The consequences of human-induced climate change are becoming increasingly evident, as atmospheric CO2 levels continue to rise due to our relentless emissions.
Thank you for the comprehensive article. Sadly though, I sense we are “whistling past the graveyard” in our hubris of control. In psychology, there is a well-documented tendency to imagine we have much more control over random outcomes than reality dictates.
Humans tend to be eternal, optimists even when there is no evidence to support such Pollyantics. Youmadmitmthatmyour data and models are speculations since we have no historical hard facts to rely on. Might this simply be an example of our collective “illusion of control” when we might be wiser to assume the worst-case scenario and embrace our likely doom?
Gestalt psychologist Fritz Perls started: “Nothing changes until it becomes what it actually is.” There is no silver bullet to slay the beast, no world governmental white knight coming to make us all behave and save the day. As we inch toward a world human population of 10 billion or more, the consequences will be increasingly evident and probably not in a tidy linear manner. Wisdom would dictate that we assume the worst-case scenario and make preparations erring on the side of caution. Reality may nat look anything like our rosy models and it would be nice to have a ‘plan B.’
Under the "good news" portion of this article you state that scientists have done a lot of modeling of methane feedbacks, etc and that it still shows a linear warming. I find this to be reductive and missing of the point, which in my view as an engineer, is this: the fact that climate change is a composite problem, a rather complex polycentric nonlinear system problem, the linearity of warming is much more of an input and not solely an output as implied by your statement. Linear warming can and will have many resulting, often cascading effects. The fact that the warming is linear does not mean the impacts of that warming are linear as well.
Further, have you ever and I do mean even once, read a scientific paper or article about a scientific paper that states: Climate Change Not As Bad As Previously Estimated....? In 15 years of reading scientific papers and countless articles, I have only seen a constant steady stream of the opposite. So whenever I hear scientists or journalists making claims from a position of 'fact from modeling' I do remind myself that we're all just doing the best we can. "All models are incorrect, but some are useful" is the phrase many scientists use to caveat their model findings.
So, no... linear warming is not good news. It is only part of a larger more complex polycentric nonlinear system.
I agree with you. I have very low confidence in the models’ carbon cycles because we just don’t have the data to test it. It certainly could be a lot worse than what the models say.
Thanks for pointing out these non-smokestack, non-tailpipe greenhouse gas sources. Are there any numbers about the size of these sources relative to overall annual emissions? And as for things getting out of control, I remember Harvard Prof. Michael McElroy’s summary of how the denial will go: they’ll say “It isn’t true;” then “It’s too expensive to do anything about it;” and finally “It’s too late!”
The worst case here is inevitable without near term political revolution. We know that this is how mass extinctions occur. We don't know exactly when we fall over this tipping point. Whenever it comes, people will be alive and concious, trying to survive in a world that is no longer under control. A world where human agency no longer has the power to direct the unfolding ecological collapse. Perhaps we are those people and don't know it yet, perhaps our mythology of agency (we must work together for Net Zero) is a lie and it's already too late. You can't rule it out.
One thing is for sure... to the extent that humans have impact, the great majority of it is happening in Asia, which accounted for 60% of world CO2 emissions as of 2021, up from about 38% in 2002. Any reasonable projection show Asian countries continuing to emit huge and increasing quantities of CO2 well into the future, even as the US and Europe reduce emissions. We in the west are increasingly inconsequential in this discussion.
It's not too early to give some thought to mitigating arctic CH4 emissions by promoting tundra microbiomes that metabolize it to CO2. As with agriculture, these can be surprisingly sensitive to trace element availability, allowing the use of affordable micronutrient fertilizers
I would like to know what you two think of this piece. I find it troubling. Especially this line and related references. "Publication and truth are thus not synonymous—not even close." The second reference is especially bothersome, with a title of "Why most published research findings are false."
Having worked with research scientists at a national laboratory for 34 years in the fields of high energy density physics and fusion, I find such a claim insulting.
I have seen the Galileo comparison as well but usually by non-scientists. I don't think that comparison is relevant at all to our situation today.
The fundamental point is one I agree with: science can tell us things that are true about the world and tell us what future climate might look like under various scenarios, but it can't tell us what we should do about it. That said, claiming the mantle of science for your preferred policy is one of the most powerful rhetorical arguments in policy debate. Their pleas to policymakers to stop saying "the science says" is like telling a politician "please don't lie." No one will listen to them & this argument will have literally zero impact.
Thanks. I guess I'm more upset by this article than you are.
I still feel that by impugning the science or process of determining decarbonization pathways or timelines he inadvertently impugns the science behind climate change and science in general. Further, even though science can't tell us the optimal decarbonization path it can tell us something about the urgency - "every tenth of degree matters." Maybe science can't say something optimal decarbonization pathways but experts can. They can do system studies and as Zeke pointed out in Congressional Testimony on 3/12/21,
"These decarbonization models give us a sense of what may be needed. We should not fixate too much on the specific generation mixes in any particular scenario, but we should take heed of where the models agree: on the importance of near-term renewables deployment, the medium-term role of gas capacity to fill in the gaps, and the importance of clean firm generation and complementary technologies to wean the power system off its dependence on natural gas in the longer term."
Bottom line: I would much rather have Zeke testifying to Congress than Patrick.
Have you looked at Simon Sharpe's 'Five Times Faster' book? The way you're describing the risks at the end of your article reminds me strongly of this. Interested in your thoughts if you've read it - has our approach to AGW really been as risk-blind as Simon suggests?
Isn't that the exact opposite of what this realclimate article says?
"The AMOC has a tipping point, but it is highly uncertain where it is."
and
"the Atlantic Multidecadal Variability may now be approaching a tipping point after which the Atlantic current system might undergo a critical transition."
About Figure ‘temperature and CO2 over the past 400,000 years’, I can’t see the temperature rise before CO2 increases. Would you explain how to read these graphs to see your point?
Yeah, that’s hard to see in the photo. The short answer is that you can sort of see it there, but people done more sophisticated analysis, and see it more clearly.
Climate denier the late Prof Bob Carter's lectured, "See how the CO2 level rises BEFORE the temperature", and I puzzled over this for years.
CO2 is a forcing and a feedback. In the past, at times there has been a little warming, which releases CO2, that causes more warming and so on ... fairly slowly.
Humanity has now caused a massive increase in CO2 and we see immediate and rapid warming so the feedback element seen "normally" is overwhelmed.
Please realise if you tell me that this is nonsense then you must give a better answer or I will have sleepless nights again forever!!!
I knew Bob Carter at Otago U in the early 1960s, but didn't have anything to do with him until later life - he was a former Cambridge U friend of close friends of mine and I saw quite a bit of him, enough to realise he was talking twaddle and I called him out.
By the way, thank Zeke Hausfather, this is a treasure chest:
Thank you for the comprehensive article. Sadly though, I sense we are “whistling past the graveyard” in our hubris of control. In psychology, there is a well-documented tendency to imagine we have much more control over random outcomes than reality dictates.
Humans tend to be eternal, optimists even when there is no evidence to support such Pollyantics. Youmadmitmthatmyour data and models are speculations since we have no historical hard facts to rely on. Might this simply be an example of our collective “illusion of control” when we might be wiser to assume the worst-case scenario and embrace our likely doom?
Gestalt psychologist Fritz Perls started: “Nothing changes until it becomes what it actually is.” There is no silver bullet to slay the beast, no world governmental white knight coming to make us all behave and save the day. As we inch toward a world human population of 10 billion or more, the consequences will be increasingly evident and probably not in a tidy linear manner. Wisdom would dictate that we assume the worst-case scenario and make preparations erring on the side of caution. Reality may nat look anything like our rosy models and it would be nice to have a ‘plan B.’
Under the "good news" portion of this article you state that scientists have done a lot of modeling of methane feedbacks, etc and that it still shows a linear warming. I find this to be reductive and missing of the point, which in my view as an engineer, is this: the fact that climate change is a composite problem, a rather complex polycentric nonlinear system problem, the linearity of warming is much more of an input and not solely an output as implied by your statement. Linear warming can and will have many resulting, often cascading effects. The fact that the warming is linear does not mean the impacts of that warming are linear as well.
Further, have you ever and I do mean even once, read a scientific paper or article about a scientific paper that states: Climate Change Not As Bad As Previously Estimated....? In 15 years of reading scientific papers and countless articles, I have only seen a constant steady stream of the opposite. So whenever I hear scientists or journalists making claims from a position of 'fact from modeling' I do remind myself that we're all just doing the best we can. "All models are incorrect, but some are useful" is the phrase many scientists use to caveat their model findings.
So, no... linear warming is not good news. It is only part of a larger more complex polycentric nonlinear system.
I agree with you. I have very low confidence in the models’ carbon cycles because we just don’t have the data to test it. It certainly could be a lot worse than what the models say.
Thanks for pointing out these non-smokestack, non-tailpipe greenhouse gas sources. Are there any numbers about the size of these sources relative to overall annual emissions? And as for things getting out of control, I remember Harvard Prof. Michael McElroy’s summary of how the denial will go: they’ll say “It isn’t true;” then “It’s too expensive to do anything about it;” and finally “It’s too late!”
The worst case here is inevitable without near term political revolution. We know that this is how mass extinctions occur. We don't know exactly when we fall over this tipping point. Whenever it comes, people will be alive and concious, trying to survive in a world that is no longer under control. A world where human agency no longer has the power to direct the unfolding ecological collapse. Perhaps we are those people and don't know it yet, perhaps our mythology of agency (we must work together for Net Zero) is a lie and it's already too late. You can't rule it out.
One thing is for sure... to the extent that humans have impact, the great majority of it is happening in Asia, which accounted for 60% of world CO2 emissions as of 2021, up from about 38% in 2002. Any reasonable projection show Asian countries continuing to emit huge and increasing quantities of CO2 well into the future, even as the US and Europe reduce emissions. We in the west are increasingly inconsequential in this discussion.
Thank you once more for a well written and topical essay. ZF.
Therefore: urgent need for net taxation of net CO2 emissions which visually NO climate change "activists" are advocating?
It's not too early to give some thought to mitigating arctic CH4 emissions by promoting tundra microbiomes that metabolize it to CO2. As with agriculture, these can be surprisingly sensitive to trace element availability, allowing the use of affordable micronutrient fertilizers
Oh no, please no! We humans have left a trail of destruction through tinkering with the environment via blinkered and siloed science. Please no....
The models are not just uncertain about arctic response. they also fail low in reproducing pliocene conditions (under current GHG levels!) https://cp.copernicus.org/articles/16/2325/2020/cp-16-2325-2020.pdf
Zeke and Andrew,
This is a little tangent to the discussion, but I just came across an article by Patrick Brown, https://thebreakthrough.org/journal/climate-change-banned-words/science-climate-change .
I would like to know what you two think of this piece. I find it troubling. Especially this line and related references. "Publication and truth are thus not synonymous—not even close." The second reference is especially bothersome, with a title of "Why most published research findings are false."
Having worked with research scientists at a national laboratory for 34 years in the fields of high energy density physics and fusion, I find such a claim insulting.
I have seen the Galileo comparison as well but usually by non-scientists. I don't think that comparison is relevant at all to our situation today.
Again, I would appreciate hearing what you think.
Thanks,
Dean
The fundamental point is one I agree with: science can tell us things that are true about the world and tell us what future climate might look like under various scenarios, but it can't tell us what we should do about it. That said, claiming the mantle of science for your preferred policy is one of the most powerful rhetorical arguments in policy debate. Their pleas to policymakers to stop saying "the science says" is like telling a politician "please don't lie." No one will listen to them & this argument will have literally zero impact.
Thanks. I guess I'm more upset by this article than you are.
I still feel that by impugning the science or process of determining decarbonization pathways or timelines he inadvertently impugns the science behind climate change and science in general. Further, even though science can't tell us the optimal decarbonization path it can tell us something about the urgency - "every tenth of degree matters." Maybe science can't say something optimal decarbonization pathways but experts can. They can do system studies and as Zeke pointed out in Congressional Testimony on 3/12/21,
"These decarbonization models give us a sense of what may be needed. We should not fixate too much on the specific generation mixes in any particular scenario, but we should take heed of where the models agree: on the importance of near-term renewables deployment, the medium-term role of gas capacity to fill in the gaps, and the importance of clean firm generation and complementary technologies to wean the power system off its dependence on natural gas in the longer term."
Bottom line: I would much rather have Zeke testifying to Congress than Patrick.
Have you looked at Simon Sharpe's 'Five Times Faster' book? The way you're describing the risks at the end of your article reminds me strongly of this. Interested in your thoughts if you've read it - has our approach to AGW really been as risk-blind as Simon suggests?
Other people have mentioned the book and it has been on my list. I guess I really need to read it sooner rather than later.
Is there a specific reason you characterize collapse of AMOC as "unlikely"?
It’s mainly because the models don’t predict it. They show that out decreases essentially linearly overtime as the climate warms. For a deeper dive, see this: https://www.realclimate.org/index.php/archives/2023/07/what-is-happening-in-the-atlantic-ocean-to-the-amoc/
Isn't that the exact opposite of what this realclimate article says?
"The AMOC has a tipping point, but it is highly uncertain where it is."
and
"the Atlantic Multidecadal Variability may now be approaching a tipping point after which the Atlantic current system might undergo a critical transition."
About Figure ‘temperature and CO2 over the past 400,000 years’, I can’t see the temperature rise before CO2 increases. Would you explain how to read these graphs to see your point?
Yeah, that’s hard to see in the photo. The short answer is that you can sort of see it there, but people done more sophisticated analysis, and see it more clearly.
Climate denier the late Prof Bob Carter's lectured, "See how the CO2 level rises BEFORE the temperature", and I puzzled over this for years.
CO2 is a forcing and a feedback. In the past, at times there has been a little warming, which releases CO2, that causes more warming and so on ... fairly slowly.
Humanity has now caused a massive increase in CO2 and we see immediate and rapid warming so the feedback element seen "normally" is overwhelmed.
Please realise if you tell me that this is nonsense then you must give a better answer or I will have sleepless nights again forever!!!
I knew Bob Carter at Otago U in the early 1960s, but didn't have anything to do with him until later life - he was a former Cambridge U friend of close friends of mine and I saw quite a bit of him, enough to realise he was talking twaddle and I called him out.
By the way, thank Zeke Hausfather, this is a treasure chest:
https://www.carbonbrief.org/state-of-the-climate-2023-now-likely-hottest-year-on-record-after-extreme-summer/
Sorry, my brain not working so early in morning. Carter's lectures claimed:
Temperature rise BEFORE CO2 level.