new environment takes a long time, the time that we don’t give to the currently living life.
And certainly humans would not thrive in the rapidly warming climate, nor will our civilization which would collapse without food production by agriculture, which in turn requires moderate, stable and predictable climate.
As a species we may have been ready for agriculture for many 10,000s of years – but we actually succeeded ONLY about 12,000 yrs ago i.e. only AFTER the great climatic upheavals of the last ice maximum and most of the subsequent deglaciation period were over. And most of our staple foods originate from moderate, not scorching hot climates.
So your being “encouraged” is either unwarranted, or disingenuous – the latter if it is a part of an old denier trope – that if some organisms thrived in the past, then so will we – and therefore we can use as much oil and gas as oil multinationals, Russia, Saudi Arabia and Iran would like us to.
— “and therefore we can use as much oil and gas as oil multinationals, Russia, Saudi Arabia and Iran would like us to.”
Another denier trope. The US is the #1 largest producer of oil and gas in the entire world bar none.
Obama did that. Trump and Biden have continued that great Oil & Gas Tradition of the Democrat Party
CJ: Trump and Biden have continued that great Oil & Gas Tradition of the Democrat Party
BPL: Democratic Party. “Democrat Party” is a pejorative term coined by GOP politicians.
Cj: “ Another denier trope.”
You_ are accusing others of denier tropes? Good one! ;-)
Cj: “The US is the #1 largest producer of oil and gas in the entire world bar none.”
the line you comment was about regimes that depend on the EXPORT of oil and gas..
The US is NOT “ the #1 largest [ NET EXPORTER] of oil and gas in the entire world bar none.“. Thus the world moving off the fossil fuels would have not been the existential threat to the US – it would be to Russia and Saudi Arabia: without the oil and gas exports – their economies would crumble, with it – their political regimes and the wealth of their oligarchs, their ability to wage wars on their neighbours and to sponsor extremists abroad.
And that’s why deniers – by fighting to stop or at least delay, the world getting off the fossil fuels – are the “useful idiots” of Russia and Saudi Arabia, By their fruits you shall know them.
P.S. This phrase does not apply to those who spread the deniers’ narratives as paid trolls of Russia or Saudi Arabia – since they are being paid to do so – they are …something, but not “idiots”…
Obama made US into a large oil and gas producer? He said “Leave it in the ground.” It was Bush and Reagan and Bush Jr. that did what you said. What oil and gas tradition of the Democrat Party? You must be kidding.
Ken Towe. Indeed there was plenty of life way back then when it was much hotter than today, but also several mass extinctions along the way, caused by rapid temperature changes. You missed that bit.
Ken T:
Back when, pray tell. Look again! Typical fake skeptic response, but the numbers don’t lie. Check the years involved.
Indeed, and when the last great city disappears under the waves of an Ocean 50 metres higher than today, life on Earth will get back to normal: without the intrusive interference of human civilization. Evidence of Homo sapiens will remain as a puzzling layer of excessively radioactive ash.
And plastic and polyhalides, don’t forget the plastic and polyhalides!
You mean polyhalogens? Those are gasses, dude. Unless you mean polyhalite which has nothing to do with the topic.
in Re to Morgan Wright, 14 Oct 2024 at 5:31 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825444
Dear Morgan,
I do not know what Dr. Ladbury meant under polyhalides. It might have been some halogenated pesticides like DDT or HCH, or halogenated persistent organic pollutants (POP), such as e.g. polychlorinated biphenyls (PCB), polychlorinated dibenzo dioxins (PCDD) or polychlorinated dibenzofurans (PCDF). These compounds are solid or liquid under normal conditions, however, they still exhibit some volatility and some solubility in water and thus slowly became ubiquitous in the environment.
Even these chemically very persistent compounds are, however, slowly degraded and mineralized in the environment, photochemically and microbially. I am therefore uncertain if they may be relevant from a geological perspective. Perhaps in glaciers might they persist for geologically relevant time spans of tens or hundreds of thousand years.
Perhaps most “promising” polyhalogenated anthropogenic organic materials could be from geological perspective polymers like polyvinyl chloride (PVC). Nevertheless, I think that even this material will be slowly microbially degraded in sediments and I am not sure if it can persist for a geologically relevant time. The best candidate could be probably fluoropolymers like polytetrafluoroethylene (PTFE). I am not aware of reports that very strong C-F bonds in this material could be microbially degraded. If so, it might perhaps indeed persist in sediments for millions of years.
Greetings
Tomáš
What there was of it. Flowering plants and mammals only show up in the last 13% of this time line.
” . . . not seriously affected . . . “?
“ . . . it is these ocean state changes that are
1:02:28 correlated with the great disasters of the past impact can cause extinction but
1:02:35 it did so in our past only wants[once] that we can tell whereas this has happened over
1:02:40 and over and over again we have fifteen evidences times of mass extinction in the past 500 million years
1:02:48 so the implications for the implications the implications of the carbon dioxide is really dangerous if you heat your
1:02:55 planet sufficiently to cause your Arctic to melt if you cause the temperature
1:03:01 gradient between your tropics and your Arctic to be reduced you risk going back
1:03:07 to a state that produces these hydrogen sulfide pulses . . . “
https://www.youtube.com/watch?v=Ako03Bjxv70
It was so hot that mammals evolved fur to stay warm.
Thank you! I saw this in the news earlier and wasn’t sure of its provenance. I don’t want to use the word ‘believe’ as it implies magical thinking, but where I cannot evaluate for myself, I trust RealClimate.
We believe things we think are true. The dichotomy between “believe” and “know” came from religion-versus-atheism disputes. There is no reason to disparage belief unless you’re using it as a club against theists. I believe E = Mc^2 because I think it is true. I can’t “know” it because I’ve never visibly converted matter into energy
Thanks. It’s hard to find the right words, but I often speak out about belief/faith because so often people are eager to condemn the scientific enterprise as a belief system in order to discredit it. Of course, to be human is to be incomplete and vulnerable to semantic issues, as language is an imperfect vehicle. [And, chortle, language itself is a belief system!]
How about “The difference between religion and science is that religion believes things whereas science temporarily accepts things while the evidence lasts.”
What about: “Religion believes in things about which there is absolutely no evidence, whereas science only believe in things for which there is a strong, solid evidence that those things actually work or are very likely to be true”?
How about Religion and Science don’t believe in either or anything.
People do.
What about: “Religious people believe things on the basis of something other than empirical evidence, while scientists at their work believe things on the basis of empirical evidence?”
I’m sorry, I have to step in here because this is getting far too religious for a scientific blog!
Belief has no real meaning in scientific debate and people try and use it to bring religion closer to real knowledge. You believe something iff it cannot be proved. By definition a god that is outside our 4d physical universe can never be proved, and so you have to have faith. There is no choice in the matter.
I don’t believe E=Mc^2, I know it to be true otherwise fusion and fission bombs and fusion reactors would not exist, and granite would not create heat and a thousand other things.
What you call belief in the scientific sense is the temporary acceptance of a working hypothesis until a better one comes along.
And Susan, it isn’t that we are incomplete or vulnerable, nothing is complete. Go and read Godel Escher and Bach if you haven’t already
KW: You believe something iff it cannot be proved . . . I don’t believe E=Mc^2, I know it to be true
BPL: You are drawing a false dichotomy. If you “know” something you also believe it.
All arguments whatsoever depend on premises at some point, and if you go far enough, those premises must be accepted on faith. This applies to the scientific method as well. We must assume empirical evidence is valid; you can’t prove empiricism empirically without arguing in a circle. Drawing a distinction between “scientists know” and “theists believe” may make you feel superior to the other, but it doesn’t accurately describe the other’s thought processes, or yours,
If something you believe is true in objective reality, it is a true belief. If you believe something which is not true in objective reality, it is a false belief. That’s the only distinction that matters.
I prefer Johann Sebastian, if you speak of Bach.
Same Bach……
https://en.wikipedia.org/wiki/G%C3%B6del,_Escher,_Bach
Keith W: Oh my, thanks for the correction, my blushes! Will take a look.
Keith,
“By definition a god that is outside our 4d physical universe…”
But we have a whole bunch of serious science folks who think it’s 11 dimensions, don’tcha know?
The point is, the problem isn’t “a god that is outside our physical universe”, but the words “outside our physical universe”. And science does in fact rely on conceptualizations that are useful but not testable.
We have instrumentation, and equations that very precisely predict the results of our measurements with those instruments. But we rely on what I think of as projections/analogies, derived from our sensory experience, to create a narrative of cause and effect that goes along with those results. (Especially in physics.) This is mostly how we figure out what the next question is.
The idea of “gods” is exactly that… mom and dad punish us and nurture us and create an environment where we can eat and sleep, so the universe must be ordered by an analogous entity.
But as old Sir Isaac illustrated in refusing to hypothesize as to what “the force” of “gravity” might be, because there would be no way to test that hypothesis, science makes use of a similar approach.
Of course, the conceptualizations in religions are not constrained… God can have whatever attribute is useful to its practitioners, which often turns out badly for the population. But I know from personal experience that I have internalized concepts (e.g. the force of gravity, or magnetic flux) in a way that could be described as “belief” when it has been useful. Of course, that faith is quickly abandoned when there is a different problem to be solved.
This seems to me a more precise way to characterize the different terms being discussed.
All of your points fall into the scientific idea I mentioned originally, i.e. “the temporary acceptance of a working hypothesis until a better one comes along” There may be 42 dimensions and people can work with that assumption if it helps the maths, but if something better gets proposed that means the universe has 4 dimensions, or 832 then we can throw away the idea of 42 dimensions.
Believe (or faith) is not like that. By definition their god is outside our ability to measure/detect/whatever
I am not putting faith down, there are many advantages to many people, but religion is the opposite of science. A scientist should abandon all previously held positions if it turns out they were incorrect. There is no equivalent in religion
KW: A scientist should abandon all previously held positions if it turns out they were incorrect. There is no equivalent in religion
BPL: There are, actually. Examples are the Protestant Reformation, the issuance of creeds, the Counter-Reformation, ,decisions by the Curia in the Catholic Church, ex cathedra pronouncements on doctrine by the Pope, the Japanese fascist actions against Buddhism in favor of Shinto (1930s-1940s), etc.
Keith,
“the temporary acceptance of a working hypothesis”
I think you are not clear on the meaning of “hypothesis”… sounds like the usual confusion with colloquial terms, like “Evolution is just a theory”.
A hypothesis is something which can be tested; hence Newton’s reluctance to go beyond his marvelous equations. In modern parlance, he was saying “shut up and calculate”. But for all our progress in science, we are still obliged to say that… we can measure and predict what happens, but we rely on untestable analogous conceptualizations, because that is how our brains have evolved to “see” the things we can’t actually see.
So when you say “the universe could have any number of dimensions”, the problem isn’t the number, it’s the word “dimensions”. How is thinking “the universe” is like a box different from thinking “God” is like a person?
Now, as to the willingness to change……seriously, do you have any idea how many versions of “religion” there are??? How many schisms upon schisms in ever smaller deviations from the previous version of whatever? Religious people change their beliefs all the time, because their “equations” are not producing the desired result for them; they may quit altogether or create their own individual construct.
I’ve already written more words than I usually like, so I will wait to see if you are understanding my position any better now.
Keith, From a Bayesian point of view, belief is not a dirty word in and of itself. Bayesian probability can be described as a “degree of belief”. It can be based on evidence, but at some point you have to start out with a Prior probability distribution. That, too, may be based on a hunch or on tangential evidence or on poor quality evidence or tangential evidence or on good evidence. The problem arises when the Prior is dominant in our conclusions–when we cannot gather directly pertinent on the proposition. That cannot be scientific in the view of a Bayesian–but there are a lot of propositions that fall into that class.
Myself, I am a Bayesian agnostic. Bayesian statistics is useful in some cases. Maybe this is one.
I would also beg people not to be so eager to condemn those of faith. The misuse of said faith is a travesty, but many scientists are well able to hold faith and work objectively in science. Attacking people puts their backs up; better to attack the ideas by providing context from the central tenets of their religion, which often contain ideas of humility, compassion, and inclusion.
BPL: We believe things we think are true. The dichotomy between “believe” and “know” came from religion-versus-atheism disputes.
Er – maybe. I have a high regard for your intellect, Barton, and I don’t wish to insult your beliefs, but according to the Stanford Encyclopedia of Philosophy (I’m not making this up, IOW), knowledge is justified true belief. AFAICT, the transgenerational, international institution of Science arose from the previously unfulfilled requirement for reliable justification of truth claims.
IIUC, religion allows us to feel confident of what we believe, without trained, disciplined empirical observation or intersubjective verification. It has unquestionably soothed private existential angst – fear of death, worry for the future, doubt about the meaning of one’s existence – for billions of people throughout history to the present. In addition, it’s an ancient mechanism of social cohesion, originally propagated orally, requiring specific, memorized beliefs to be assumed true whether epistemologically justified or not. Religious doubt must be resolved by faith: the substance of things hoped for, the evidence of things not seen. Often, though not always, there’s an element of coercion involved, top-down or bottom-up. Coercion doesn’t ensure epistemic truth, however. Again AFAICT, religion’s semantic foundation is unjustified belief.
Science, OTOH, is explicitly a method of trying not to let hope alone fool us about what’s true. It has ancient cultural antecedents, but has been globally institutionalized only during the last few centuries*. Science draws epistemic authority only from the evidence empirically seen, dismissing hope alone as not intersubjectively verifiable. It’s fundamentally a collective enterprise, not accomplished by solitary geniuses or top-down direction. It will never deliver final, complete, immutable truth. Who cares? Judged by its technological fruits alone, science is a more successful way to discern true belief from false than any tool we’ve invented since haruspicy. IMHO, Science is the most truly progressive (i.e. cumulative, shared-knowledge increasing, error-correcting, self-propagating) cultural adaptation in history.
I make no bones about my atheism, having long ago concluded theistic belief is unjustified (“I had no need of that hypothesis” – LaPlace, approximately). Regardless: by observation, not all scientists are atheists, and both religious faith and scientific skepticism coexist more-or-less peacefully in modern societies as well as individuals I care about. With respect, I leave that apparent conundrum to you and our bloggy friends. Now, back to our regular programming!
* Google’s search A.I. (“science+printing press”) identifies modern science’s origin with the introduction of Gutenberg’s printing press in the 1440s, that allowed empirical findings to be more widely scrutinized, and made both necessary training and new knowledge more accessible to any literate person.
MA: . Religious doubt must be resolved by faith: the substance of things hoped for, the evidence of things not seen.
BPL: That’s the biblical definition of “hope,” actually.
Well, I’m not really in a position to debate Biblical hermeneutics with seminarians. I was merely quoting the KJV translation of Paul the Apostle’s Epistle to the Hebrews. I gather the letter’s authorship is in doubt, but was it actually mistranslated? Are “faith” and “hope” the same word in Koine Greek? Other translations of that passage make clear it defines faith as belief without direct observation of objective evidence. Nowadays, that kind of “belief” doesn’t survive Occam’s Razor. “Knowledge” does, by being the most parsimonious explanation amongst competing ones. Surely none of this is new to you, Barton?
BPL: That’s the biblical definition of “hope,” actually.
Equivalent to the “hope” for Net Zero by 2050 followed by ZEC.
Mal,
I refer you to my comments above to Keith.
As you know, I am a strong believer in “energy”. But I can’t say that I have ever directly observed it. You might want to argue that we observe evidence of it, but that doesn’t tell us what “it” is… it is a letter, a placeholder in our equations. It is kinda-like what I feel when climbing a mountain, once I warm up, but before I get tired, or sitting and looking at my wood stove on a cold morning, so that’s the word we use.
And I take great comfort in the concept of the Block Universe, where every space-time event just… is. But who, then, am I, to judge those who say “God’s in his heaven and all’s right with the world”?
I think this “debate” about terms like faith and belief is not much use.
Zebra: “ I think this “debate” about terms like faith and belief is not much use.
Agree, the return of insight on the page posted is miserably low, and we should left it at Susan’s PRACTICAL consideration – these words should be avoided in communication of science to the public, because they open themselves to the manipulation by the deniers who would latch on these word as a “proof” that the climate change is a matter of “beliefs”
subjective and therefore not open to the test of facts and logic and as such – I “believe” in AGW is equally valid as I “don’t believe” in it.
For a similar reason (being easy to be manipulated) climate scientists should avoid “trace gas” to describe CO2 – because as demonstrated by countless deniers – the word can and will be manipulated to imply that “trace gas => trace influence on AGW”, See for instance, JCM’s attack on the climate science for: “ artificial fixation and overemphasis [on] a trace gas“.
Thus by avoiding using “trace gasses” – climate scientists would not legitimize the deniers using it manipulate the public, and the.self-identification of the deniers would be more reliable… ;-)
Mal, you were right and I was wrong–Hebrews 11:1 is defining faith, not hope. Don’t know where I got the idea it was the latter.
zebra: I think this “debate” about terms like faith and belief is not much use.
OK, z, bear with me here. Y’all feel free to talk about how knowledge and faith are alike. I’m talking about how they differ. IMHO the debate matters in the context of how BPL, you and I all know, i.e. have a justified belief, that collective action to cap anthropogenic global warming must proceed as quickly as possible under the rule of law, with the shared goal of capping otherwise open-ended aggregate costs. Put another way, our shared mental model of reality is supported by the epistemological methods of science, as a way to explain past and present observations and project probable futures that’s more reliable, i.e. has a better record of success, than gory magical rituals, laborious hermeneutics on ancient scriptures, or alleged private Christophany. IMHO the only assertion we can take on faith is that no organically evolved mind has ever possessed complete, final, absolute Truth!
In less grandiose, lower-case terms, scientifically informed beliefs about “that which, when you stop believing in it, doesn’t go away” (PK Dick), have superior epistemological justification than all previous methods of apprehending shared reality. Again IMHO, the important distinction on this blog isn’t between faith and belief, but between knowledge, e.g. the scientific consensus on AGW, as epistemologically justified belief; and faith, e.g. An Evangelical Declaration on Global Warming, as epistemologically unjustified belief. Do I need to add that AFAIK, neither BPL nor any other commenter on this thread would ever sign such a forthright repudiation of science’s most basic principles?
BPL: “ Mal, you were right and I was wrong. Don’t know where I got the idea it was the latter.”
This is, Mr. Kalisz, how a person with integrity deals with being proven wrong – no excuses, no moving the goalposts, not drifting onto a tangent, no disowning that previous arguments (“it wasn’t really an argument, it were just my feelings for which I can’t possibly be expected to take responsibility”) no trying to snatch a rhetorical victory from the jaws of the defeat, and no shooting the messenger,
If you were able to learn this – your presence on this group would not be a COMPLETE waste.
So much of the resistance to accepting the science of AGW is an epistemic fail, but if not too abstruse, maybe a better topic for the UV thread…?
Mal,
You aren’t disagreeing with what I actually said… I would have expected you to understand it better than Keith, certainly.
It seems to me that if you want to talk about metaphysics, you have to consider where the boundaries with physics get blurry. Newton was very clear about that; I thought I was doing the same, although I defer to “shut up and calculate” for its brevity.
I don’t want to repeat and take up more bandwidth; perhaps you could review my comments.
Physics works, but I at least find that I change my abstract conceptualizations depending on which calculations might have the most utility. I’ve never thought this was controversial amongst physicists. You change your “faith” depending on which problem you are solving… you don’t invoke “curved space-time” to plot the path of a basketball heading for the hoop.
Actually you did. When you eat food and use it for your metabolism you are converting matter to energy. It is just the the mass difference due to chemical bonds is much less than the mass difference due to nuclear bonds.
What the hey, I’ll chip in my 2 cents.
This seemed like a tidy way to tie up how the “big questions” are approached (paraphrasing Bob Brier):
Myths are stories out of time about the nature of reality that can’t be taken literally, whereas religion contains stories that are believed to be historical. Philosophy requires proof based on logic that is not opinion, but about facts that are nevertheless unknown.
I’ve always been comfortable, perhaps mistakenly, with distinguishing faith and belief as the former adhering to ideas that can’t be verified or proven and the later as being verifiable.
Taking Tomas, for instance, I sometimes wonder if his dogged resistance to what others are telling him, isn’t cognitive dissonance over challenges to notions of faith; something along the lines that people live on an eternal earth according to some supernatural plan or innate destiny tied to economics. Exploit the earth, go forth and multiply, manifest destiny etc. etc. whatever. It ain’t science.
RH: religion contains stories that are believed to be historical.
BPL: Strictly correct only for literalism of the Darby variety. An intelligent approach to textual criticism regards some stories as historical and others as parables or myths or songs and poetry with strong symbolic overtones.
BPL,
Makes sense. In fairness to Brier, I don’t think he was excluding those things, or philosophy, from his definition of religion.
OTOH some would argue that Buddhism is a philosophy (And that’s just a rhetorical observation on my part. I don’t want to start anything here.)
RH: “semantic issues, as language is an imperfect vehicle. [… language itself is a belief system!]”
None of us are in a position to dictate what meaning people give to words. Belief is used by people to mean different things, and there’s not a dam’ thing we can do about it. You’ve defined your terms quite nicely, but that doesn’t change how other people use language to mean stuff.
There comes a point when we have to let each person be who they are, and when it comes to matters of faith, I think there’s room for people who depend on it to look more closely at the humanistic features of their religion, and realize that the practice of science is something quite different, a learned discipline seeking objectivity from direct and measurable things.
That’s one possible take on Tomas’s stubborn resistance; I think it’s more about seeking attention, but don’t we all?
Though, to be sure, some scientific stuff is quite mind-boggling: This Black Hole Has a Cosmic Wingspan: Astronomers have discovered a black hole emitting energy in jets longer than the width of 140 Milky Way galaxies – https://www.nytimes.com/2024/09/25/science/space/black-hole-m87-energy.html
Unlocked NYT gift ink for Black Hole article ->
https://www.nytimes.com/2024/09/25/science/space/black-hole-m87-energy.html?unlocked_article_code=1.Ok4.jTT-.wiujc5xwcX0h&smid=url-share
Dennis Overbye appears to be good at science expo for laypeople. Space and time are perception stretchers.
Space and time were perception stretchers even for John Wheeler and Stephen Hawking.
Very cool!
Ray: I’m also looking for humility in the face of the vast stretches involved. Maybe a little awe and wonder, with a sprinkle of compassion, as well.
Sure, but for purposes of discussion, no matter what the subject, I think it’s fair to try and define terms with some precision. ‘Belief’ is a particularly loosey-goosey term in any colloquial usage. In fact, I edited my comment down so that I didn’t use it with more than one meaning thereby leaving it to the reader to figure out by context…
It’s nice to realize that these past high temperatures, regardless of the cause, did not create the “catastrophes” to the biota that current models predict. Even with atmospheric CO2 more than double what it now is in the late Eocene oceans the carbonate plankton diversified with a lower pH.. Plant life on land was lush. This is evidence that it’s not the rate of increase in temperature that counts. It’s the amount at the end. Today’s global temperatures are very low by comparison. That’s not scary, it’s encouraging.
I didn’t realize that the biota that exist today were the same biota from millions of years ago that survived and flourished during those past high temperatures. Thanks, I must have fallen asleep in that class.
Ken “”All is for the best in the best of all possible worlds” Towe says: This is evidence that it’s not the rate of increase in temperature that counts. It’s the amount at the end
In what logical system the observation that given LONG ENOUGH time (millions of years) some life can adapt to warmer climates – proves that the RAPID warming over decades or few centuries, i.e. not leaving life enough time to evolve – is OK, i.e. “ it’s NOT the rate of increase in temperature that counts” ?
KT: It’s nice to realize that these past high temperatures, regardless of the cause, did not create the “catastrophes” to the biota that current models predict.
BPL: Those temperatures were reached very slowly, giving life time to adapt. When temperatures changed rapidly, for instance at the End Permian event, much of the biota were wiped out,
In any case, the Mesozoic didn’t have 800 million people and trillions of dollars worth of infrastructure along coastlines.
Hi, Ken.
To back up your “encouraging” conclusion, could you please point to the geological or other evidence that indicates how the advanced civilizations prior to humans dealt with challenges like accelerated flooding of massive infrastructure along tidal waterfronts, or with the decreased oxygen in warmed waters, or how they managed to thrive despite the kind of accelerated erosion that Helene just demonstrated in the Appalachian region?
If we’re to take comfort in the past, your bland and broad statements about photosynthetic organisms don’t work for me – I confess, I’m most interested in my species and how the already-evident impacts of an increase in climate energy affect us, and I’ve noticed that 21st century humanity’s life style is vastly different from the lifestyles of plants and plankton.
Ken Towe wrote: “It’s nice to realize that these past high temperatures, regardless of the cause, did not create the ‘catastrophes’ to the biota that current models predict.”
In fact, the data shows the EXACT OPPOSITE of that. It shows that temperature changes that were both slower and less extreme than current anthropogenic warming REPEATEDLY had catastrophic impacts on the Earth’s biosphere including multiple mass extinctions.
Amazing!
Such achievements strengthen my hope that in coming years, a team or a collaboration of several teams perhaps provides also a reconstruction of past global precipitation and of the partition thereof between land and sea. As a very start, last 300 years would already represent a significant progress, as it appears that so far, only regional precipitation reconstructions are available, providing no clue yet if the precipitation partition between land and sea remains stable, fluctuates, or changes with a certain trend.
Such a global precipitation reconstruction could also provide a useful test bed for existing climate models (and a constraint for newly developed climate models), and – hopefully – help improving them.
T
Tomas Kalisz: “,i>Amazing!
Beware of Tomases bearing praise – they must have a ulterior motive. Here we didn’t have to wait long to see it – it started from the 2nd word:
TK: Amazing! Such achievements strengthen my hope that in coming years, a team or a collaboration of several teams perhaps provides also a reconstruction of past global precipitation and of the partition thereof between land and sea
WHAT FOR? “Global precipitation” is the EFFECT, NOT THE DRIVER of the climate – both today AND in the geological past. And knowing that – because we have told in reply to your 100s? of posts – you STILL want many researchers spending many years of their research life and using a lot of computing time that could have been used for more productive goals – so you and the other “anything but GHGs” deniers can misrepresent their work as supporting the claims you, JCM and Shurly weren’t able to defend using the existing scientific knowledge?
in Re to Piotr, 23 Sep 2024 at 5:53 AM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-824791
Dear Piotr,
I fully agree that precipitation is rather a climate effect than a climate driver. Although the same applies for temperature, nobody seems to question the importance of temperature reconstructions.
You will perhaps agree that precipitation cannot be unequivocally derived from temperature and that precipitation projections may be equally important as temperature projections.
That is why I think that global precipitation reconstructions, especially with respect to land/sea precipitation partition, may represent an independent and equally important benchmark for climate theory and for development of the respective modelling tools as already do global temperature reconstructions. For this reason, I do not think that investing time and effort in a global precipitation reconstruction would have been a useless enterprise.
Best regards
Tomáš Kalisz
TK: Although the same applies for temperature, nobody seems to question the importance of temperature reconstructions.
False equivalency fallacy on so many levels:
1. Temperature is good measure of the energy of the system, which drives the climate, water evaporation is NOT. Therefore, we learn much more about the past climates from past T than from past precipitation.
2. Temperature is directly involved in many important climate feedback – the glacial cycles are shaped by 4 strong positive feedbacks – T with CO2, T with CH4, T with ice/snow albedo, and T with water cycle. Of these 4 – water cycle is in any systematic way involved only with T. Therefore we learn much more about the past climates, and the therefore the current and future climates from past T than from past precipitation.
3. What we learn from the past T we can apply to our mitigation of the climate change, because humans CAN change significantly T. Humans CAN’T change by a direct intervention (i,e. not via altering T) in any significant way the global patterns of precipitation. That’s why the knowledge of the past T has implication to mitigating climate change, knowledge of past precipitation – doesn’t.
4. Because T is a single dominant factor in multitudes of biological and physical processes – it has many independent proxies. Precipitation isn’t and doesn’t. Any suggestions how are we to investigate global patterns of precipitation, cloudiness, or relative humidity, say, 425 mln years ago?
To sum up – UNLIKE past T, past precipitation patterns does not have any known methods to obtain data, and even if you had the data – you wouldn’t learn much from them – thus they would be of little relevance to predicting the future, and won’t provide actionable information to the society one its response to one of the existential problem of our civilization.
So why would ANYONE advocate a massive waste of research effort and money on THAT and diverting them AWAY from the effects of human GHG emissions???
The only group I can think of would be the fossil fuel interests, their paid “experts” and trolls, and their “useful idiots” – the “anything but the GHG” deniers, like you, Tomas Kalisz. who swallowed the fossil fuel lobby narratives for their ideological or psychological needs.
In Re to Piotr, 26 Sep 2024 at 9:26 AM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-824885
Dear Piotr,
I have not asked for a precipitation reconstruction millions years ago.
As I wrote in my post of 20 Sep 2024 at 7:36 AM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-824689
I think it would be helpful if someone was able to synthesize tens of already existing regional reconstructions covering centuries, maximally millenia, into a global one.
I think so because precipitation is important for many living organisms and for essential human activities such as agriculture. If we do not have any benchmark for testing climate models with respect to their precipitation projections, it could be one of the reasons why these tools still do not fulfil expectations put on them and why the available climate projections still have little impact on practical policies as mentioned by Palmer and Stevens in their 2019 article.
Isn’t the need to have reliable projections of the future climate not only with respect to temperature but also with respect to precipitation a sufficient reason why some scientific effort should be invested also in the above mentioned synthesis of the already available regional precipitation reconstructions into global one?
Greetings
Tomáš
TK,
I think I agree that it would be useful to have a global precipitation time series. All I can think of to produce one, though, is to integrate all the national and regional time series for that variable. In theory, you could do this yourself–look up the national products, average over the relative areas of the countries involved, and find an “ocean” product by subtracting from the estimated total precipitable water (TPW). It would be quite a project, but if you start now, you could probably have some usable data in a month or so.
Tomas Kalisz 27 Sep “ I have not asked for a precipitation reconstruction millions years ago [but the trends] covering centuries, maximally millenia”
Sure, when in response to the paper that main claim to fame is extending accurate T tracking to half a billion years . you express a “hope” that somebody will do the same for precipitation – then it is …. obvious – that you meant …. only the last “ centuries, maximally millennia“, i.e. period to which the paper brought NO NEW UNDERSTANDING (their summarizing graph has the resolution in …. MILLIONS of years)
So no, you won’t slither out on a absurd technicality that by praising the half-billion years reconstruction of temperature – you really meant the last “centuries. max. millennia”.
And to make it more pointless – all your attempts to slither out of owning up for your words – is for naught – since all my 4 points are applicable to the “centuries. max. millennia” too:
====
“1. Temperature is good measure of the energy of the system, which drives the climate, water evaporation is NOT. Therefore, we learn much more about the past climates from past T than from past precipitation.” STILL APPLICABLE to last centuries/millennia.
“2. Temperature is directly involved in many important climate feedback – the glacial cycles are shaped by 4 strong positive feedbacks – T with CO2, T with CH4, T with ice/snow albedo, and T with water cycle. Of these 4 – water cycle is in any systematic way involved only with T. Therefore we learn much more about the past climates, and the therefore the current and future climates from past T than from past precipitation.”
It applies to glacial cycles, and APLLIES to last centuries/millennia.
3. What we learn from the past T we can apply to our mitigation of the climate change, because humans CAN change significantly T. Humans CAN’T change by a direct intervention (i,e., not via altering T) in any significant way the global patterns of precipitation. That’s why the knowledge of the past T has implication to mitigating climate change, knowledge of past precipitation – doesn’t”
STILL APPLICABLE to last centuries/millennia.
“4. Because T is a single dominant factor in multitudes of biological and physical processes – it has many independent proxies. Precipitation isn’t and doesn’t. Any suggestions how are we to investigate global patterns of precipitation, cloudiness, or relative humidity, say, 425 mln years ago?”
Change “425 mln yrs” to “centuries/millennia” and you STILL have the question:
“How are we to investigate global patterns of precipitation, cloudiness, or relative humidity, say, centuries/millennia ago”?
See – you have sacrificed whatever little credibility you still had, FOR NOTHING, as it didn’t get you off the hook – all 4 points STILL APPLY.
Tomas Kalisz:
“I have not asked for a precipitation reconstruction millions years ago…I think it would be helpful if someone was able to synthesize tens of already existing regional reconstructions covering centuries, maximally millenia, into a global one.”
But that misses the point. A precipitation reconstruction going back a few centuries to a millenia still looks impossible just like a reconstruction going back millions of years would be. Anything predating reliable precipitation records based on rain gauges looks impossible, and that is anything older than about 100 years. I know of no way of inferring precipitation from materials hundreds to a thousand of years old. Do you? There are known methods of reconstructing past warming because it leaves a clear trace in various materials.
In Re to Piotr, 28 Sep 2024 at 12:20 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-824950
Dear Piotr,
on 23 Sep 2024 at 5:53 AM,
you correctly cited a sentence from my post of 20 Sep 2024 at 7:36 AM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-824689 .
It appears, however, that you somehow missed that the following sentence in my post reads:
“As a very start, last 300 years would already represent a significant progress, as it appears that so far, only regional precipitation reconstructions are available, providing no clue yet if the precipitation partition between land and sea remains stable, fluctuates, or changes with a certain trend.”
I set this goal (that may indeed look incommensurately humble in comparison with an article providing global temperature reconstruction covering a time span longer than 400 million year) just because I suppose that finding suitable proxies for past precipitation may be a harder task than finding proxies for past temperature.
With respect to your point 4, I hope that some proxies for past precipitation may exist, Besides rock paintings, there perhaps does also exist some botanical evidence that precipitation on Sahara was richer millenia ago. There might be some geological evidence in river and lake sediments. Perhaps calcium carbonate layers in stalactites and stalagmites of karst caves might contain an evidence as well. Perhaps even ice layers formed in glaciers may still contain an extractable evidence about past precipitation in mountain and/or polar regions.
With respect to your point 3 regarding climate change mitigation, I think that the knowledge of past precipitation could be useful at least as a further benchmark for developing better climate models, if not for anything else.
With respect to your point 2, I think that precipitation may be in fact involved in many feedbacks regulating temperature, and vice versa. Snow albedo may, for example, decrease with snow age and dust collection on the surface, and may be higher in case that frequent precipitation renew the fresh white surface regularly. Another example could be carbon dioxide, which can be more intensively absorbed by growing vegetation during wet seasons / in humid climates, whereas more CO2 can be released back to the atmosphere by wildfires in dry seasons / in arid climates.
With respect to your point 1, I think that not only temperature but also water cycle intensity may be an important characteristics for an actual “setup” of climate system. Works published e.g. by prof. Axel Kleidon and his coworkers suggest that various climate forcings may have a different influence on global mean surface temperature on one hand and on global water cycle intensity on the other hand.
In a summary, I still think that for us as a mankind, it can be potentially important to know not only the influence of various climate forcings on the global water cycle intensity but also what influence such forcings may have e.g. on the precipitation partition between land and ocean, and/or on regional precipitation distribution. And I still believe that the disputed global reconstruction of past precipitation – at the very start at least for last 1-2 centuries – could serve as an important support for achieving this goal.
Greetings
Tomáš
in Re to Barton Paul Levenson, 28 Sep 2024 at 11:30 AM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-824948
and Nigelj, 28 Sep 2024 at 4:23 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-824955
Hallo Barton Paul, hallo Nigel,
Thank you very much for your kind feedback.
I agree that the synthesis of the already available data as suggested by you, Barton Paul, could become the first step. Unfortunately, I do not think that I am a suitable person therefor / a person capable to accomplish this task properly.
As regards further expanding the reconstruction in the past, I agree, Nigel, that it may be challenging to find more-less reliable proxies for past precipitation, but I still hope that it is possible. I suggested a few examples which might perhaps deserve a check as possible candidates for such proxies in my recent reply of 29 Sep 2024 at 6:33 AM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-824970
to Piotr.
Greetings
Tomáš
Tomas Kalisz: “ you correctly cited a sentence from my post of 20 Sep [ about covering centuries, maximally millenia]. It appears, however, that you somehow missed that the following sentence in my post reads.
You are like Trump – who in the same breath would say two conflicting things and if the first is challenged – lectures the opponent “ however you somehow missed that [second thing] in following sentence in my post
And this avoiding responsibility for your words – is all for naught, since
all 4 of my criticisms I aimed at your “ centuries, maximally millennia” ALSO apply to your next sentence’s “ last 300 years“:
====
Piotr: “1. Temperature is good measure of the energy of the system, which drives the climate, water evaporation is NOT. Therefore, we learn much more about the past climates from past T than from past precipitation.”
STILL APPLICABLE to your “last 300 years” from your “following sentence”
“2. Temperature is directly involved in many important climate feedback – the glacial cycles are shaped by 4 strong positive feedbacks – T with CO2, T with CH4, T with ice/snow albedo, and T with water cycle. Of these 4 – water cycle is in any systematic way involved only with T. Therefore we learn much more about the past climates, and the therefore the current and future climates from past T than from past precipitation.”
It applied to glacial cycles, and it APLLIES to your “last 300 years”
“3. What we learn from the past T we can apply to our mitigation of the climate change, because humans CAN change significantly T. Humans CAN’T change by a direct intervention (i,e., not via altering T) in any significant way the global patterns of precipitation. That’s why the knowledge of the past T has implication to mitigating climate change, knowledge of past precipitation – doesn’t” – STILL APPLICABLE to your “last 300 years”
“4. Because T is a single dominant factor in multitudes of biological and physical processes – it has many independent proxies. Precipitation isn’t and doesn’t. Any suggestions how are we to investigate global patterns of precipitation, cloudiness, or relative humidity … “300 years ago”?
And as I asked before – what’s the LOGICAL connection between a paper that extends accurate T tracking to 475 MILLION years. with your call to investigate … something else for which have no reliable proxies from the past? Other that for you any pretext is good to promote your “anything but GHGs” denier’s agenda.
In Re to Piotr, 30 Sep 2024 at 9:16 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825016
Hallo Piotr,
Thank you for doing me a favour by reading not only the forst but also the second sentence of my post.
Greetings
Tomáš
P.S.
If you read to the end, you could spare repeating your four points, on which I already commented.
Tomas Kalisz: Thank you for doing me a favour by reading not only the forst but also the second sentence of my post.
Since it was you who insisted that I didn’t read the 2nd sentence and implied that it changed everything – I have shown that you lied on both accounts – I have read your 2nd sentence just didn’t refer to it because despite your claims EVERYTHING that applied to the 1st sentence APPLIES to the 2nd one as well, And because you are not the sharpest knife in drawer I have repeated my 4 points applying them for you to your 2nd sentence.
You, UNABLE to challenge any of theses 4 points, not the first time, not the 2nd – try to save your face by pretending that you already falsified them, trying deflect the attention
from your action with your attempt at irony as LAME, as you:
“ Thank you for doing me a favour by reading not only the forst but also the second sentence of my post.” Tomas Kalisz
And here are these 4 points that you presumably addressed. SInce you like referring to previous post so much – QUOTE your previous answer to each of them so everybody
can see what you claims are worth. Put your money where your mouth is, Kalisz:
=====
Piotr: “1. Temperature is good measure of the energy of the system, which drives the climate, water evaporation is NOT. Therefore, we learn much more about the past climates from past T than from past precipitation.”
STILL APPLICABLE to your “last 300 years” from your “following sentence”
“2. Temperature is directly involved in many important climate feedback – the glacial cycles are shaped by 4 strong positive feedbacks – T with CO2, T with CH4, T with ice/snow albedo, and T with water cycle. Of these 4 – water cycle is in any systematic way involved only with T. Therefore we learn much more about the past climates, and the therefore the current and future climates from past T than from past precipitation.”
It applied to glacial cycles, and it APLLIES to your “last 300 years”
“3. What we learn from the past T we can apply to our mitigation of the climate change, because humans CAN change significantly T. Humans CAN’T change by a direct intervention (i,e., not via altering T) in any significant way the global patterns of precipitation. That’s why the knowledge of the past T has implication to mitigating climate change, knowledge of past precipitation – doesn’t” – STILL APPLICABLE to your “last 300 years”
“4. Because T is a single dominant factor in multitudes of biological and physical processes – it has many independent proxies. Precipitation isn’t and doesn’t. Any suggestions how are we to investigate global patterns of precipitation, cloudiness, or relative humidity … “300 years ago”?
=================================
In Re to Piotr, 2 Oct 2024 at 7:59 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825053
Hallo Piotr,
My comments on your four points are comprised in the same post of 29 Sep 2024 at 6:33 AM.
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-824970
that you already cited separate sentences from.
I apologize for omitting the reference and copy-paste these comments herein for your convenience:
“With respect to your point 4, I hope that some proxies for past precipitation may exist, Besides rock paintings, there perhaps does also exist some botanical evidence that precipitation on Sahara was richer millenia ago. There might be some geological evidence in river and lake sediments. Perhaps calcium carbonate layers in stalactites and stalagmites of karst caves might contain an evidence as well. Perhaps even ice layers formed in glaciers may still contain an extractable evidence about past precipitation in mountain and/or polar regions.
With respect to your point 3 regarding climate change mitigation, I think that the knowledge of past precipitation could be useful at least as a further benchmark for developing better climate models, if not for anything else.
With respect to your point 2, I think that precipitation may be in fact involved in many feedbacks regulating temperature, and vice versa. Snow albedo may, for example, decrease with snow age and dust collection on the surface, and may be higher in case that frequent precipitation renew the fresh white surface regularly. Another example could be carbon dioxide, which can be more intensively absorbed by growing vegetation during wet seasons / in humid climates, whereas more CO2 can be released back to the atmosphere by wildfires in dry seasons / in arid climates.
With respect to your point 1, I think that not only temperature but also water cycle intensity may be an important characteristics for an actual “setup” of climate system. Works published e.g. by prof. Axel Kleidon and his coworkers suggest that various climate forcings may have a different influence on global mean surface temperature on one hand and on global water cycle intensity on the other hand.”
Greetings
Tomáš
Tomas Kalisz 3 Hallo Piotr, My comments on your four points are comprised in the same post of 29 Sep 2024
I have asked for the ADDRESSING my 4 points, not for a bunch of “hopes” and “maybes”.
=====
– Me: “4. Because T is a single dominant factor in multitudes of biological and physical processes – it has many independent proxies. Precipitation isn’t and doesn’t. Any suggestions how are we to investigate global patterns of precipitation, cloudiness, or relative humidity,
over either “millennia” or “300 years ago” ”
– TK: “ I hope that some proxies for past precipitation may exist”
So, if I hope that the Moon is made of blue cheese, and when asked for a proof I would reply that “I hope” that scientists will divert their research effort and computing time, to look for the proof of that”?
– TK: “ Besides rock paintings, there perhaps does also exist some botanical evidence that precipitation on Sahara was richer millenia ago.”
HOW EXACTLY do you propose to translate “rock paintings”, or even “some botanical evidence” from somewhere, into GRAPHS of GLOBAL precipitation, cloudiness and relative humidity vs time (“over the millennia”)?
– Me: “3. What we learn from the past T we can apply to our mitigation of the climate change, because humans CAN change significantly T. Humans CAN’T change by a direct intervention (i,e. not via altering T) in any significant way the global patterns of precipitation. That’s why the knowledge of the past T has implication to mitigating climate change, knowledge of past precipitation – doesn’t.”
– TK: “I think that the knowledge of past precipitation could be useful at least as a further benchmark for developing better climate models,”
And in your mind _ this_ answers my point – how? We CAN’T mitigate AGW by changing precipitation, hence data on past global precipitation EVEN IF EXISTED, are IRRELEVANT to HOW we tackle the AGW mitigation – the answer is STILL: “by reducing GHGs, NOT by increasing evaporation as you, JCM and Shurly argue”.
– Me: “2. Temperature is directly involved in many important climate feedback – the glacial cycles are shaped by 4 strong positive feedbacks – T with CO2, T with CH4, T with ice/snow albedo, and T with water cycle. Of these 4 – water cycle is in any systematic way involved only with T. Therefore we learn much more about the past climates, and the therefore the current and future climates from past T than from past precipitation.”
– TK: “ I think that precipitation may be in fact involved in many feedbacks regulating temperature, and vice versa.Snow albedo may, for example, decrease with snow age and dust collection on the surface, and may be higher in case that frequent precipitation renew the fresh white surface regularly.
To prove that it is LARGE ENOUGH to matter, compared to feedback between ice albedo and temperature – you could use modern data from a specific location.
Using the (impossible to obtain – see p.4) GLOBAL averages of precipitation is completely POINTLESS (the increase in precipitation in the REST of the globe – does not translate quantitatively into “frequency of renewal of fresh white surface” in the Arctic. Hence past global precipitation numbers are COMPLETELY INAPPROPRIATE for this goal.
– ME: “1. Temperature is good measure of the energy of the system, which drives the climate, water evaporation is NOT. Therefore, we learn much more about the past climates from past T than from past precipitation.”
– TK I think that not only temperature but also water cycle intensity may be an important characteristics for an actual “setup” of climate system.
And in your brain it ANSWERS my point – how? We are talking about DRIVING the climate, not about some nebulous “ actual climate “setup”“. Now, to be a DRIVER you have to have the ability to DRIVE – your own changes must DRIVE the changes in the climate.
Water cycle CAN’T drive, it is driven – changes in evaporation, humidity, and precipitation patterns are driven primarily by the changes in temperature, as your OWN source, Lague et al. has shown.
If you still don’t get it. let me simplify it for you: Water cycle is NOT a LEADER, it’s a FOLLOWER it does what the temperature tells it to do.
====
To sum up,
the past global T, for which we have many independent proxies) tells us much more about past climates, than the (impossible even to collect) data on past global precipitation ever could.
And for my position to be true, I need only one for these 4 points; you on the other hand, would need ALL 4. Yet so far – you got 0.
in Re to Piotr, 3 Oct 2024 at 8:08 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825080
Dear Piotr,
Thank you for your explanations. Before I reply to any of your points, I would like to clarify what we are actually discussing about.
In the penultimate paragraph of your post, you wrote:
“To sum up,
the past global T, for which we have many independent proxies) tells us much more about past climates, than the (impossible even to collect) data on past global precipitation ever could.”
I do not disprove this view, because I think that it is well possible. What I tried to express is the opinion that even if temperature is much more important characteristics of a climate than precipitation, improving the knowledge about past precipitation and its distribution could be useful, because dealing with temperature only affords necessarily an incomplete picture of Earth climate history. I still think that a less blurred picture of precipitation intensity and distribution through a few last decades (and, ideally, through at least 2-3 last centuries) could, of course in combination with already available temperature records, provide a much stronger benchmark for climate model development than so far provided the available temperature reconstructions alone.
If we mutually agree at least in this point, it could serve as a basis for a meaningful discussion about individual objections that you originally raised in your points 1-4 and recently specified in more detail.
Greetings
Tomáš
Piotr, “the past global T, for which we have many independent proxies) tells us much more about past climates, than the (impossible even to collect) data on past global precipitation ever could.”
TK “ I do not disprove this view, because I think that it is well possible.”
Aga-baga? WHAT are you trying to say? What is “well possible”? Collection of past global precipitation? If you have any reason to think so – WHY would you not share it with us HOW and by doing so DISPROVE my statement that it is “impossible”?
TK What I tried to express is that […] , improving the knowledge about past precipitation and its distribution could be useful,
To be “useful”, first it has to EXIST. HOW do you propose to MEASURE global precipitation 1000, or 300 years ago?
TK If we mutually agree at least in this point, it could serve as a basis for a meaningful discussion about individual objections that you originally raised in your points 1-4
What are you blabbering about? The first 3 points are based on the today’s climate system – so you should be able to falsify it WITHOUT ANY past precipitation value. You couldn’t.
The 4th point was – that, unlike T, you CAN’T measure global precipitation “centuries/ millennia ago”. To falsify this one you have to explain HOW do you propose to measure past global precipitation. You couldn’t.
So why would I “mutually agree” with you? Deja vu,, all over again?
– King Arthur cuts Black Knight’s legs off
-Black Knight: “All right, we’ll call a “mutually agreed” draw.”
– King Arthur : A draw? Your arms and legs are off!
– Black Knight: Tis but a scratch! If I still had my arms and legs, it could have served as a basis for a meaningful discussion about the individual objections that I lost my arms and legs that you originally raised.
King Arthur rolls his eyes moves past the armless and legless Tomas:
Black Knight: Oh, oh, I see! Running away, eh? You yellow bastard! Come back here and take what’s coming to you! I’ll bite your legs off!
in Re to Piotr, 11 Oct 2024 at 6:57 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825340
Hallo Piotr,
Thank you for your feedback.
In absence of any hint from Real Climate audience with respect to existence or non-existence of a global past precipitation reconstruction, I tried to search myself. It appears that there are some scientists that also think that reconstructions of past precipitations could be useful and strive to find out the ways thereto.
In an article “Assimilating monthly precipitation data in a paleoclimate
data assimilation framework”, Clim. Past, 16, 1309–1323, 2020
https://doi.org/10.5194/cp-16-1309-2020,
https://cp.copernicus.org/articles/16/1309/2020/
the authors write in the paragraph bridging pages 1309-1310:
“To reconstruct local millennia-long hydroclimate variability, tree-ring series were used, for example, in southern–central England (Wilson et al., 2013) and in southern Scandinavia (Seftigen et al.,2017). Pauling et al. (2006) reconstructed a 500-year-long seasonal precipitation field over Europe back to the 16th century by using instrumental measurements, documentary data, and proxy records. A reconstruction of Northern Hemisphere hydroclimate variability from multi-proxy records and documentary data is available between the 9th and 20th century
(Ljungqvist et al., 2016). A similar reconstruction was also produced for southern South America for the last 500 years (Neukom et al., 2010). Centuries-long tree-ring drought atlases are available for North America (Cook et al., 2010b), Asia (Cook et al., 2010a), Europe (Cook et al., 2015), and eastern Australia and New Zealand (Palmer et al., 2015) to study long-term hydroclimate variability. Steiger et al. (2018) produced the first global hydroclimatic reconstructions at annual and seasonal resolutions by combining multi-proxy data with the Community Earth System Model Last Millennium Ensemble model simulations (Otto-Bliesner et al., 2016) over the last 2 millennia. A multi-century global reconstruction making use of observational precipitation data is still missing.”
The Steiger et al (2018) reference “A reconstruction of global hydroclimate and dynamical variables over the Common Era” is also an open access article,
https://www.nature.com/articles/sdata201886
It appears that the proxy data the authors used include tree rings, sediments, speleothem (stalactites and stalagmites from karst caves), glacial ice, and even coral reefs and marine sponges.
Do you think that the methods these scientists already use and/or strive to further develop cannot finally bring a success in form of more accurate global precipitation reconstructions that will follow Steiger et al (2018) and that the invested effort is basically useless?
Greetings
Tomáš
Thank you for this great explainer. I was reviewing this press release (https://news.arizona.edu/news/study-over-nearly-half-billion-years-earths-global-temperature-has-changed-drastically-driven) from the Unviersity of Arizona and encountered this quote by Dr.Jessica Tierney: “We found that carbon dioxide and temperature are not only really closely related, but related in the same way across 485 million years. We don’t see that the climate is more sensitive when it’s hot or cold,”
I guess I am a little confused as to how this relates to estimating the levels of global warming we are expected to experience over the next ~100-300 years, even after reviewing your previous “Miocene” blog post.
I reviewed this other paper that Dr.Tierney was a part of, Last Glacial Maximum pattern effects reduce climate sensitivity estimates” (https://www.science.org/doi/10.1126/sciadv.adk9461). It found a modern ECS of ~3C, as expected by the IPCC consensus. I remember this paper featured heavily in discussion of global warming “acceleration” from a couple months ago. That is an entirely different topic and I look forward to following your commentary on that issue as global temps develop over the next few months. Does this new paper contradict that previous finding? Or is it really too apples-to-oranges to compare?
I hope my questions make sense. I am a complete novice regarding this topic. Thanks so much.
I’d also like to see someone more knowledgeable to speak his mind about this to be honest. One important thing to remember is that ECS is not ESS – different feedbacks, different timescales, but I’m curious how these two papers are related.
Herb (and Julian)
“I guess I am a little confused as to how this relates to estimating the levels of global warming we are expected to experience over the next ~100-300 years,”
Very little.
I’m wondering if either of you or both could answer a question… I’m not being critical at all, but I am truly curious, because you seem like the kind of people who are serious about learning: Why would you think that it does??
In my experience, it is very difficult to help people build understanding without some idea of “where they are at” in the first place. And it would be nice if there could be even a brief dialogue with people like yourselves (rather than the usual suspects here).
I think the question being asked was what we can learn about ECS from these two papers – Judd et al (2024) (with Tierney a co-author) calculating AESS [=“apparent” Earth System Sensitivity] and Cooper et al (2024) (with Tierney a co-author) which calculates S [= 150-year effective sensitivity – see the 2nd paragraph of Sherwood (2020) section 2.1 for the full description]. And ECS is relevant to how reactive the planet’s climate will be to our poking it with a sharp dose of AGW.
My take on it is that S should be considered as equivalent to ECS with Sherwood et al telling us ” This quantity therefore approximates the long‐term Charney ECS, though how well it does so is a matter of active investigation.” (I say “should be” because ECS assessments are inexact so S will be useful to nail dlwn the true value.( Thus Cooper et al present a value for “modern-day ECS” saying “the best estimate becomes 2.9°C, 66% range 2.4° to 3.5°C (2.1° to 4.1°C, 5 to 95%), substantially narrowing uncertainty compared to recent assessments.”
The AESS of Judd et al is more difficult being not immediately a true ESS and introducing the need to understand the relationship between ESS & ECS.
My understanding of the latter is that, relative to ECS, ESS accounts for changes in albedo due to melting ice caps and shifting eco-systems, processes which are normally seen as take a long time, eco-wise stuff like the northward move of the African Sahel or Siberian Taiga in a warming climate. (Mind, I’d reckon the die-off of Amazonia isn’t probably such a long-winded process.)
The relationship between ESS & ECS will vary, not least with the amount of ‘glacial feedback’ as shown in fig 2 of Passenier (2021) which suggests ESS/ECS in a range of 1.0 to 2.4 with Passenier pointing to 2.0 fitting today’s ‘glacial feedback’ which probably fits with Burton et al (2023) who calculate ESS/ECS for the Pliocene (5.4 – 2.4 My bp when the world was a little less icy than today ) at ESS/ECS = 1.7.
I’m not sure this AESS should be considered as an approximation to ESS for the full Phanerozoic. But let’s run with the idea that it is.
Judd et al are plotting their 485My global temperature reconstruction alongside a 460My log-CO2 reconstructions (as in their fig4a) and pointing out CO2 is shown (yet again) as the primary climate ‘control knob’, and quite convincingly. They then consider the sensitivity of this ‘control knob’ and use OLS thro the Paleozoic (650My-250My) data finding per doubling of CO2, +7.8°C (± 0.3°C 1sd) and thro’ the Cenozoic (66My-present) +8.2°C ± 0.4°C.
(The Mesozoic is not so useful in support of radical ‘control knob’ theory as CO2 remains relatively flat while the planet warms perhaps +10°C.)
Judd et al do make plain they are “somewhat surprised” by this “consistent relationship between CO2 and GMST across the record.” As they point out, these lengthy periods will be subject to at least solar forcing and the Land:Ocean ratio (impacting presumably surface albedo) which they attempt to quantify & plot out in their fig S.11a. The solar forcing is substantial over the full period (+9.8Wm^-2) but their assessed LandOcean effect helpfully acts in the opposite direction pretty-much the same amount thro’ the Paleozoic. For the Cenozoic (which is helpfully shorter) the solar and their LandOcean do not cancel, adding a +1Wm^-2 over the last 40My. And that adds a third on top of the CO2 forcing, a significant amount. Does that mean Cenozoic AESS should be reduced by a quarter to [0.75 x +8.2°C =] +6.15°C? And thus would suggest modern ECS = 0.5 x ESS = +3.1°C?
I’m not sure.
MA, I appreciate the detailed effort, but this sentence
“And ECS is relevant to how reactive the planet’s climate will be to our poking it with a sharp dose of AGW.”
is confusing.
I’ll assume you meant “a sharp dose of GHG increase”, but that’s what my point was in regards to Herb’s question… how does this really big fuzzy plot address the next 100 to 300 years?
We have the models based on current and projected near-term conditions… what inputs or parameters does the study tell us to change for those models?
Hi great work. How did this data relate to Milanokovic (?) cycles of warming and cooling?
John Hearps: How did this data relate to Milanokovic (?) cycles of warming and cooling?
Probably doesn’t. The long time scale (500 M yrs) comes at the price of time resolution – which is nowhere near to what would be needed to resolve the Milankovic cycles (periods 100kyrs or less)
And the climate is sensitive to Milankovic cycles only under very specific conditions – the right paleogeographic conditions and in very low CO2 concentration.
And we already know a lot about the Milankovic cycles from studies having the right time resolution – particularly in the last 800,000 yrs – as these have high-resolution and high quality data from ice cores.
Piotr: And the climate is sensitive to Milankovic cycles only under very specific conditions – the right paleogeographic conditions and in very low CO2 concentration.
Thanks. I was trying to explain this to my sister, who is intelligent but educated in the humanities. I forgot about the very low CO2 concentrations required for astronomical cycles to initiate ice ages. Amazing how Milankovitch got it right for the Pleistocene with only the science of his time. He did get support from Wegener regarding the role of continental drift, but Google’s search A.I. says:
“No, Milutin Milanković, the scientist who developed the Milankovitch cycles theory, did not have a comprehensive understanding of carbon dioxide’s role in climate change as it was not widely recognized during his time; his theory focused solely on the Earth’s orbital variations as the primary driver of ice ages, without considering the significant impact of CO2 levels.”
Sounds authoritative. Is it true?
Mal: “Sounds authoritative. Is it true?”
Probably true – given that in his time we didn’t know that much about the feedbacks resulting in the glaciation cycles.
If the amount of solar radiation in summer in Arctic increases enough to reduce amount of snow/ice compared to the previous summer – then less icy land and especially ocean will absorb more solar radiation => warmer temps => even less ice next summer and so on and on. Also the initial increase in solar radiation amplified by ice feedback, at some point start the other three positive feedbacks of T with CO2, CH4, and water cycle heating, each increasing T, and in the next cycle the higher T cause even less ice, more CO2, more CH4 and more water cycle warming.
Of these, in Milankovic time we didn’t know anything about CO2, CH4, and water cycle – feedbacks. Whether he connected the dots with melting ice decreasing water and land’s albedo – or just left at the realization that there are 3 cycles in amount/distribution of solar radiation that I don’t know. Wikipedia note suggests the latter:
“ established the astronomical theory of climate as a generalized mathematical theory of insolation ”
The ice link may have been pointed to him later, again Wikipedia:
“ He accepted Köppen’s suggestion that cool summers were a crucial factor for glaciation and agreed to calculate the secular progress of insolation of the Earth at the outer limit of the atmosphere for the past 650,000 years for parallels of 55°, 60° and 65° northern latitude, where the most important events of the Quaternary glaciations occurred.”
I don’t think his contacts with Wegener were linking continental drift with glaciation cycles – it seems to be a separate idea that Milankovic found interesting. I think the realization that you can have glacial cycles, triggered by orbital cycles, ONLY under specific conditions * came much later.
Those specific conditions are:
– that the Earth has to be cold enough to have summer ice – without it you don’t get ice-albedo feedback going (and the orbital forcing alone does not increase T enough to start the other three feedbacks). That’s why I said that “ climate is sensitive to Milankovic cycles […] in very low CO2 concentration”
– correct paleogeography – if you have continent in high latitudes instead of the ocean – Milakovic can’t trigger the ice-albedo effect.
That’s why recent glaciation cycles are triggered by Milankovic changes in solar radiation in summer in Arctic, NOT in Antarctica – Arctic is mainly oceanic – meaning that warmer than usual summer will melt sea-ice and decrease albedo; Antarctica has a continent in the centre – meaning that the ice is thick and elevated – so warmer than usual summer – doesn’t melt enough ice to expose dark water or ground, hence ice albedo feedback in Antarctica is too weak to jumpstart the other three feedbacks.
Now, because you need to get paleogeography and CO2 right – that’s why the glaciation periods are so rare – the previous one was in late Carboniferous, caused paradoxically by the success of plants in early warm and humid climate of early Carboniferous. Forests of tree ferns and tree lycophytes, after their death fell into swamps, and in low O2 mud – plant C wasn’t decomposed to CO2, but instead was sequestered in the ground, becoming ultimately coal. With so much CO2 taken out of the air, one of the condition of an ice age was met…
So ferns and lycophytes by their spectacular success, sowed the seeds of their own demise (a bit ironic since taxonomically they are called “seedless vascular plants”… ;-) ): their explosive growth changed their climate to the one in which they could no longer thrive. And when the climate ultimately rebounded, they didn’t – outcompeted by other groups, the few who survived, live today in shadows of their conquerors.
Perhaps a lesson for us…
Or at least – for the modern day Candides who are so pleased to notice that: “ It’s nice to realize that these past high temperatures did not create the “catastrophes” to the biota that current models predict. “
I think we have understood for a while that coal produced during the Carboniferous period was due to the lack of organisms that were able to decompose lignin, before fungus evolved to do so. Lignin was a new molecule when large trees evolved, before then the tallest plants were made of cellulose and hemicellulose. The lignin allowed trees to be taller but it wouldn’t decompose so it turned to lignite and morphed into harder coal.
I think we have understood for a while that coal produced during the Carboniferous period was due to the lack of organisms that were able to decompose lignin
Possibly. But that’s a minor detail – my argument does not depend on the specific cause of lack of decomposition of the masses of dead lycophyte and fern wood produced in the 1st half of Carboniferous – only on its effect – decrease in Co2 making late Carboniferous glaciation possible.
Fascinating development. Very much worth following the link back to the published paper.
Thanks, Gavin!
It’s so good that all the usual lobbyists and ignorami have rushed to traduce it.
The solution- brace and stick to X, the comedy of manners formerly known as Twitter, where diversity of opinion on climate and energyis at once deplored and needed.
Thanks for highlighting this important paper! In perspective, the Holocene that nurtured civilization is a rare climatic oasis indeed. This deep time perspective underscores the obscene risks humanity is taking by burning up our stores of fossil carbon in an absurdly short time frame.
We need to burn massive amounts of fossil stores, how else are we going to put the CO2 back into the air where it belongs and has always been?
EXCELLENT. THANK YOU.
We now need climate scientists to advise on the impacts of actions policy makers might take to save Earth’s biosphere from excessive GHGs in its atmosphere.
–
Specifically:
1) The paper concludes that the temperature response to a doubling of CO2, (including fast and slow feedbacks) of ∼8°C. Given this, what be the long-term equilibrium if Net Zero is achieved by 2050 on different plausible pathways.
2) Advising on the impacts of different geo-engineering options which could improve the post 2050 climate.
Of these:
– Carbon Dioxide Removal has a role but will be too slow to save us from severe deterioration of the climate.
– What impact’ might action to re-establish the Arctic Ocean sea ice have? (*Ideas of pumping sea water iinto the air in winter near the north pole so as to thicken the ice-cap.) https://www.climaterepair.cam.ac.uk/refreeze
– What impact would a sun-shield at the L1 point between the Earth and the Sun. have?
Regarding the sun-shield at the L1 Point:
– The UK Royal Society’s 2009 paper on geo-engineering dismissed space-based sun-shields as being too expensive and taking too long to put in place. Since then the development of large re-useable rockets (Spaceship and New Glenn) promises to remove both these constraints. by bringing down the cost of transport from Earth to the L1 point and increasing capacity to launch mass into space by a couple of orders of magnitude
– NASA’s Advanced Composite Sail research provides a basis for developing the satellites needed https://www.nasa.gov/mission/acs3
– Space-based avionics have developed to a point where low-weight avionics can manage a constellation of 6,000+ satellites.
I am by no means original in stating that a sun-shield or other geoengineering to shade the Earth would be an extremely desperate way to cool the Earth. Stopping the increase of CO2 would have a much less harmful impact.
A. High concentrations of CO2 would lead to extinctions of many marine animals from ocean acidification. Indeed, this process has already started.
B. Decreasing sunlight on the Earth would also decrease photosynthesis, decreasing plant growth and conversion of CO2 to C + O2.
Congratulations to Judd et al.
I saw the sensitivity they calculated and wondered how people here would respond.
I’ve only had a quick look at the paper, but have some skepticism. Direct estimates from marine samples are only available for periods younger than about 150 million years. So 2/3 to 3/4 of the globe doesn’t have samples to ground truth the work. The marine samples that are available are almost all from inland seas, not the same thing as the ocean.
Nevertheless, it is a step forward.
Congratulations to Dr. Judd and her entire team for producing a worthy work garnering the notice and praise it is receiving. Haven’t chewed through the entirety yet, but as Susan Anderson aptly noted: “ …but where I cannot evaluate for myself, I trust RealClimate.”
It will be interesting to see what happens when folks are able to try using this work in regards to the efforts studying the biodiversity booms and busts for this 485 million year period (beyond the Big Five.)
I can already hear the denial proclamations coming: “see, no worries!” “Drill, baby, drill!” and just generally the “Told ya! This proves [insert various inane denier conspiracy claim here]”
When the average paleo global temperature was above 35C (or 90F), how was that distributed latitudinally? Was it then well-above 100F at the equator, while still quite warm near the poles year-around?
Paleoclimatology may be similar to geology at getting to a fundamental understanding : “Geology is like trying to learn about barley by studying beer” — https://geoenergymath.com/2024/09/23/amo-and-the-mt-tide/
To your question, Paul:
https://www.sciencedaily.com/releases/2010/08/100824132417.htm
(“How giant tortoises, alligators thrived in High Arctic 50 million years ago”)
Not a complete answer, by any means, but definitely bearing on methodological and substantive aspects.
Hey, so–it looks like were in a cold spell as of late, correct?
It looks like such cold spells are essential for a complex civilization of humans to thrive, also.
Let us be thankful that winters come as frequenly as they do. Can anyone point to a paper on cool climate refugia in the intersnowball eras? Nowadays we look to places like Tibet and the uplands of Alaska for ice age survivals
Good question, Russell. I just spent about an hour hunting for the specific reference without success before falling back on memory (but try Out of Thin Air: Dinosaurs, Birds, and Earth’s Ancient Atmosphere by Peter D. Ward). A while back someone, maybe Ward, suggested that species of the therapsid Lystrosaurus that survived the PT extinction were pre-adapted to low sea-level oxygen levels at that time, by having evolved at high elevations where the air was always thin and cool. Surviving species would have been those that made their way into the lowlands just prior to the volcanic upheavals that caused drastic global warming. They would have had to survive very high ambient temperatures OTOH, which they may have escaped by burrowing. During the global low-oxygen intervals, O2 partial pressure at high elevations did not permit any vertebrates to survive, while high temperatures (and perhaps H2S toxicity) at sea level, combined with low PO2, extinguished about 2/3rds of large animal species. Higher latitudes may have been refugia for animals that could cope with low PO2.
Plants, less affected by low PO2 than animals, may have found high elevation, as well as high latitude, refugia from lethal heat. It looks like even in tropical lowlands, however, plants faired better than animals. Check out A hidden cradle of plant evolution in Permian tropical lowlands in Science.
Thanks for stirring me to at least that much effort. If you follow up on your own, let us know what you find.
Mal: “ suggested that species of the therapsid Lystrosaurus that survived the PT extinction were pre-adapted to low sea-level oxygen levels at that time, by having evolved at high elevations where the air was always thin and cool.
From the graph above it seems that while there was smaller drop in T before the PT extinction, it was immediately followed by several times bigger warming, so evolving in “cool” environment wasn’t necessarily helpful…
And evolution in a thinner air – may have helped them only in competition against …. other therapsids. Their main evolutionary competitors – reptiles, being not endothermic, needed much less oxygen per unit weight than therapsids, while the warmer climate nullified most of the advantages of therapsid endothermy.
So not surprisingly that after the PT debacle – it is the reptiles who emerged winners. And ruled the Earth for the entire Mesozoic, with therapsids and then mammals, reduced to few and unimpressive representatives – the largest mammal at the end of the Mesozoic was probably the size of a cat …
Not sure what you’re asking (now why do I suspect you already have answers). But you did make me curious.
Don’t know if one or the other of these (or neither) addresses the question..
Slushball refuges?
(Looking for primitive life before the Cambrian explosion ~500 mya, no?)
https://www.nature.com/articles/s41467-023-37172-x
Or at the other extreme…
End Permian/Triassic extinction refuges?
There were refuges in the arctics of the time–obvious enough. Perhaps more interesting, is some discussion of reef migration here:
https://www.sciencedirect.com/science/article/abs/pii/S0031018217302213
Correct, and not news, either. But “as of late” accounts for something like 3 million years, which means that current life has had time to become well-acclimated to the “cold spell.” That’s adaptation time that we are not affording the biosphere this go-round.
It’s about the timeline; trying to exploit this is a fool’s game for the gullible. Due to compression the final uptick is almost invisible, but comprises the entirety of the recent and shocking global heating. If you are interested, a couple of recommendations, the delightful A (Very) Short History of Life on Earth by Henry Gee will flesh out the perspective.
https://royalsociety.org/medals-and-prizes/science-book-prize/books/2022/a-very-short-history/
And if you like depth the somewhat grim (and loooong) Frankopan’s The Earth Transformed: An Untold Story is massively informative. – https://www.theguardian.com/books/2023/mar/02/the-earth-transformed-by-peter-frankopan-review-history-through-a-different-lens
tl;dr synopsis: comparison with other ages of the last 450 million years will tell you human habitation on earth evolved in a relatively hospitable period of its history. You (and we) would not enjoy (or survive) those warmer periods.
“A (Very) Short History of Life on Earth” is such a good recommendation. It was one of the books I read while I was trying to make sense of the problems we have as a species, the other being “A Darwinian Survival Guide” by Daniel Brooks and “Ishmael” by Daniel Quinn. Both are fantastic reads that really do put things in context (namely, why agricultural civilization just isn’t a solution to any problems we’re facing and never was – and what can we do about it).
“Due to compression the final uptick is almost invisible,”
The authors must have a sense of irony if not humor to have arranged the one pixel per 100,000 yeas, / ten eons per pixel resolution rendering in Science
https://x.com/RussellSeitz/status/1839758711226605632
Something looks very wrong with that graph. Why would modern warming with 425 ppm CO2 be anything comparable to times when CO2 was 2000 ppm?
M. Wright: Something looks very wrong with that graph. Why would modern warming with 425 ppm CO2 be anything comparable to times when CO2 was 2000 ppm?
Except that “when CO2 was 2000 ppm” is an exception, not the rule – perhaps 15 mln years out of 455mln.
So something may indeed be “very wrong”, but not necessarily with “that graph”.
Although there are many aspects of. the temperature curve similar to previous studies, it does have more warm-end variability and hotter temperatures, especially near 90 Ma (see their supplemental figure https://postimg.cc/68vcjth2) which is interesting. I’m interested in playing around with a GCM soon to see how you can get global temps up to 35-40 C with reasonable boundary conditions during this interval (in the Fast-Atmosphere Ocean Model that Gary Russell has run at GISS it happens between 8-16x CO2, but with modern continents and solar flux https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2013GL056755). There’s also interesting implications for habitability and heat stress, especially in the tropics (even in the age of mammals this is some fruitful territory to explore).
There are also a few (likely minor) things not modeled in the prior, including a slightly evolving length of day from ~22 to 24 hours, and atmospheric O2 levels. For example, an atmosphere with 30% oxygen and present-day N2 mass would have a surface pressure of over 1150 mb and broaden the absorption features of GHGs. But these can also affect their sensitivity estimate, which isn’t quite right for the other reasons too. They do try to calculate the other forcings (their supplemental S11 but I don’t think that carried over to the ESS regression)
@Paul they do show results for the pole-to-equator temperature gradient (their Fig. 3) which does indeed flatten in hothouse climates as we expect.
Take a good look at this image from the article: https://www.realclimate.org/images/graph-from-scott-wing-620px.png
In roughly a century, we’ve gone about halfway towards the “no ice caps” tipping point.
That’s horrific.
Say we hit the “no ice caps” line in 2100. How long before 1/2 of the Antarctic ice cap has melted? After 2100, how much CO2 and CH4 will humans be adding to the atmosphere? If it’s “not much”, how long will it take for those to dwindle back to present levels? Back to pre-industrial levels? Will the earth then go back below the “no ice caps” line, and if so, approximately when would that happen?
Hairy Butler: – “In roughly a century, we’ve gone about halfway towards the “no ice caps” tipping point.”
Why worry about that? I’d suggest the first metre of sea level rise (SLR) will be catastrophic to coastal infrastructure and properties around the world. Some projections suggest one metre of SLR, relative to the year-2000 baseline, appears to be likely to arrive sometime in the second half of this century.
In the YouTube video titled sea level rise – is Greenland beyond its tipping point?, published 29 Jul 2024, duration 04:19, glaciologist Professor Dr Jason Box, from the Geological Survey of Denmark and Greenland, said from time interval 0:01:50 (bold text my emphasis):
“Now if climate continues warming, which is more than likely, then the loss commitment grows. My best guess, if I had to put out numbers; so by 2050, 40 centimetres above 2000 levels; and then by the year 2100, 150 centimetres, or 1.5 metres above the 2000 level, which is something like four feet. Those numbers follow the dashed-red curve on the IPCC’s 6th Assessment, which represents the upper 5-percentile of the model calculations, because the model calculations don’t deliver ice as quickly as is observed. If you take the last two decades of observations, the models don’t even reproduce that until 40 years from now.”
https://youtu.be/8jpPXcqNXpE?t=110
The rate of global mean SLR is currently (i.e. in 2024) around 5 mm/year (per the World Meteorological Organization’s recent report titled State of the Global Climate 2023, Figure 6). I would not be at all surprised to see the rate of SLR accelerate to 10 mm/year sometime in the 2030s, and accelerate further to 20 mm/year perhaps in the late-2040s.
The impulse-response-like “spike” at the Ordovician glaciation appears anomalous somehow. The presence of ice caps seems to create a quasi-stable climate state for approximately 10^8 years. I would guess that this is primarily driven by continental drift in which the poles are over land. The absence of oceanic currents would allow the formation of ice caps and other “short time scale” phenomena such as ice ages. The cause of the Ordovician glaciation seems inconsistent with this idea. It would be very interesting to see a more detailed comparison of polar land configurations especially at the ~260 million and ~360 million crossing points as well as the 445–444 Ma.
It’s also very striking how well periods of mass extinction coincide with these crossings. This is perhaps obvious but not something I can recall hearing. The extinctions at 445–444, 372–359, 252 and 201.3 Ma. align well with these transitions. The anomaly here is the Cretaceous extinction at 66 Ma which doesn’t seem to fit into this picture. One could conclude that extinctions arise from “extreme’ temperature changes (on a geological time scale) and not on temperature levels per se.
In “Otherlands” Thomas Halliday explain this by the rise of the first land plants and land fungi increasing weathering. This would have drawn carbon dioxide from the air cooling down the climate.
There may be a cure for too many humans on the planet and emitting too much gas.
The coming microbial crisis: Our antibiotic bubble is about to burst
Andreas J. Bäumler https://orcid.org/0000-0001-9152-7809Authors Info & Affiliations
Science
19 Sep 2024
Vol 385, Issue 6715
DOI: 10.1126/science.ads3473
Scott, yes we are in a cold spell relative to the extended hot spell millions of years ago. However it looks like we wont be in a cold spell for very long. Anthopogenic warming has already increased approximately one degee C above pre industrial, and it is projected to increase to 3 – 5 degrees by 2100 and about 6 – 8 degrees after three centuries , (all at BAU scenario). It could be more than 8 degrees after thousands of years based on the long term ESS (earth system sensitivity) response..This means SLR would be 1 – 2 meters by 2100, maybe 3 – 6 metres after three centuries and in the tens of metres over millenia time frames..This all has profound implications.
We have probably already done enough mitigation work already to reduce all this slightly, but we are not doing nearly enough mitigation to adequately resolve the problem or to keep warming below 2 degrees. We need more strenouus efforts to develop renewable energy and electricy the transport system and develop viable carbon sequstration and reduce our levels of energy use (within reason)..
Of course its not really the prevailing temperature that is the main issue. Its the rate of change, and anthropogenic warming is causing rapid change, and past history suggests this is when you get the mass extinction events, because species dont have enough time to adapt ( to rapid warming or cooling). This affects not just human lives, but our farming productivity, all our trillions of dollars of infrastructure. especially coastal infrastructure, and a variety of other species.
Climate change is already costing humanity money and resources, insurance premiums are going up, people lives have been damaged, and this is just a taste of what could be coming. The climate is non linear, so things may get worse at an accelerating pace, and we could pass various tipping points making it even harder to fix the problem.. This is what worries me.
Nigel, if , on top of the ~1.5 ºC warming America has experienced in its first 250 years , you expect six or ºC or more in the 250 to come , it may not be too late for you to reconsider the moral calculus of mitigation in the light of its system of government. Considering how very little the Department of Homeland Security has accomplished globally in a generation , it might be cost effective at the margin to replace it with a Department of the Exterior charged with following up on Benjamin Franklin’s observation that Colonial land use had brightened the Western Hemisphere.
While albedo change is a slow business it might be rendered less volatile physically and politically than radiative forcing by anthropogenic atmospheric change, if only because like politics, all albedo change is local.
In Re to Russell Seitz, 2 OCT 2024 AT 4:38 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825047
Dear Russell,
Could you explain your note of Benjamin Franklin’s observation on Western Hemisphere albedo? Or add some references?
I have never heard about it and would like to know more. And, could you also add more specifically how the proposed Department of Exterior should follow-up thereon?
Thank you in advance and best regards
Tomáš
In Franklin’s Observations Concerning the Increase of Mankind he observes:
we are, as I may call it, Scouring our Planet, by clearing America of Woods, and so making this Side of our Globe reflect a brighter Light to the Eyes of Inhabitants in Mars or Venus,
CF:
William Clarke’s Observations On the late and present Conduct of the French, with Regard to their Encroachments upon the British Colonies in North America. … To which is added, wrote by another Hand; Observations concerning the Increase of Mankind, Peopling of Countries,&c.
Boston: Printed and Sold by S. Kneeland in Queen-Street. 1755.
in Re to Russell Seitz, 6 Oct 2024 at 12:11 AM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825126
Dear Russell,
Thank you very much for the reference!
Unfortunately, as I has not read Franklin’s book, it still remains unclear to me:
– if he considered land deforestation as a positive / desirable effect of human activities, or just tried to point to the fact that human activities change the entire planet on a scale that might be observable from space, and
– what you infer from his observation with respect to the foreseen scope of activities of the new (or second??) Department of the Exterior proposed by you.
I must also admit that even after your reply to my question, your sentence
“While albedo change is a slow business it might be rendered less volatile physically and politically than radiative forcing by anthropogenic atmospheric change, if only because like politics, all albedo change is local.”
still sounds cryptic to me and I am still quite unsure how I should construe it.
Could you help once again and clarify?
Thank you in advance and best regards
Tomáš
in Re to Russell Seitz, 6 Oct 2024 at 12:11 AM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825126
Dear Russell,
Perhaps you missed my additional questions of 7 Oct 2024 at 5:51 AM, or were too busy to answer.
Nevertheless, I still think that your post of 2 OCT 2024 AT 4:38 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825047
is interesting but indeed deserves a clarification.
Could you try?
Best regards
Tomáš
Link to the Benjamin Franklin paper. The quote is in the last paragraph:
https://learninglink.oup.com/access/content/schaller-3e-dashboard-resources/document-benjamin-franklin-observations-concerning-the-increase-of-mankind-people-of-countries-etc-1751
Russell Seitz: “ While albedo change is a slow business it might be rendered less volatile physically and politically than radiative forcing by anthropogenic atmospheric change, if only because like politics, all albedo change is local.”
I am not sure I follow. All politics being local means that politicians “need local skills to win the primary election that gets them into their safe seat”. How is this a parallel to climatological effects of …. a slow albedo change?
And the main change in albedo – melting of the sea ice in the Arctic and change in cloudiness due to global warming – are … “all local”?
And how exactly : “albedo changes are rendered less volatile physically and politically than radiative forcing by anthropogenic atmospheric change,”?
Jonathan, I seem to recall that one reason the Ordovican is “different” is that there were no land plants to speak of. So no land vegetation feedback or carbon sequestration, specifically on the continental shelves which would have been bare rather than being vegetated in tropical and temperate regions, once sea level fell. That must also have had an impact on weathering and erosion, e.g. more CO2 absorption and delivery to the oceans.
Also most agree that the trigger was a Large Igneous Province, with aerosol cooling followed by warming as the dust and aerosols rained out but the CO2 hung around. By definition that’s going to be a short duration event (millions not tens of millions of years).
The earlier comments about absolute CO2 level and continental configuration probably bear on why later LIPs were different and did not trigger a pre-warming Ice Age.
There are some papers which have suggested a eustatic sea level fall prior to the warming, which might indicate a localised glaciation big enough to have an impact but fortuitously located where evidence in the geological record has been lost (e.g. on high ground where the evidence was eroded). I remember being sceptical because most of the sites were close enough to the LIP to be affected by loading and flexural-isostatic effects, which would look eustatic because you’d see the same relative uplift over 1000-km ranges.
I want to point out that liverworts (Marchantiophyta) existed in the Ordovician. There were land fungi and likely lichen too. These may have been limited to the wettest areas. Anyway, they would not have produced much in the way of biomass.
Oops, the final paragraph was about the end-Permian, where majority opinion is that there was no Ice Age, despite presumably much the same continental configuration as in the Carboniferous-early-Permian Gondwana Glaciation. Judd et al, does show a short cooling spike, but on a Coolhouse baseline not a Coldhouse one.
Dave_Geologist [during the end-Permian] there was no Ice Age, despite presumably much the same continental configuration as in the Carboniferous-early-Permian Gondwana Glaciation.
That’s just show that the right continental configuration may be a necessary, but not sufficient condition. Most likely too much of CO2 and/or CH4 in the air that reduced the drop in Temp. shortly before P-T boundary and then reversed it into a massive spike in T shortly afterward. If I remember correctly – the main suspects for that were:
– geology – massive volcanic activity forming extensive Siberian Traps – which added CO2 and CH4 directly from the volcanic exhaust, and indirectly if it burned through the recently deposited fossil fuels (massive coal deposits from the first half of Carboniferous)
– biology – there was PNAS 2014 paper (Rothman et al.) about an archean Methanosarcina acquiring via horizontal gene transfer from another microbe a piece of DNA enabling it to break down marine organic matter to CH4 and CO2 – resulting in the massive spike of CH4 – leading to the climate change from hell (T up, ocean acidification up, drop in air O2 AND increased thermal stratification -> anoxic conditions in ocean) and the greatest mass extinction ever.
In this scenario, Siberian traps volcanism had a helper role – providing nickel needed by the methanogenic enzymes to function.
I haven’t followed this theory – Dave do you know whether it has been supported or falsified since?
I remember that paper Piotr. I was not convinced at the time, given that we know what CO2 does and the end-Permian was the largest LIP we know about. Also there were millions of years of very hot early Triassic, which is more consistent with CO2 than methane, which should give a short, sharp spike until it oxidised to CO2. Or if the methane flux was permanently high, it should have stayed permanently warm. Methane is also complicated by the fact that the sills associated with the LIP intruded into Gondwanan coal beds, which will have released CH4 and/or CO2, depending on how hot the coals got and how much oxygen was available. There’s also evidence of a double-whammy in that isotopic evidence indicates substantial subduction-related volcanism in South China just prior to the LIP, which will have had the added complication of volatiles emitted from the subducting material.
The plate-tectonic configuration was pretty similar (continent at the South Pole, ocean at the North Pole). Incidentally there’s an excellent recent, open-access (I think, but it’s also on ResearchGate) compilation by Chris Scotese, the doyen of this stuff: An Atlas of Phanerozoic Paleogeographic Maps: The Seas Come In and the Seas Go Out (doi 10.1146/annurev-earth-081320-064052).
Dave_Geologist, Thanks for the reference, fascinating.
Dave_Geologist There were millions of years of very hot early Triassic, which is more consistent with CO2 than methane, which should give a short, sharp spike until it oxidised to CO2. Or if the methane flux was permanently high, it should have stayed permanently warm.
Er…, there is a third scenario between these two extremes – the production of CH4 that is neither too short nor too permanent, but just right to explain the sharp increase in temperature during the PT boundary and continuing “over millions of years to the very hot early Triassic” – as seen in the reconstruction of Judd et al above. And the plausible reason for that is would take Methanosarcina a long time to work through the all the organic carbon that had accumulated there for 10s? 100s? of millions of years of Paleozoic because of the low-oxygen in the deeper ocean prevented decomposition of organic matter by aerobes, and the shortage of methanogenes and/or their Ni-starvation, who needed Ni for their enzymes and there was a Ni shortage because Ni associated with high-temp magma. Which finally was being supplied at “ the end-Permian [by] the largest LIP we know about“. which combined with the new branch of microbes acquiring ability to produce CH4 –
jumpstarted the organic matter decomposition there. But given the amount of the organic matter accumulated in the ocean – it would take many milllions of years to work through it – thus providing sustained flux of CH4 for millions of years, that may expalin the sharp increase in temp. starting just before the P-T boundary and continuing into millions of years of early Triassic, seen in Judd’s temp. graph.
In your alternative the many million long increased in T caused by the LIP – either via degassing of CO2 or the burning through the recently deposited coal deposits in the Siberian traps – would have require a massive increase in CO2 – NOT SUPPORTED by the CO2 reconstruction by Judd et al. – their fig 4 – where the T keeps increasing SHARPLY in the early Triassic, while Co2 stays flat or actually declines.
Therefore Judd’s reconstruction of T and Co2 IS NOT “ more consistent with CO2 than methane
and therefore is LESS consistent with the LIP Co2 as the main driver, and MORE consistent with methanogens as the main driver, with LIP most consequential role being that of a supplier of Ni to methanogens.
I had a look on Google Scholar for citations of the Methanosarcina paper.
About half were biological or biochemical, with no obvious geology link. All the geology or mass extinction ones were about volcanoes, apart from a self-cite by the lead author. If it hasn’t gained acceptance among geologists in a decade, it probably never will.
Dave_Geologist: If it hasn’t gained acceptance among geologists in a decade, it probably never will.
Haven’t they said it about that meteorologist Wegener’s crazy theory ? ;-)
Not quite Piotr.
For half a century geologists found Wegener’s observations compelling, but continental drift foundered on the lack of a geophysical explanation of how continents could move, effectively ploughing through the ocean floors (you could deduce from isostasy that the Moho had to be much shallower under the oceans). The alternative also had problems (whole continents sinking under the sea (where did the water come from to fill in after them?; implausibly long and narrow land bridges to avoid material-balance problems?).
Once it was realised that the continents were mere passengers on combined oceanic-continental plates, it was obvious. The final clincher resulted from observations using technologies developed during WWII.
BTW it’s a myth that it was accepted one death at a time. 95% or 99% of geologists switched during their careers. At a conference in 1973, an American attendee quipped that it flipped so fast there that one year you couldn’t get tenure if you accepted plate tectonics, the next year you couldn’t get tenure if you didn’t accept plate tectonics. Europe flipped 5-10 years earlier, and the Soviet Union never did, at least during Belousov’s lifetime.
The best book for a blow-by-blow account, with interviews with and chapters by many of the key participants, is Naomi Oreskes’ Plate Tectonics: An Insider’s History of the Modern Theory of the Earth.
The difference with CO2 vs. methane is that we know the physics of CO2, we know shedloads of it were emitted from volcanoes, and it didn’t just happen once so even if CH4 was a factor in the P-T (and there are potential sources other than methanogens, sources which we know were emitting), it wasn’t in the others and the biggest bang must have caused the biggest CO2-driven warming. We even know how quickly it happened: very, in the order of 100,000 years (although not quickly compared to post-industrial times, obviously). Volcanism continued for a time after the extinction event, and that has been implicated in the delayed recovery of biosystems.
Dave_Geologist: Not quite Piotr. For half a century geologists found Wegener’s observations compelling, but continental drift foundered on the lack of a geophysical explanation of how continents could move
I am not sure about your: “ For half a century geologists found Wegener’s observations compelling” – as you have said yourself that for many decades “ you couldn’t get tenure if you accepted plate tectonics”
And the attacks no Wegener were not limited to pointing that we didn’t know a plausible causative mechanism for the continental drift (after the geology at the time couldn’t come up with ANY alternative mechanism OF THEIR OWN that would have explained Wegener’s “compelling observations”), but were also shaped by the fact that Wegener was:
– German (not a particularly endearing trait in the AngloSaxon world after WWI)
– young (came up with his idea in his early 30’s),
and worse of all
– a … meteorologist who dared trot over the area of expertise of the respected geologists of the time.
As a University of Chicago geologist put it during the American Association of Petroleum Geologist special conference devoted to repudiation of Wegener’s idea in 1930:
“ If we are to believe Wegener’s hypothesis, we must forget everything which has been learned in the last 70 years and start all over again. ”
So my point was that “ having not gaining acceptance among geologists in a decade is not exactly a death blow to a validity of a theory… ;-)
P.S. Particularly, that unlike Wegener, the authors of the PT boundary paper offered and discussed a plausible mechanism and how it can fit with the observations. So your observation that:
D-G: “ About half of [the paper’s citations] were biological or biochemical, with no obvious geology link”
… might not be as damning after all ;-)
Dave G. “ Piotr, you still have to come back to the enormous release of volcanic CO2 (and other sources like baked coal seams) in a very short time
could you point to this enormous release of volcanic CO2 in the discussed here paper (see their Fig.4) ?
During your “millions of years of very hot early Triassic” – Co2 is flat, despite T sharply spiking up.
Dave G.: The CO2 can’t not warm the planet.
The increase in Co2 can’t. But according to the discussed here paper – during the PT boundary and in the following “.millions of years of very hot early Triassic“CO2 was flat.
Dave G. – Dismissing the LIP founders on the same rock as the modern ABC crowd who leap on cosmic rays, solar cycles, or schoolboy errors confusing the heliocentre with the baryocentre.
Hitting below the belt, Dave? Unlike people who confuse the heliocentre with the baryocentre. – the PNAS paper:
– provided plausible mechanism (horizontal gene transfer),
– dated it molecularly to around the PT boundary
– high organic carbon pool in the and anoxic conditions in the deep ocean at the time are exactly the environment where methanogens can thrive,
– high-temp from the large volcanic activity is a good source of Nickel that otherwise would have been a limiting metal for the methanogenic enzymes
– as for your: “methane, should give a short, sharp spike [in T] until it oxidised to CO2. Or if the methane flux was permanently high, it should have stayed permanently warm.”
I have already given you a third scenario between your two extremes, which could explain the rise in temp. on intermediate time scale (“millions of years of early Triassic”):
(P: “the production of CH4 that is neither too short [you can’t quickly go through the large pool of organic carbon accumulated during the Paleozoic], nor permanent [since at some point that pool would have been exhausted]”)
– and the discussed here paper is inconsistent with increased CO2, but consistent with increased of CO2
So you can’t wave off the above arguments by putting them on the same level of credibility as “people who confuse the heliocentre with the baryocentre“.
Piotr, you still have to come back to the enormous release of volcanic CO2 (and other sources like baked coal seams) in a very short time, and the physics of CO2. Dismissing the LIP founders on the same rock as the modern ABC crowd who leap on cosmic rays, solar cycles, or schoolboy errors confusing the heliocentre with the baryocentre.
The CO2 can’t not warm the planet. Then as now. Of course other things can contribute, including oceanic methanogens, just as cows and deforestation contribute today.
The comment about the cites wasn’t meant to be damning: they’ve obviously come up with some interesting and novel biology and biochemistry. I agree it’s very interesting, although the usual caveat against being attracted to new, shiny things applies. And the bio references are an endorsement that it was a real advance, not just an ephemeral shiny thing.
The bits that geologists accepted were Wegener’s fossil and geology/mountain belt correlations, which showed that absent large land animals that could fly or could swim 3000 miles, Africa had once been contiguous with North America. The very bits where prejudice against his profession ought to have had most impact but didn’t. Interestingly, despite his supposed dismissal, one year after that throwaway remark at an oil industry conference, one of the giants of academic geology at the time, Arthur Holmes, proposed mantle convection as the mechanism.
As with evolution’s God of the Gaps fallacy, the more we learn the more the gaps are closed and the less room there is to hide for something that replaces rather than adds to current knowledge. We won’t unlearn the physics of CO2, any more than we’ll unlearn Glossopteris fossils or seafloor magnetic stripes.
Sheesh, i accidentally sent unfinished draft (and to make it better – attached it to the wrong post). So here it goes again:
Dave G. “ Piotr, you still have to come back to the enormous release of volcanic CO2 (and other sources like baked coal seams) in a very short time
Could you point to this enormous release of volcanic CO2 in the discussed here paper? I ask because in their Fig.4 during your “millions of years of very hot early Triassic” – despite the spike in T, Co2 is flat.
Dave G.: The CO2 can’t not warm the planet.
The increase in Co2 can’t. But according to the discussed here paper – during the PT boundary and in the following “.millions of years of very hot early Triassic“CO2 was mostly flat.
Dave G. Dismissing the LIP founders on the same rock as the modern ABC crowd who leap on cosmic rays, solar cycles, or schoolboy errors confusing the heliocentre with the baryocentre.
Hitting below the belt, Dave? Unlike people who confuse the heliocentre with the baryocentre, the PNAS paper:
– provided plausible mechanism (horizontal gene transfer),
– dated it molecularly to around the PT boundary
– high organic carbon pool in the and anoxic conditions in the deep ocean at the time are exactly the environment where methanogens could thrive,
– high-temp magma from the large volcanic activity is a good source of Nickel that otherwise would have been a limiting metal for the methanogenic enzymes
– as for your: “ methane, should give a short, sharp spike [in T] until it oxidised to CO2. Or if the methane flux was permanently high, it should have stayed permanently warm. ” – I have already given you a third scenario, between your two extremes, which could explain the rise in T on the intermediate time scale (“millions of years of early Triassic”):
(P: “the production of CH4 that is neither too short [you can’t quickly go through the large pool of organic carbon accumulated during the Paleozoic], nor permanent [since at some point that pool would have been exhausted]”)
– and the discussed here paper is inconsistent with increased CO2, but consistent with increased of CH4
So you can’t wave off the above arguments by putting them on the same level of credibility as “people who confuse the heliocentre with the baryocentre“.
This is fantastic. I recently completed a tree-ring study which shows the same thing and had it published here:
https://www.hyzercreek.com/Manns_Law.html
Thank you!
Congratulations!
Susan Anderson 15 Oct “Congratulations!”
Definitely! Morgan Wright is a master in spoofing climate change deniers – ridicules their knowledge, the wandering of their brains on tangents, and even their writing style. Enjoy:
=== Title: Tree Rings: A Proxy Of Global Paleoclimate. Evidence to support Mann’s Law of Dentroglobalpaleoclimatology ====
Morgan Wright OD et al
==
Abstract: This study gives further evidence of the robustitude and rigorosity of Mann’s Law.
We used a single Tsuga canadaensis specimen in upstate New York. Slow growth between 1970 and 1983 was due to a cold period in Earth’s history, known as the Global Cooling Scare. During Climategate, scientists used the Nature trick to hide the decline, but the decline was real, as we show here.
Slow growth between 1937 and 1955 was also due to global cooling during the cold war. In 1953, 1954, and 1955, the rings are so close they can barely be seen. This extremely cold period was because it was a VERY cold war.
======
;-)
Morgan, do anti-vaxers now, pleeease!
Morgan Wright, delightful! Thanks for that :-)
.
Piotr & Susan, Ha! Who says science is not fun?!? First time I’ve laughed today.
in Re to Morgan Wright, 13 Oct 2024 at 1:32 AM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825393
Dear Morgan,
I opened the link
https://www.hyzercreek.com/Manns_Law.html
that you have provided. Unfortunately, I found an abstract only, without any clue towards the fulltext of your article. The picture thereon looks impressively.
Nevertheless, without further support by data convincingly showing that the changing density of the depicted tree rings indeed correlates with global temperature fluctuations, rather than with mean local temperature, cumulative sunshine time and/or cumulative precipitation during individual growing seasons in Hyzer Creek, the picture alone might be quite misleading.
Could you help?
Thank you in advance and best regards
Tomáš
Tomas Kalisz: “ Dear Morgan,I opened the link that you have provided. Unfortunately, I found an abstract only, without any clue towards the fulltext of your article. The picture thereon looks impressively.[…] Could you help? Thank you in advance and best regards”
Facepalm … You read the “abstract” containing such gems as :
“ Slow growth between 1970 and 1983 was due to a cold period in Earth’s history, known as the Global Cooling Scare. During Climategate, scientists used the Nature trick to hide the decline, but the decline was real, as we show here. Slow growth between 1937 and 1955 was also due to global cooling during the cold war. In 1953, 1954, and 1955, the rings are so close they can barely be seen. This extremely cold period was because it was a VERY cold war. ”
and you think to yourself – “Gee, that’s impressive scientific writing. I wish I could read the whole thing!” ???
Have you learned NOTHING from your 1.5 year stay on this group, nor from reading the real scientific papers?
in Re to Piotr, 18 Oct 2024 at 7:32 PM,
https://www.realclimate.org/index.php/archives/2024/09/phantastic-job/#comment-825557
Hallo Piotr,
Thank you for your explanation.
I have not grasped that it is a joke (although “the very cold war” might have been in fact a very good hint :-)).
I am a little bit sorry that there is (likely) no accompanying data at all. I admit that the picture sparked my curiosity and I hoped that I could see how well the tree rings pattern in a specific specimen correlates with the weather record in given location.
Greetings
Tomáš
– Tomas Kalisz: “ Dear Morgan, Unfortunately, I found an abstract only, The picture thereon looks impressively.[…] Could you help? Thank you in advance and best regards”
– Piotr: “Facepalm … You read the “abstract” containing such gems […]and you think to yourself
– “Gee, that’s impressive scientific writing. I wish I could read the whole thing!” ???
Have you learned NOTHING from your 1.5 year stay on this group, nor from reading the real scientific papers?
– Tomas Kalisz : “Thank you for your explanation. I have not grasped that it is a joke although “the very cold war” might have been in fact a very good hint :-)
_That_ was your hint – and NOT: “ a cold period in Earth’s history, known as the Global Cooling Scare. During Climategate, scientists used the Nature trick to hide the decline, but the decline was real, as we show here” ???
Piotr, it may not be mentioned in that paper but it is mentioned in hundreds of other papers spanning decades, by people who went out and measured the things you need to measure. Not just to estimate CO2 content, but to detect volcanic action (Hg, for example, and of course a large Igneous Province you can’t miss, which modern dating has shown was very-short-lived in geological terms and which therefore can’t not have pumped huge quantities of CO2 into the atmosphere), and cooked organic matter (inertinite).
I don’t deny (the possibility that) methanogens made a contribution. But I can’t ignore the mountain of evidence that we’d have had a hothouse world with or without methanogens (and there are also loads of papers explaining why it stayed warm through the early Triassic, in part due to, yes, volcanoes, again, perhaps with added methanogens). Maybe they were the icing on the cake and that’s why it was the biggie, but the cake would remain, with or without icing.
Dave G.: “ and of course a large Igneous Province you can’t miss, which modern dating has shown was very-short-lived in geological terms and which therefore can’t not have pumped huge quantities of CO2 into the atmosphere)
You have lost me – you say that I “ can’t miss of course a large Igneous Province” BECAUSE it was very-short-lived in geological terms and which therefore can’t not have pumped huge quantities of CO2 into the atmosphere? Wouldn’t make it missing it …. more likely ?
And weren’t you just contesting the role methane by saying:
“ There were millions of years of very hot early Triassic, which is more consistent with CO2 than methane, and now … you are telling that large Igneous Province “ can’t not have pumped huge quantities of CO2 into the atmosphere“.
You see the problem with holding these two views at the same time, right?
Dave: “ that we’d have had a hothouse world with or without methanogens”
The fact that we can have a hothouse without methanogens, does not prove that methanogens can’t cause a hothouse, no more than the fact that you can kill a man without a gun does not mean that you can’t kill a man with a gun.
Dave G.” I don’t deny (the possibility that) methanogens made a contribution. But I can’t ignore
So do I: I don’t deny (the possibility that) volcanism made a contribution. Through the direct emissions and burning through the coal in Siberian traps, providing So2 for ocean acidification and for reaction with methanogenic CH4 producing toxic H2S (CH4 + SO2 = CO2 + H2O + H2S ) that may have helped to kill off terrestrial species, and with high T magma a good source of Nickel, necessary for methanogenic enzymes.
But I can’t ignore … your own words that “ large Igneous Province was very-short-lived in geological terms” and therefore should have caused a spike in heating following by rapid cooling, while as you said yourself – the high temps continued into millions of years of very hot early Triassic,.
Which, contrary to your conclusion, is more consistent with the biological production of CH4 and CO2 than with the “very-short-lived” burst of CO2 from volcanoes.
A good recent summary of the geochemical and dating evidence is available on ResearchGate, here: https://www.researchgate.net/profile/Jun-Chen-154/publication/333450241_Establishing_the_link_between_Permian_volcanism_and_biodiversity_changes_Insights_from_geochemical_proxies/links/611916bb1ca20f6f8623120d/Establishing-the-link-between-Permian-volcanism-and-biodiversity-changes-Insights-from-geochemical-proxies.pdf
There’s another good paper on ResearchGate, Piotr, which links geochemistry to the extinction steps: https://www.researchgate.net/profile/Paul-Wignall/publication/275256794_Progressive_environmental_deterioration_in_northwestern_Pangea_leading_to_the_latest_Permian_extinction/links/554fc9f508ae93634ec878da/Progressive-environmental-deterioration-in-northwestern-Pangea-leading-to-the-latest-Permian-extinction.pdf
Shelly organisms went first, linked to a rise in the CCD (which has to be CO2, and while you could argue that it came from methanotrophs eating methanogen products, quite plausible given the dispersed, microscopic generation sites, in that case the CH4 never made it to the atmosphere). Then (most) burrowers and siliceous sponges, coinciding with a spike in toxic heavy metals tied to volcanism, and finally marine anoxia got the rest.
Dave G. “Shelly organisms went first, linked to a rise in the CCD (which has to be CO2, and while you could argue that it came from methanotrophs eating methanogen products”
Not only. Methane fermentation itself produces equal amount of CH4 and CO2.:
2CH2O -> CH4 + CO2
Add to this oxidation in the surface water of SOME of CH4 to CO2 – and you may have enough acidity to raise CCD, (particularly if supplemented with acid rain from SO2 volcanic emissions and flow of acidity
in rivers from oxidized sulfides in rocks). while still leaving ENOUGH CH4 getting into the air to raise air temp – And you would not need that MUCH – at current concentrations and 20-yr scale GWPotential of 1kg of CH4 is about 8ox that of CO2.
Thus shelly organisms being the first to go – does not prove that the source of acidification must have been volcanic Co2.
And finally Piotr, very recent work has shown that terrestrial ecosystem collapse predated the marine extinctions, indicating an atmosphere-to-ocean cause-and-effect, not ocean-to-atmosphere: https://www.researchgate.net/profile/Lu-Jing-6/publication/368552995_End-Permian_terrestrial_ecosystem_collapse_in_North_China_Evidence_from_palynology_and_geochemistry/links/63f1d2ba31cb6a6d1d145fef/End-Permian-terrestrial-ecosystem-collapse-in-North-China-Evidence-from-palynology-and-geochemistry.pdf
Dave_Geologist: Very recent work has shown that terrestrial ecosystem collapse predated the marine extinctions, indicating an atmosphere-to-ocean cause-and-effect, not ocean-to-atmosphere
I don’t think this proves what you think it does. It would ONLY do so, if CH4 produced in the ocean was immediately toxic to marine fauna, so they would die BEFORE CH4 degassed into the atmosphere could have caused, via GW, the death of terrestrial fauna.
But I have no reason to think it is so – in the realistic concentration CH4 has rather limited direct toxicity…
– “ A report by Pennington and Fuerst (1971) supported the biologic inertness of methane.”
– ” methane has little effect when oxygen is readily available. “.
– cows do not seem to kick the bucket because of all the exposure to methane produced by microbes in their stomachs, produced in large enough amounts to warrant this advisory:
“ If you are working in an area where cattle are present, it’s generally advisable to exercise caution with flame equipment and avoid using it in close proximity to the animals, especially after they have eaten.“)….
Also, in the ocean – areas around methane seeps are often places with high concentration of animals.
So my sequence of events:
methanogens produce CH4 ,which degasses (without mass killing of marine org.) into the atmosphere. There, being a MUCH more effective GHG than CO2 – causes massive GW -> to which the land having smaller thermal inertia is more vulnerable than the ocean -> land extinctions first.
Only later when the atm heat warms the surface ocean enough – extinctions in the ocean happen -> perhaps directly through overheating (the way today’s coral reefs are destroyed primarily by the heat waves), but MORE universally – indirectly via hypoxia/anoxia” as hotter air (due to CH4 emissions)
warms the surface water:
– the warmer the surface water the less O2 from air dissolves in water
– the warmer water -> the stronger/shallower the vertical stratification -> less vertical mixing -> smaller supply of oxygen from surface to subsurface layers PLUS lower supply of algal nutrients, N and P, from below toward the surface -> lower algal photosynthesis -> lower production of oxygen in the seawater
At the same time of the reduced supply and production of O2 in water – the warmer water means also higher demand (since metabolism gets faster in warmer waters)
Anoxia or even hypoxia – would kill most of the marine animals much more effectively than the increasing seawater temp. on their own, or direct CH4 toxicity. The latter, incidentally, might have … increased sharply with lowering O2: “the toxic effect of methane is much greater than that of nitrogen when available oxygen is low, but methane has little effect when oxygen is readily available. “.
Finally – the death of animals and aerobic bacteria would mean more food for organisms that don’t need oxygen. Like the methanogens …
So in my scenario, one would EXPECT the extinction on land to precede the extinction in oceans.
Thus your paper is consistent with that and consistent with my: ocean-to-atmosphere-to ocean cause and effect.