Climate Sensitivity

Global Warming Less Likely to Be Catastrophic, Says New Nature Study

That would mean more time to address whatever problems man-made climate change may cause


Alex Parfenov/Dreamstime

Probably the most vexing problem in climate change science is determining how hot the planet would become if the amount of carbon dioxide in the atmosphere doubles from it pre-industrial level of 280 parts per million. Known as equilibrium climate sensitivity (ECS), the Intergovernment Panel on Climate Change's Fifth Assessment Report put the likely range of ECS as being between 1.5 and 4.5 degrees Celsius.

The current level of carbon dioxide in the atmosphere is around 403 parts per million. Carbon dioxide in the atmosphere is now increasing annually at about 3 parts per million. If that rate of increase keeps up, the amount of carbon dioxide in the atmosphere will double by the end of the century.

As bad as an increase of 4.5 degrees Celsius would be—and it would be really bad considering that the difference between now and an ice age is 4 to 7 degrees Celsius—a big concern has been that researchers have not been able to rule out that future temperatures might exceed the 4.5 degrees Celsius. In a new study published in Nature, University fo Exeter mathematician Peter Cox and his colleagues claim that they have constrained ECS to a lower range of values. From the abstract:

Here we present a new emergent constraint on ECS that yields a central estimate of 2.8 degrees Celsius with 66 per cent confidence limits (equivalent to the IPCC 'likely' range) of 2.2–3.4 degrees Celsius. … [Their procedure] enables tighter constraints to be placed on ECS, reducing the probability of ECS being less than 1.5 degrees Celsius to less than 3 per cent, and the probability of ECS exceeding 4.5 degrees Celsius to less than 1 per cent.

To greatly simplify, Cox and his colleagues compared how climate models handled year-to-year variations in surface temperatures with the historical temperature record. In doing so, they found that the climate models that yielded higher ECS values failed to replicate what has been happening to actual temperature trends.

In his perspetive article in Nature, Leeds University climatologist Piers Forster explains, "Their analysis revealed that only climate models that produce relatively small values of ECS match the variability seen in the historical temperature record." Forster adds, "If the upper limit of ECS can truly be constrained to a lower value than is currently expected, then the risk of very high surface-temperature changes occurring in the future will decrease. This, in turn, would improve the chances of keeping the temperature increase well below 2?°C above pre-industrial levels, the target of the Paris Agreement under the United Nations Framework Convention on Climate Change."

That would be good news indeed.

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  1. Well, this news is certainly going to disappoint some in the climate change community.

    1. No, they’ll just claim Nature has been bought out by Big Oil and is now acting as their mouthpiece to perpetuate the lie that Mother Gaia is not actually angry and prepared to kill us all very soon.

      1. Mommy nature’s deadly and a real bitch.
        She needs to be taken apart, experimented on, then exploited for fun and profit.

    2. Why the hell would it do that? Please explain.

      Also explain why suddenly science is trustworthy when the report is more optimistic.

      1. Funding would come under threat.
        But really, this is just past experience. Every time good news comes out, the cultists react negatively, and it’s obvious why. Fewer people panicking = less funding for studies. Follow the money.

        1. That would be outrageous if it were remotely true.

          1. Out of all the gloom and doom prophets I remember, from Rachel Carson on, I never recall any of them saying, “Oh glorious day; things aren’t as bad as I predicted.” Even after things manifestly weren’t as bad as they predicted.

            1. Ehrlich is still peddling the ‘end times ’cause TOO MANY PEOPLE!’. And still getting paid for it; a fool and his money…

            2. As this article unclearly states, things are not all peaches and cream. Just less worse than absolutely catastrophic. Perhaps moderately catastrophic.

              Of course if you went on denying every scientific report on this subject until now, you as a grown adult should probably ask why you’re being such a ridiculously selective hypocrite.

              1. Tony! Stop for a second. You are too close to the subject if you can’t understand what they’re saying. No one is arguing that something shouldn’t be done. They are simply saying that the average person, without claiming the validity of the reaction, will be to say then there is no reason to panic and as such will suggest we spend less to fund research or resolution. That’s it. Surely you can agree that in general humans don’t do anything as a group, especially when that has any appreciable negative affect on the group, until Armageddon is upon them. Isn’t that what you are usually so demonstrative about?

                1. I am arguing nothing should be done.
                  1. If you are a Christian, God is in control and there is no need to worry.
                  2. If you are an evolutionist, extinction of a species, including the humans, is a part of evolution, and should not be interfered with.
                  3. If you are capable of logic and reason, all proposals to ‘fix’ global warming are worse than the possible, projected, maybe, could be, worst case situation.

              2. IF this report is correct, then all the other reports are incorrect. But we already knew that because temperature has been basically flat for the past 30 years despite a continued increase in CO2 emissions.

                Bottom line is that the models of the experts don’t accurately model the actual temperatures we’ve seen over the past 30 years. So the models are not correct. Yet the experts continue to want to tell us all how to live based on their models.

                Global warming (I mean, climate change) is basically religion to many. The climate scientists have a good gig by getting plenty of gov’t funding and being invited to fancy climate conferences by wealthy greens.

              3. Tony has it right. The article actually says the expected result is more certain than before. But extreme worst AND best case scenarios are less likely. This is not good news for anyone that wants to continue “business as usual”. CO2 is a greenhouse gas, temperatures go up when we release CO2 into the atmosphere, and we are more certain that the response to CO2 will have rather severe consequences for us. Interesting the headline only deals with the worst case scenario not coming to pass and ignores the equal conclusion that the “best case” scenarios also really are not realistic.
                But I am at least glad to see that someone at Reason thinks that climate science has a solid understanding of basic physics and chemistry which are the root of the reason climate scientists ask questions about the impacts of our CO2 emissions.

      2. Only pessimistic science is trustworthy!

      3. Tony, what generates more fervor for sweeping policies to combat climate change?

        A: “We’re at a crucial tipping point beyond which catastrophe lies!”

        B: “Well, things might get pretty bad. Or they might not. We’re not sure.”

        1. Scientists shouldn’t have to have PR teams, but apparently with Republicans and their leg-humpers in the world, it’s necessary.

          1. “Scientists shouldn’t have to have PR teams, but apparently with Republicans and their leg-humpers in the world, it’s necessary.”

            Turd-sucking Democrats believe this.

          2. You don’t actually know any scientists.

            All funding in all fields is dependent upon a sense of “impact factor” which translates into what scientists currently think is “sexy”. Ewwww.

          3. Re: Tony,

            Scientists shouldn’t have to have PR teams

            They will need them now. They lied to us, repeatedly.

            1. This article in Nature actually says their expected results are MORE likely. That the scientists understood it BETTER than they thought. The best case AND th worst case responses are less likely! The expected impact is more likely to happen – not less likely. Old Mexican’s Speedos needs to learn to read a bit more critically.

          4. They don’t need PR teams

            They need accurate predictions

            All predictions have turned out to grossly overestimate temperature increase


            1. Including this one?

              1. So only THIS per reviewed work is wrong or all others are by your Susanna that you so loving uphold as “consensus”.

              2. Hard to say. But what is undeniably true is that the models that the paper criticize do not accurately predict the actual temperatures that we’ve seen globally over the past 30 years. That is simply a fact, not conjecture.

                Global temperatures have barely moved over 30 years despite a continued increase in CO2 emissions. The models predicted an increase in global temps. So if you want to tell everyone how to live based on their climate models, get some models that actually accurately predict the temperatures we’ve already recorded. The models should be accurate going forward and backward. They are not.

      4. Because love is love and science is real.

        1. Someone watched Interstellar recently.

          1. No, I took my dog for a walk and read the yard signs.

      5. The report isn’t science; it’s speculation. Any report based on climate models is speculation, because that’s what the models are. Science requires, at a minimum, a falsifiable hypothesis, a repeatable experiment, and a diligent search for alternate explanations for the observations. None of that is part of the models.

        1. According to your criteria, astronomy, geology, and paleontology are not sciences. Not all science requires experiments. If your models correctly predict the future, or consistently explain the past, that is good science.

          1. Please cite one climate change/global warming/whatever model over 5 years old that has is accurate.
            Thank you.

            1. That… doesn’t relate to what he said.

              1. That… doesn’t relate to what he said.

                Of course it does. CMB said if a model predicts the future it is good science. On that front climate science has been shown to be very weak in its ability to predict the future, now that the future from predictions made 10 to 20 years ago is here.

                1. He was responding to someone claiming that it’s not science at all, not that it isn’t good science. Of course climate science is a legitimate area of scientific inquiry. The question is whether it has been successful in modeling the climate, not whether it’s actual science or not.

        2. Art Gecko’s idea that scientists are supposed to have created a second earth with a “control” atmosphere where man did not increase CO2 concentrations from 285 ppm pre-industrial to over 400 ppm current is rather preposterous.
          There are many “control” experiments that have been done on the basic physics and chemistry behind climate change. That is why we use atomic adsorption spectroscopy to figure out what chemicals are present and at what concentration. The basic pieces of climate change science are simply not in question.
          Models are used in many fields to help us predict the future and also to help us understand where we need to focus more attention.
          All models are wrong – but some are useful. Currently both weather and climate models are very useful – but certainly not 100% accurate.

      6. Oh Tony, we could try to explain any number of things to you. But in the end, your stupidity, poor education, and dogmatic adherence to your Marxism make it an exercise in futility.

      7. “they” would do it. “them” duh.

    3. Fake news from climate deniers. See how easy that was?

    4. Im making over $7k a month working part time. I kept hearing other people tell me how much money they can make online so I decided to look into it. Well, it was all true and has totally changed my life.
      This is what I do =====???

  2. “If that rate of increase keeps up….”

    You know who else wanted to keep things under control?

    1. Sheriff Buford T. Justice?

  3. Gosh golly pendejos, Ronny Baby, do ya think?

    1. Ronny Baby, are you really that stupid, or just dense?

  4. Ron, you’re doing this wrong. You are supposed to be wringing your hands saying “I can’t believe these deniers got their lies published!”

    But in all seriousness, It’s truly impossible to have reasonable discussions with most people on the subjects of “Climate Change” and “Anthropogenic Climate Change”. Those who bought into the fad can’t let go. Others truly have accepted the religion, so anything contrary to their belief is heresy. Those who haven’t tend to be a little ridiculous in their dismissals of some of the less contentious stuff.

    1. 1. Scientists initially estimate climate will warm between 1.5 and 4.5 degrees Celsius
      2. Further research tightens that estimate to 2.2 – 3.4 degrees Celsius
      3. This somehow proves to the H&R Know Nothings that the real answer was zero all along because Jesus or something

      1. You realize it’s Bailey’s own headline that says “less likely to be catastrophic”, right? Can you tell me who said it was zero? Or do you just believe that because of your programming and you’re not actually informed on the nuances of the debate?

        1. Kivlor’s “Those who bought into the fad can’t let go” for example.

          See, things aren’t actually getting warmer. It’s just a fad!

          1. I think you prove my point Stormy. There’s not rational discussion to be had. You miss the point that a scientific fad can have a lot of truth to it. When things like this become a fad they get distorted, as does how they are funded. AGW has left the realm of science when discussed in regular discourse, and has truly become a form of pagan Gaia Worship and overrun with people screaming “Mother Gaia is angry and the Apocalypse is nigh! She will kill us all for our sins!”

            The right questions to ask are: How much is the Climate changing? How much of that is due to human activity? How much is due to other natural phenomena? Is this change dangerous? How dangerous? Is intervention necessary? How can we do so without setting humanity back to the dark ages?

            1. And Kivlor retreats to the Motte.

              1. Stormy, you ARE the reason catastrophists get laughed at here.

            2. Stormy, I’ve not retreated to the motte because nothing I said was controversial and no retreat was necessary. I’ve defended exactly what I said while you’re off tilting at windmills.

        2. The warming has to be catostrophic, because warming of a little bit might actually be good. Sure would improve crop yields in many places and increase the growing seasons in many others.

          Just curious, what is the “correct temperature?” If the present global temperature is X, who knows what the global temperature is supposed to be? If the “proper” global temperature is X+Y.then global warming is a good thing, isn’t it?

          For the greens to make this work, the “proper temperature” has to be a lower temperature than X, global warming has to be caused by man (otherwise you can’t fix it), and has to be catostrophic. Why? Because the goal is to scare you into giving them greater authority to manage your lifestyle and the global economy.

          1. In Stormy’s defense, he’s an avowed leftist so that scenario doesn’t sound bad to him.

            Tony too for that matter.

      2. You prove my point Stormy. Jesus had nothing to do with anything I said. Nothing I said denies that the overall temperature of the planet may in fact be warming. Instead, you latch onto some imagined argument I’m not making.

        I specifically criticized those who completely deny points RE: Climate Change that are not contentious. Some examples to extrapolate: Climates have always and likely will continue to change forever. Humans certainly can alter the climate if the Chinese can build a lake that measures alters the earth’s rotation and tilt.

        It becomes difficult to take the Climate Change crowd very seriously however when they behave like the cultists that many of them are. They are no different than the crazy Christian on the street corner screaming that God’s Judgement is nigh for He has grown tired of our sins.

        1. ***measurably alters***

      3. Hey Stormy, since you are here to enlighten all us unbelievers.

        Can you point to 1 prediction that has come true? Come on share with the class.

        Is it no snow by 2010?
        No ice at the north pole by 2012?
        Hurricanes will be more frequent and stronger?

        I mean I promise not to mention the falsified data, and the wrong understanding of the 99% of scientists agree than..or that the church of global warming gives out indulgences like the catholic church in the 1800. You have sinned! Plant a tree – signed Prohacle Gore

          1. Seven climate change predictions that have come true.

            1. Temperatures will rise in response to emissions of greenhouse gases…
            2. The average rise in temperature

            Post hoc ergo propter hoc.

            5. The oceans will rise

            And Florida used to be under water…

            It goes downhill from there, including the

            1. 1. Temperatures will rise in response to emissions of greenhouse gases…

              Global temp is flat over the past 20 years despite increase in CO2 emissions.

              That’s why the climate scientists (Mann and Co.) were talking about ways to “hide the decline…”

              1. Tommyguns2… Wrong.

      4. Piers in his “News and Views” piece does not mention the dozens of papers,
        some in Nature, that have predicted a median TCS or ECS or closer to 1 to 1.5 C.

        Hopefully the Cox paper does actually mention them.

  5. Well, that’s settled.

  6. I keep waiting for the government to solve global warming.

    And I keep waiting and waiting and waiting…

    1. I keep waiting for warmer weather. I hate winter. But it still keeps happening.

    2. How can they with such little funding and all the opposition from incest bred deniers???

  7. What was the estimated temperature during Eocene Age compared to today? That’s when the atmospheric CO2 was comparable to the projections we make now – and when much of the fossil fuel carbon we are burning today was still plants/etc – and it was still the same old sun

  8. Assume that the end is night.

    That still doesn’t justify any climate change political policy I have ever seen. None of it has any measurable impact.

    1. That’s about where I’m at. I’m no expert, so I’ll assume that the apparent prevailing view on climate change is more or less true (i.e. the view that humans are contributing to warming climate and that it may be really bad but probably won’t be). But trying to engineer human society to “fix” the problem won’t work and will do far more harm than good.

  9. Whatever the change in global temperatures might be, what are we supposed to do about it? Do humans have the ability/capacity to change things? Or should we just execute some Republicans and call it good?

    1. We go back to cooking on open fires, hunter-gathering, that kind of thing. While the people who designed the system sit in air conditioning eating caviar and fly to exotic places to talk about how they saved the planet.

      1. What do you mean “we”? The herd must be culled to down around 500,000 for humans to sustainably cohabit with the rest of the flora and the fauna as graze animals and that number sure as hell ain’t gonna include shitlords such as you and me. Only Marxist eco-feminist vegan atheists who self-identify as variably-gendered need apply.

    2. Remove all tax burdens for non-fossil fuel energy research. Privatize nuclear power generation. And so on.

      1. what tax burdens, as far as I can tell they get subsidies?

    3. As a libertarian, it is our charge to do something. Murray Rothbard. 1973. For a New Liberty; The Libertarian Manifesto: “And what of the increased costs that would have to be borne by the consumer? And what of our present polluting technology?
      The argument that such an injunctive prohibition against pollution would add to the costs of industrial production is as reprehensible as the pre-Civil War argument that the abolition of slavery would add to the costs of growing cotton, and that therefore abolition, however morally correct, was “impractical.” For this means that the polluters are able to impose all of the high costs of pollution upon those whose lungs and property rights they have been allowed to invade with impunity.”

  10. Probably the most vexing problem in climate change science is determining how hot the planet would become if the amount of carbon dioxide in the atmosphere doubles from it pre-industrial level of 280 parts per million.

    How about, as a start, filling a greenhouse with various gas mixtures and measuring what happens?

    1. Been done. In fact, Petr Beckmann reported that a greenhouse built with salt panels (transparent to reradiated infra-red) got just as hot as a glass greenhouse–or a car with rolled-up windows. But the kicker is that Tony over at gives away python scripts for downloading and graphing the thermometer readings. Anyone can show that temperatures are falling and have been for a century. Your AC breaks because of the fake freon freakout of 1987, that banned low-pressure freon to save the penguins around Mount Erebus.

      1. Wut.

    2. The problem with this is that much of the debate between skeptics and the other is on the runaway warming effect, in which CO2 increases the temperature, this induces other effects that release more CO2, and you get a feedback effect. Skeptics don’t believe the feedback is as dramatic as the current models assume. There’s no debate that CO2 causes warming, at least in our current situation. The question is the magnitude of the warming and if the current warming is due mainly to CO2 or a variety of factors.

      You can’t measure this in pretty much any environment for a reasonable amount of money. Perhaps if they used all of the climate money on one project, but that’s not how research works.

      1. CO2 also feeds the plants.
        I will take warm and green over cold and brown.

        1. And when plants feed on CO2, they sequester that CO2. The more CO2 available the faster plants sequester it.

          I agree with warm and green, though. An ice age shivers my timbers.

        2. It also melts continental glaciers and warms ocean waters – both raising sea levels and taking peoples property that live on/near coast lines. So you think we should be able to emit with no consequence or cost and not be responsible for the consequences of our actions. Not very libertarian.

  11. Just tell me what year will be the tipping point so I can put it on my calendar.

    1. One of the fun arguments in policy debate was when somebody would claim your plan would contribute to global warming. We’d just read sources that gave the tipping point as years ago. Usually it got dropped, because it’s a tedious and not fun debate.

  12. “That would be good news indeed.”

    Not to hucksters and shysters looking to score a buck or two off this cottage industry built on faulty premises and manipulation.

  13. That report is literally Hitler

    1. And Russian bots!

    2. Worse, it’s Super Hitler. Like Hitler, but a foot taller and riding a flying motorcycle, covered in iron swastikas.

  14. […] researchers have not been able to rule out that future temperatures might exceed the 4.5 degrees Celsius

    Of course they can’t. That’s where they draw their future income, in the form of grants.

    “How Global Warming Affects The Mating Call Of The Colorado Brown Toad”, and for that, I got a $250,000 grant!

    1. I hope that is a fake study you just made up. I could try to Google it except.

      1. It might be real and I can’t handle that fact.
      2. It’s 4am on Saturday and I reading this when I first woke up. WTF happened to my youth.
      3. Copy and paste on iPhone is too tedious for sentences.

  15. “That would be good news indeed.”

    Bad news for those who want to whip up hysteria to justify bigger government.

    They don’t care about the temperature. They care about Power.

  16. “[…] This, in turn, would improve the chances of keeping the temperature increase well below 2??C above pre-industrial levels, the target of the Paris Agreement under the United Nations Framework Convention on Climate Change.”

    Nope. No. I don’t believe it! They’re lying. We were promised socialism and the fall of Capitalism but how is this going to help us achieve it?

    Deniers!!!!! All of you!!!! DENIERS!!!!

    [Is then ddessed with a very long-sleeved jacket and driven to a nearby sanatorium for ‘rest and relaxation’)]

    1. “sanatorium”??

      Is that what they’re calling the nut houses these days?

      1. Hipsters are.

      2. ‘Nut houses’ are what I call my boxer-briefs.

      3. *it’s santorium, Rick is there and much happier. Lobotomized, but happier.

  17. Graphs of NOAA temperature measurements show a downward trend for the century, and an even sharper one since the 1940s. This is clear and evident to all who bother to look at the data. Government scientist-impersonators hide those graphs, alter the data so that the past is cooler and the present hotter, and show only the altered stuff. Their current altered output is not even consistent with their earlier lies! I’d wager that even Ronald Bailey could recognize a downward-sloping trendline if he ever saw one. The publishers of Nature? Those liars have more in common with the tailors in a Hans Christian Anderson story than with anyone qualified to join the over 31000 scientists who have signed the Petition Project. An honest scientific publication would show the raw and altered data side-by-side and NOT start shrieking about global cooling again like they did in the seventies.

  18. NSA deleted surveillance data it pledged to preserve

    To make matters worse, backup tapes that might have mitigated the failure were erased in 2009, 2011 and 2016, the NSA said.

    “Oops, sorry!”

    1. The National Security Agency destroyed surveillance data it pledged to preserve in connection with pending lawsuits and apparently never took some of the steps it told a federal court it had taken to make sure the information wasn’t destroyed, according to recent court filings.

      Back in my day lying to a federal court was considered a big deal.

    1. Good article. Thanks, Crustmeister.

  19. This is from so long ago I lost the citation:
    Adviser Daniel Patrick Moynihan, notable as a Democrat in the administration, urged the administration to initiate a worldwide system of monitoring carbon dioxide in the atmosphere, decades before the issue of global warming came to the public’s attention.
    There is widespread agreement that carbon dioxide content will rise 25 percent by 2000, Moynihan wrote in a September 1969 memo.
    “This could increase the average temperature near the earth’s surface by 7 degrees Fahrenheit,” he wrote. “This in turn could raise the level of the sea by 10 feet. Goodbye New York. Goodbye Washington, for that matter.”
    Wrong then (1969), wrong now (2018). “Widespread” agreement does not constitute truth; see flat earth.
    I was taught that carbon dioxide was necessary for plant life; has that changed?

    1. Pretty much everybody here agrees that the models over-estimate.

      And nobody said CO2 is not necessary for plants.

      1. Some people pay a great deal of money to supplement CO2 for their indoor cash crops.

  20. The current level of carbon dioxide in the atmosphere is around 403 parts per million. Carbon dioxide in the atmosphere is now increasing annually at about 3 parts per million. If that rate of increase keeps up, the amount of carbon dioxide in the atmosphere will double by the end of the century.

    There are 83 years left in the 21st century, If the current level of CO2 is 403 ppm, and it increases by 3 ppm for 83 years, the level at the end of the century will be 403 + (3 * 83) = 652 ppm, which is not double 403.

    Also, how does anyone know what the pre-industrial level was? Doesn’t being pre-industrial pretty much mean, by definition, that the technology to make such measurements didn’t exist?

    1. Dan s. – good questions. with real answers.
      Scientists have drilled down into the ice on Antarctica and Greenland to date ice back 800,000 years. In this they have measured trapped air bubbles. The data in recent times overlaps with direct measurements. Data between cores overlaps nicely. And from this we know that during interglacial warm periods like the one we were in before 1850 the concentration of CO2 in the atmosphere was typically 250 to 285 ppm. Using 280 as a baseline pre-industrial (from the ice cores) then 560 would be “double” the baseline. You’d have to talk to the author to understand exactly what he meant though.

  21. Fictional things tend to be harmless.

  22. Shouldn’t Mikey give back the 2 MILLION DOLLAR GRANT cuz he failed to “HIDE THE DECLINE”?

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