Perhaps there really ought to be a Trump World scenario?
One of Donald Trump’s first actions after taking over the U.S. Presidency in 2024 was to once again to take the United States out of the Paris Agreement (see Box). Although that takes a year to become effective, it is already having consequences, especially for the Intergovernmental Panel on Climate Change (IPCC) as it plans ongoing and future reports. Because the United States is both a leading world power and major contributor to climate change (along with China and Europe), it should do its part to reduce greenhouse gas emissions and plan for the consequences. Funding under the Biden administration was a real shot in the arm for addressing climate change, but the Trump years loom ominously. Indeed, America’s lack of support for climate science poses a serious problem for the survival of our species. Human climate change already costs hundreds of billions of dollars each year.
In the first Trump administration, “climate” disappeared from government websites and calls for research proposals. But now human-induced climate change is even more firmly and strongly established as a factor in increasing extremes of climate of all sorts. The ability to track what is happening and why, and issue appropriate warnings has improved enormously since the first Trump era, but is in serious jeopardy from loss of expertise and funding. Changes to and elimination of government departments, arbitrarily chopping off already allocated funding, firing incoming new recruits and getting rid of older staff, and culling numerous informative websites are also having consequences. Many grants and loans have been frozen. There is no transition and no measured assessment or evaluations to justify the actions taken!Climate action has been a unifying force for social justice, racial equality, women's opportunities, children's rights, protection of ancestral lands, and the health of both humans and ecosystems, and the dismantling of DEI in the United States (diversity, equity and inclusion), even if its implementation had been flawed in places (such as through reverse discrimination), will have major long-term consequences.
All too often Trump and his cohorts have used outright lies and distortion of facts as a basis for actions that have frequently been inhumane at best. The appointment of so many cronies has left incompetent decision makers across the government who have vowed to get even and impose purely vindictive penalties. The attacks on those who have stood up in the past has been extraordinarily blatant and many individuals and companies have bowed to pressures rather than speaking up and becoming a target. The US has lost its place as a law abiding country. Science facts are ignored, and the major threats to the planet outlined clearly by climate scientists have been disavowed, based on nothing but ideology.
Trump has declared numerous emergencies (on energy, government waste, foreign trade, etc) none of which remotely qualify, but no emergency where there really is one on global climate change. The consequences of increasing disasters are not only increasing prices, but homeowners suffer from increasing or no insurance and falling property values in disaster-prone areas. It has been very discouraging to see the lack of integrity of many Republican politicians and industry leaders who have bowed to the changes underway.
"Climate action has been a unifying force for social justice, racial equality, women's opportunities, children's rights, protection of ancestral lands, and the health of both humans and ecosystems"
I suspect that wrapping so many issues into a type of 'solidarity' mantra will continue to be the achilles heel which limits ability to take any of these issues in particular seriously. It really has become a blunted haze of political activism without any particular punch at all.
Seems like a self-fulfilling prophecy to me. I don't necessarily disagree, however. Regardless, in a pluralistic democracy, coalition building is inevitable. I was marginally encouraged by news coverage of the "Hands Off!" protests around the US on Saturday. But as always, subjectivity degrades accurate apprehension of reality. "The first rule is you must not fool yourself, and you are the easiest person to fool": hey, I resemble that remark 8^|. Who among us claims to have their finger on the pulse of the voters, as it were? I'm skeptical!
"once again to take the United States out of the Paris Agreement " Oh no, not the wholly ineffectual "opiate of the masses" do-nothing paris agreement?! how will we pretend to care now?
"Funding under the Biden administration was a real shot in the arm for addressing climate change" yeah, producing more oil and gas thn any country in history really helped address climate change
"protection of ancestral lands" this sort of ethnonationalism is literally a nazi ideology, maybe e should be supporting nazi ideologues, yeah?
" dismantling of DEI in the United States" oh no, the racist is upset that racism is less legal than it used to be
Oh, the bitterness, sob! Nihilism is tempting, because life sucks. Nihilists have no concept of sucking more or less, however. If the global economy decarbonizes, life will still suck in all kinds of ways, but changing climate will no longer be one of them. IMHO, "perfect" is the enemy of "sucking less". YMMV.
"If the global economy decarbonizes" and whats the time table of complete decarbonization of the entire economy and CCS for all the excess carbon we put in the atmosphere? Couple weeks? A month or two.
"but changing climate will no longer be one of them." Even if we did stop every carbon emission source today, the damage is already done, it just takes time for the effects to be felt.
"IMHO, "perfect" is the enemy of "sucking less"" your opinion is based on ignorance. Is getting shot by 99 bullets better than getting shot by 100? After all we have to be happy with "sucking less".
From The Guardian (2 April 2025): “Recent reports by Morgan Stanley, JPMorgan Chase and the Institute of International Finance all make clear the finance sector considers the Paris climate agreement limiting global temperatures, signed a decade ago by nearly 200 nations, is effectively dead and investors should plan accordingly.
“ ‘We now expect a 3C world,’ states a March analysis by Morgan Stanley.”
But they see a growth opportunity in the air conditioning industry. I wonder if they’re thinking about hurricanes, floods, and other “opportunities.”
I read MS research but missed that...will look now but your comment here is a terrific one. Why so little press on it? Like Carbon Brief or Real Climate? Thanks!
Correct me if I'm wrong, but the models you are quoting ignore many relevant facts, such as:
- The models exclude AMOC turning off, and the consequences.
- The models exclude the recent and accelerating methane releases, both on land as permafrost melts, and now the increasing releases of the potentially massive methane clathrates under the Arctic and Antarctic glaciers as they retreat.
- CO2(e) levels are NOT plateauing, and fossil fuel use is only running into resource constraints, not voluntary or technical consumption reductions.
- Trump is just one of many governments planning an expansion of fossil mining, including Canada, Britain, Australia, India and China.
- Solar and wind has generally been in addition to fossil fuels to supply additional demand, and has not replaced fossil fuel usage.
All of which (and more) suggests to me that the modelling you are quoting is now seriously flawed, and already it's previous projections for 'now' are incorrect - global land, sea and air temperatures are already well above the previous model's predictions.
May I point out that the last time CO2 levels were this high, before humans existed, the planet 's temperature was far higher, the poles were ice free, sea levels were tens of metres higher and there were forests on the Antarctic land mass! And that at those temperatures, humans could not have survived. What is it that you suggest will break that historic link?
Lastly, please explain to me the logic of why global temperatures will stop rising, despite so many feedback mechanisms of considerable scale (like methane clathrates, for example) that are likely to increase or accelerate heating, and so few that might reduce it.
We are in strong agreement that socio-economic scenarios should be current, not based on assumptions of the 1990s. I'll leae it to Zeke to respond on the ESM comments. And yes, both mitigation and adaptation are important.
AFAICT, Dr. Trenberth is in favor of collective action to reduce the trend of atmospheric CO2 concentration to zero ASAP. How are your objections relevant to that? In any case, he's hardly obliged to walk you through the science. You can look this stuff up yourself, but keep in mind that not all sources carry the same epistemological weight.
As it would be impossible for any Western country to cut emissions to net zero in the next 30 years, even if they wanted to, without collapsing the economies, banking, currency and international debts, let alone the simple fact that no-one would vote for it in any democracy, then his entire argument falls at the first hurdle.
And yes, I am very aware of the science, I've been tracking it in detail since the Club of Rome in 1972, and I used to teach it before I retired.
Huh? Who said anything about 30 years? Do you think that's some kind of cutoff? The OP is about how global warming could be worse than it is now. Are you saying it's as bad as it can be already?
Moving on: AFAICT, you're confident the global economy can't be decarbonized by collective action in time. How are you so sure? I've been tracking the multiple overlapping common-pool-resource tragedies afflicting human society and the biosphere for about as long as you have. It's indisputable that the sooner our emissions reach zero, the lower the cumulative cost of warming will be. But however bad it gets, as long as there's profit to be made by transfer fossil carbon to the atmosphere by the gigatonne, it will never be too late to stop the tragedy from being even worse! That will require collective intervention in the otherwise-"free" market, for which history offers many examples, albeit none of this magnitude.
Lacking supernatural foresight, IMHO the quantitative uncertainties around credible projections leave room for optimism. Collective decarbonization will necessarily be decremental, but is already underway around the world. Frankly, it's not happening fast enough to suit me either, but slow is better than never. Yes, reaching zero emissions by collective intervention in the global energy market may well take longer than 30 years, but every decrement reduces the rate of warming below what it *would otherwise be* without collective action. Once again: perfect is the enemy of better-than-it-would-be-otherwise!
Ok, enough. I think you are delusional, and whilst you are entitled to your views, I have no interest in your further education, not least because you won't listen anyway.
Sure. It's clear nothing will dissuade you from your views, either. But if you keep evincing *unwarranted* (IMHO) confidence in your projected future timeline, I'll probably keep pushing back, because you're not my only audience.
Well I'll be an outlier and continue to stubbornly insist that we are headed for a very hot planet and that it's coming sooner than expected. But what do I know? Almost nothing.
Apparently, Zeke, you have NOT read the articles on C3S, including the 6-5-24 "Hottest May on record spurs call for climate action", or the 2-3-25 Hansen, etal, "Global Warming Has Accelerated", both of which document 0.2 degC ANNUAL GAST increases, and, thus, portent a 3 degC increase over the 1991-2020 baseline by 2032, and an extinction level 5 degC increase by 2042, 17 yrs. hence. I recommend these state of the art articles to readers, and that they ignore your bizarre article.
trump is planning the worse consequences of returning to full extraction of fuel, only for immediate profits for a handful lunatic billionaires no matter what.
Until scalable carbon capture technology is implemented, global warming and sea levels will continue to rise. There is now no known way of scaling carbon capture to bring atmospheric levels down to pre-industrial conditions, and until then, global warming will continue.
According to Dr. Hausfather (https://www.carbonbrief.org/explainer-will-global-warming-stop-as-soon-as-net-zero-emissions-are-reached/), once global fossil carbon emissions reach zero, global mean surface temperature will stabilize around the value it has reached by then. That's because natural CO2 drawdown will roughly balance long-term feedbacks to previous CO2 radiative forcing. Therefore, the warming up to that point will not reverse, but won't keep on rising either. Sea level will continue to rise, however, as ice melts due to the warming to date. And human societies will have to adapt to a world that's 3°C warmer than it was 100 years ago.
Can you explain why you “see a fossil fuel-heavy world as much more likely associated with poverty, isolationism, and low rates of technological development”? None of that seems consistent with the fossil fuel-heavy world of the past 150 years, which has resulted in dramatically reduced poverty and spectacular technological development. I’m not arguing that we necessarily need fossil fuels to achieve those things; we won’t if we can actually develop satisfactory substitutes. But it isn’t at all clear why you apparently think continued use of fossil fuels will somehow cause a reversal of all trends to date.
SSP3, for reasons you highlight and more, is not a plausible scenario.
It is every bit as implausible as SSP5
Consider that SSP3 has:
* an increase in per capita coal consumption of 2.2x
* no reduction in carbon intensity of energy
* large slowdown in improvements to energy intensity of the economy
* baseline radiative forcing of 7.0 W/m^2
* large expansion of cropland and pastures
* Increasing NOx and SO2 emissions
* ~doubling of CO2 and CH4 emissions
* a global population of ~13 billion in 2100
While a "Trump World" scenario might be interesting to develop, SSP3 is not that scenario as none of the above are plausible assumptions in the real world. They might be fun to model for an exploratory analysis.
The creators of SSP3 warned that they were assuming the "worst-case" (as view from 20 years ago) to create a scenario with the largest possible obstacles to both mitigation and adaptation for sensitivity analyses, and not creating a projection of a plausible future:
"Researchers must ensure that they do not overstate the problem by only showing this worst-case scenario, because providing biased information could be more harmful than beneficial in policy making"
Any new scenario that replicates assumptions of SSP3 and represented as a plausible future will set the community back for years to come, see:
I find the narrative of SSP3 interesting more than the socioeconomics (particularly the population, though the low GDP growth is more plausible).
That being said, assumptions around coal and other energy sources are an output of IAMs using SSP3 socioeconomic assumptions, not inherent in SSP3 itself.
My general point is that current policies are neither a ceiling nor a floor on future emissions, and its quite possible to envision a world where clean energy deployment slows down as domestic fossil resources are prioritized (after all, as of today coal is now a "critical mineral" in the US...).
Fair enough, Dr. Pielke/Voldemort, but I found both Zeke's and Kevin's remarks a useful reminder of what can happen without targeted collective intervention. IMHO, that message needs to be reinforced in the run-up to the US midterm elections.
What are you using for up-to-date US LNG export projections and their climate impact? If we consider that long-term LNG contracts for US LNG are being signed in Asia through tariff coercion, that growth would not be factored in yet...how big might it be? Additionally, to what degree is the Howarth vs GREET lifecycle emissions (and GWP 20 vs 100 for methane) resolved within the modeling community? I think I know...but stories of "US LNG no climate impact" proliferate and are worrisome. Related to these, might the US-Russia thaw result in > natural gas combustion (pipeline or LNG) if sanctions dissolve among more nations? I ask these questions with more of a 2040 focus than 2100 out of concern for path dependence, like LNG importers who don't upgrade grids for renewables or more Venture Global IPOs (bad as it was) that face growth pressure then apply political pressure in response. Thanks.
GWPs (both 20 and 100) are a pretty poor indicator of actual temperature response over a period of time. You need a proper climate model (or a more complex metric like GWP*) to resolve that.
but can you say if climate models should use Howarth's (long standing) LCA leakage parameters or ANL's GREET, or something else? And, just a comment, but it seems climate change and US LNG have de-linked in both literature and press, which is disturbing...
This is a very helpful overview of the climate crisis. Does switching from coal to natural gas assist in reducing CO2 emissions? In Australia - a major exporter of LNG - many environmentalists do not accept that it helps lower emissions.
I get asked that a lot. My response is that switching from coal to natural gas is like going from two packs of cigarettes per day to one pack per day. No doubt it's a beneficial move, but you are still harming yourself. Best to to go zero packs per day (e.g., switching off natural gas).
not necessarily so if a few smokes provides someone with the joie de vivre. it really is a value judgement. The scientism of health optimization really seems to miss the meaning of life altogether. Never has nature demonstratred any inherent drive toward such ideals. Ironically, meddling in that must result in unintended consequences, which are afterall not optimal at all. Are people happier, healthier, and more productive than years past? I have my doubts.
Heh. Written like a defensive smoker. IMHO you're right that optimality is a value judgement, but trends in some objective metrics of human well-being are positive. Lifespan, for example. According to OWID (https://ourworldindata.org/life-expectancy):
"Across the world, people are living longer.
"In 1900, the average life expectancy of a newborn was 32 years. By 2021 this had more than doubled to 71 years."
I will turn 72 next month. All my subsequent lifespan will be beating the odds! Seriously, though: how many years I owe to my successful struggle to quit smoking tobacco 42 years ago, isn't worth the effort to know. Statistically however, it appears to make a big difference in lifespan (e.g. https://evidence.nejm.org/doi/full/10.1056/EVIDoa2300272).
In my first-hand yet irreducibly subjective experience, self-destructive behavior is often successful, and choosing to avoid destroying oneself enables greater individual happiness, health and productivity than the alternative. YMMV, as we said when the Internet was new.
if the analogy has confused you, because you have feelings about smoking based on your own personal experience, that's completely understandable. At any rate, nature does not provide any examples of successful or sustainable outcomes through bureaucratic mandates. The hidden dependencies must always result in unintended consequences. True optimality arises only through immensely complex feedbacks. Nature thrives precisely because it lacks a central planner. At the surface, the carnage and perceived horror in its checks and balances might seem disturbing to us. However, confusion may arise when we think that we can stand apart from it and impose order based on our own value judgements. When we try to solve perceived problems through technocratic, top-down interventions, often framed through the relatively new lens of scientism, we may unintentionally accelerate our own demise. I realize this is a radical perspective. But it’s hard to ignore that it is precisely since the rise of modern science, academia, and its close ties to centralized global governance that nature’s equilibrium has become increasingly disrupted. We now find ourselves chasing and extinguishing the very fires we’ve inadvertently lit, with no end in sight for this spiral.
When you said "if a few smokes provides someone with the joie de vivre", I assumed you were speaking from experience: my bad. Your reply is well-written and thought-provoking. Nonetheless, my comments about self-destructive individual behavior apply to our aggregate welfare as well. Under the mediocrity principle (https://www.edge.org/response-detail/11272), "true optimality" is unattainable, but melioration is often within reach. IOW, "perfect" is the enemy of "less bad".
You presumably know that anthropogenic global warming is a tragedy of the commons: the result of the global "free" market's ancient propensity to socialize as much transaction cost as it can get away with. Because producers and consumers both privately benefit by socializing part of their marginal cost out of the market price, only collective intervention, i.e. "mutual coercion, mutually agreed upon" (G. Hardin) can put a cap on the rising cost of global warming in money and grief, already being paid by involuntary 3rd parties, often out of proportion to their private emissions.
Yet collective intervention aimed at decarbonizing national economies need not be "technocratic" nor centrally controlled. For example, a flat fee per tonne of carbon, taken from producers where it enters the national economy, if well-crafted by Congress (work with me, OK?), would tilt the production of all goods and services toward carbon-neutral alternative energy sources (https://citizensclimatelobby.org/price-on-carbon/). Metaphorically, it would be a nudge to the "invisible hand" of the free market by the "visible hand" of collective intervention. History is replete with successful examples: indeed, the vast profits to the fossil fuel industry today are enhanced by over a century of government intervention on its behalf.
With a corrected price signal for fossil carbon, market forces can build out the carbon-neutral global economy, until emissions reach zero. At that point, all other causes of ecological, economic, and social instability will still be present, but a constantly changing climate won't be one of them anymore. YMMV, but IMO that's less bad than open-ended warming is.
In the USA, the hard part is to persuade enough voters that collective action is necessary, when the only alternative is open-ended global warming and the relentlessly accumulating aggregate cost therefrom. And all we have to do is vote Democratic, as the default US party of collective action for collective benefit!
Depends on what you mean by "revolution". Speaking for myself, my street fighting days are over. My only hope is that enough US voters will realize they made a mistake last November, to at least retake the House in 2026.
Perhaps there really ought to be a Trump World scenario?
One of Donald Trump’s first actions after taking over the U.S. Presidency in 2024 was to once again to take the United States out of the Paris Agreement (see Box). Although that takes a year to become effective, it is already having consequences, especially for the Intergovernmental Panel on Climate Change (IPCC) as it plans ongoing and future reports. Because the United States is both a leading world power and major contributor to climate change (along with China and Europe), it should do its part to reduce greenhouse gas emissions and plan for the consequences. Funding under the Biden administration was a real shot in the arm for addressing climate change, but the Trump years loom ominously. Indeed, America’s lack of support for climate science poses a serious problem for the survival of our species. Human climate change already costs hundreds of billions of dollars each year.
In the first Trump administration, “climate” disappeared from government websites and calls for research proposals. But now human-induced climate change is even more firmly and strongly established as a factor in increasing extremes of climate of all sorts. The ability to track what is happening and why, and issue appropriate warnings has improved enormously since the first Trump era, but is in serious jeopardy from loss of expertise and funding. Changes to and elimination of government departments, arbitrarily chopping off already allocated funding, firing incoming new recruits and getting rid of older staff, and culling numerous informative websites are also having consequences. Many grants and loans have been frozen. There is no transition and no measured assessment or evaluations to justify the actions taken!Climate action has been a unifying force for social justice, racial equality, women's opportunities, children's rights, protection of ancestral lands, and the health of both humans and ecosystems, and the dismantling of DEI in the United States (diversity, equity and inclusion), even if its implementation had been flawed in places (such as through reverse discrimination), will have major long-term consequences.
All too often Trump and his cohorts have used outright lies and distortion of facts as a basis for actions that have frequently been inhumane at best. The appointment of so many cronies has left incompetent decision makers across the government who have vowed to get even and impose purely vindictive penalties. The attacks on those who have stood up in the past has been extraordinarily blatant and many individuals and companies have bowed to pressures rather than speaking up and becoming a target. The US has lost its place as a law abiding country. Science facts are ignored, and the major threats to the planet outlined clearly by climate scientists have been disavowed, based on nothing but ideology.
Trump has declared numerous emergencies (on energy, government waste, foreign trade, etc) none of which remotely qualify, but no emergency where there really is one on global climate change. The consequences of increasing disasters are not only increasing prices, but homeowners suffer from increasing or no insurance and falling property values in disaster-prone areas. It has been very discouraging to see the lack of integrity of many Republican politicians and industry leaders who have bowed to the changes underway.
Just when you thought things couldn't get worse, Trump signed four executive orders yesterday to keep coal plants alive and burn more coal, https://www.nytimes.com/2025/04/09/climate/trump-executive-orders-coal.html?unlocked_article_code=1.-U4.rdU8.r9r0gzrpQS1N&smid=url-share .
I mean I'm willing to have discussions about the necessity of natural gas as a transition energy source but only if it displaces coal. Unbelievable.
"Climate action has been a unifying force for social justice, racial equality, women's opportunities, children's rights, protection of ancestral lands, and the health of both humans and ecosystems"
I suspect that wrapping so many issues into a type of 'solidarity' mantra will continue to be the achilles heel which limits ability to take any of these issues in particular seriously. It really has become a blunted haze of political activism without any particular punch at all.
Seems like a self-fulfilling prophecy to me. I don't necessarily disagree, however. Regardless, in a pluralistic democracy, coalition building is inevitable. I was marginally encouraged by news coverage of the "Hands Off!" protests around the US on Saturday. But as always, subjectivity degrades accurate apprehension of reality. "The first rule is you must not fool yourself, and you are the easiest person to fool": hey, I resemble that remark 8^|. Who among us claims to have their finger on the pulse of the voters, as it were? I'm skeptical!
"once again to take the United States out of the Paris Agreement " Oh no, not the wholly ineffectual "opiate of the masses" do-nothing paris agreement?! how will we pretend to care now?
"Funding under the Biden administration was a real shot in the arm for addressing climate change" yeah, producing more oil and gas thn any country in history really helped address climate change
"protection of ancestral lands" this sort of ethnonationalism is literally a nazi ideology, maybe e should be supporting nazi ideologues, yeah?
" dismantling of DEI in the United States" oh no, the racist is upset that racism is less legal than it used to be
Oh, the bitterness, sob! Nihilism is tempting, because life sucks. Nihilists have no concept of sucking more or less, however. If the global economy decarbonizes, life will still suck in all kinds of ways, but changing climate will no longer be one of them. IMHO, "perfect" is the enemy of "sucking less". YMMV.
"If the global economy decarbonizes" and whats the time table of complete decarbonization of the entire economy and CCS for all the excess carbon we put in the atmosphere? Couple weeks? A month or two.
"but changing climate will no longer be one of them." Even if we did stop every carbon emission source today, the damage is already done, it just takes time for the effects to be felt.
"IMHO, "perfect" is the enemy of "sucking less"" your opinion is based on ignorance. Is getting shot by 99 bullets better than getting shot by 100? After all we have to be happy with "sucking less".
From The Guardian (2 April 2025): “Recent reports by Morgan Stanley, JPMorgan Chase and the Institute of International Finance all make clear the finance sector considers the Paris climate agreement limiting global temperatures, signed a decade ago by nearly 200 nations, is effectively dead and investors should plan accordingly.
“ ‘We now expect a 3C world,’ states a March analysis by Morgan Stanley.”
But they see a growth opportunity in the air conditioning industry. I wonder if they’re thinking about hurricanes, floods, and other “opportunities.”
I read MS research but missed that...will look now but your comment here is a terrific one. Why so little press on it? Like Carbon Brief or Real Climate? Thanks!
You couldn't write this stuff, could you? Probably invest in Undertakers and Funeral Directors, too. :-(
i got the report, as a 21 year MS alum...it was very upsetting
Correct me if I'm wrong, but the models you are quoting ignore many relevant facts, such as:
- The models exclude AMOC turning off, and the consequences.
- The models exclude the recent and accelerating methane releases, both on land as permafrost melts, and now the increasing releases of the potentially massive methane clathrates under the Arctic and Antarctic glaciers as they retreat.
- CO2(e) levels are NOT plateauing, and fossil fuel use is only running into resource constraints, not voluntary or technical consumption reductions.
- Trump is just one of many governments planning an expansion of fossil mining, including Canada, Britain, Australia, India and China.
- Solar and wind has generally been in addition to fossil fuels to supply additional demand, and has not replaced fossil fuel usage.
All of which (and more) suggests to me that the modelling you are quoting is now seriously flawed, and already it's previous projections for 'now' are incorrect - global land, sea and air temperatures are already well above the previous model's predictions.
May I point out that the last time CO2 levels were this high, before humans existed, the planet 's temperature was far higher, the poles were ice free, sea levels were tens of metres higher and there were forests on the Antarctic land mass! And that at those temperatures, humans could not have survived. What is it that you suggest will break that historic link?
Lastly, please explain to me the logic of why global temperatures will stop rising, despite so many feedback mechanisms of considerable scale (like methane clathrates, for example) that are likely to increase or accelerate heating, and so few that might reduce it.
I look forward to your response.
We are in strong agreement that socio-economic scenarios should be current, not based on assumptions of the 1990s. I'll leae it to Zeke to respond on the ESM comments. And yes, both mitigation and adaptation are important.
AFAICT, Dr. Trenberth is in favor of collective action to reduce the trend of atmospheric CO2 concentration to zero ASAP. How are your objections relevant to that? In any case, he's hardly obliged to walk you through the science. You can look this stuff up yourself, but keep in mind that not all sources carry the same epistemological weight.
As it would be impossible for any Western country to cut emissions to net zero in the next 30 years, even if they wanted to, without collapsing the economies, banking, currency and international debts, let alone the simple fact that no-one would vote for it in any democracy, then his entire argument falls at the first hurdle.
And yes, I am very aware of the science, I've been tracking it in detail since the Club of Rome in 1972, and I used to teach it before I retired.
Huh? Who said anything about 30 years? Do you think that's some kind of cutoff? The OP is about how global warming could be worse than it is now. Are you saying it's as bad as it can be already?
Moving on: AFAICT, you're confident the global economy can't be decarbonized by collective action in time. How are you so sure? I've been tracking the multiple overlapping common-pool-resource tragedies afflicting human society and the biosphere for about as long as you have. It's indisputable that the sooner our emissions reach zero, the lower the cumulative cost of warming will be. But however bad it gets, as long as there's profit to be made by transfer fossil carbon to the atmosphere by the gigatonne, it will never be too late to stop the tragedy from being even worse! That will require collective intervention in the otherwise-"free" market, for which history offers many examples, albeit none of this magnitude.
Lacking supernatural foresight, IMHO the quantitative uncertainties around credible projections leave room for optimism. Collective decarbonization will necessarily be decremental, but is already underway around the world. Frankly, it's not happening fast enough to suit me either, but slow is better than never. Yes, reaching zero emissions by collective intervention in the global energy market may well take longer than 30 years, but every decrement reduces the rate of warming below what it *would otherwise be* without collective action. Once again: perfect is the enemy of better-than-it-would-be-otherwise!
Ok, enough. I think you are delusional, and whilst you are entitled to your views, I have no interest in your further education, not least because you won't listen anyway.
Let's just leave it that we disagree.
Sure. It's clear nothing will dissuade you from your views, either. But if you keep evincing *unwarranted* (IMHO) confidence in your projected future timeline, I'll probably keep pushing back, because you're not my only audience.
Well I'll be an outlier and continue to stubbornly insist that we are headed for a very hot planet and that it's coming sooner than expected. But what do I know? Almost nothing.
Great update. I’d really love to see an IPCC Special Report on the impacts of +2.7C similar to the one that was compiled for +1.5C.
Apparently, Zeke, you have NOT read the articles on C3S, including the 6-5-24 "Hottest May on record spurs call for climate action", or the 2-3-25 Hansen, etal, "Global Warming Has Accelerated", both of which document 0.2 degC ANNUAL GAST increases, and, thus, portent a 3 degC increase over the 1991-2020 baseline by 2032, and an extinction level 5 degC increase by 2042, 17 yrs. hence. I recommend these state of the art articles to readers, and that they ignore your bizarre article.
The world is warming at around 0.24C per decade, not 0.2C per year. You appear to be a bit confused on the topic.
trump is planning the worse consequences of returning to full extraction of fuel, only for immediate profits for a handful lunatic billionaires no matter what.
Until scalable carbon capture technology is implemented, global warming and sea levels will continue to rise. There is now no known way of scaling carbon capture to bring atmospheric levels down to pre-industrial conditions, and until then, global warming will continue.
According to Dr. Hausfather (https://www.carbonbrief.org/explainer-will-global-warming-stop-as-soon-as-net-zero-emissions-are-reached/), once global fossil carbon emissions reach zero, global mean surface temperature will stabilize around the value it has reached by then. That's because natural CO2 drawdown will roughly balance long-term feedbacks to previous CO2 radiative forcing. Therefore, the warming up to that point will not reverse, but won't keep on rising either. Sea level will continue to rise, however, as ice melts due to the warming to date. And human societies will have to adapt to a world that's 3°C warmer than it was 100 years ago.
Can you explain why you “see a fossil fuel-heavy world as much more likely associated with poverty, isolationism, and low rates of technological development”? None of that seems consistent with the fossil fuel-heavy world of the past 150 years, which has resulted in dramatically reduced poverty and spectacular technological development. I’m not arguing that we necessarily need fossil fuels to achieve those things; we won’t if we can actually develop satisfactory substitutes. But it isn’t at all clear why you apparently think continued use of fossil fuels will somehow cause a reversal of all trends to date.
SSP3, for reasons you highlight and more, is not a plausible scenario.
It is every bit as implausible as SSP5
Consider that SSP3 has:
* an increase in per capita coal consumption of 2.2x
* no reduction in carbon intensity of energy
* large slowdown in improvements to energy intensity of the economy
* baseline radiative forcing of 7.0 W/m^2
* large expansion of cropland and pastures
* Increasing NOx and SO2 emissions
* ~doubling of CO2 and CH4 emissions
* a global population of ~13 billion in 2100
While a "Trump World" scenario might be interesting to develop, SSP3 is not that scenario as none of the above are plausible assumptions in the real world. They might be fun to model for an exploratory analysis.
The creators of SSP3 warned that they were assuming the "worst-case" (as view from 20 years ago) to create a scenario with the largest possible obstacles to both mitigation and adaptation for sensitivity analyses, and not creating a projection of a plausible future:
"Researchers must ensure that they do not overstate the problem by only showing this worst-case scenario, because providing biased information could be more harmful than beneficial in policy making"
Any new scenario that replicates assumptions of SSP3 and represented as a plausible future will set the community back for years to come, see:
https://rogerpielkejr.substack.com/p/climate-science-is-about-to-make
I find the narrative of SSP3 interesting more than the socioeconomics (particularly the population, though the low GDP growth is more plausible).
That being said, assumptions around coal and other energy sources are an output of IAMs using SSP3 socioeconomic assumptions, not inherent in SSP3 itself.
My general point is that current policies are neither a ceiling nor a floor on future emissions, and its quite possible to envision a world where clean energy deployment slows down as domestic fossil resources are prioritized (after all, as of today coal is now a "critical mineral" in the US...).
Fair enough, Dr. Pielke/Voldemort, but I found both Zeke's and Kevin's remarks a useful reminder of what can happen without targeted collective intervention. IMHO, that message needs to be reinforced in the run-up to the US midterm elections.
Ain't free speech grand?
Yes, policy matters! Agreed 100%
What are you using for up-to-date US LNG export projections and their climate impact? If we consider that long-term LNG contracts for US LNG are being signed in Asia through tariff coercion, that growth would not be factored in yet...how big might it be? Additionally, to what degree is the Howarth vs GREET lifecycle emissions (and GWP 20 vs 100 for methane) resolved within the modeling community? I think I know...but stories of "US LNG no climate impact" proliferate and are worrisome. Related to these, might the US-Russia thaw result in > natural gas combustion (pipeline or LNG) if sanctions dissolve among more nations? I ask these questions with more of a 2040 focus than 2100 out of concern for path dependence, like LNG importers who don't upgrade grids for renewables or more Venture Global IPOs (bad as it was) that face growth pressure then apply political pressure in response. Thanks.
GWPs (both 20 and 100) are a pretty poor indicator of actual temperature response over a period of time. You need a proper climate model (or a more complex metric like GWP*) to resolve that.
but can you say if climate models should use Howarth's (long standing) LCA leakage parameters or ANL's GREET, or something else? And, just a comment, but it seems climate change and US LNG have de-linked in both literature and press, which is disturbing...
This is a very helpful overview of the climate crisis. Does switching from coal to natural gas assist in reducing CO2 emissions? In Australia - a major exporter of LNG - many environmentalists do not accept that it helps lower emissions.
On balance it probably lowers emissions, but not by all that much. Better to skip coal/gas entirely and switch to renewables or nuclear.
I get asked that a lot. My response is that switching from coal to natural gas is like going from two packs of cigarettes per day to one pack per day. No doubt it's a beneficial move, but you are still harming yourself. Best to to go zero packs per day (e.g., switching off natural gas).
not necessarily so if a few smokes provides someone with the joie de vivre. it really is a value judgement. The scientism of health optimization really seems to miss the meaning of life altogether. Never has nature demonstratred any inherent drive toward such ideals. Ironically, meddling in that must result in unintended consequences, which are afterall not optimal at all. Are people happier, healthier, and more productive than years past? I have my doubts.
Heh. Written like a defensive smoker. IMHO you're right that optimality is a value judgement, but trends in some objective metrics of human well-being are positive. Lifespan, for example. According to OWID (https://ourworldindata.org/life-expectancy):
"Across the world, people are living longer.
"In 1900, the average life expectancy of a newborn was 32 years. By 2021 this had more than doubled to 71 years."
I will turn 72 next month. All my subsequent lifespan will be beating the odds! Seriously, though: how many years I owe to my successful struggle to quit smoking tobacco 42 years ago, isn't worth the effort to know. Statistically however, it appears to make a big difference in lifespan (e.g. https://evidence.nejm.org/doi/full/10.1056/EVIDoa2300272).
In my first-hand yet irreducibly subjective experience, self-destructive behavior is often successful, and choosing to avoid destroying oneself enables greater individual happiness, health and productivity than the alternative. YMMV, as we said when the Internet was new.
if the analogy has confused you, because you have feelings about smoking based on your own personal experience, that's completely understandable. At any rate, nature does not provide any examples of successful or sustainable outcomes through bureaucratic mandates. The hidden dependencies must always result in unintended consequences. True optimality arises only through immensely complex feedbacks. Nature thrives precisely because it lacks a central planner. At the surface, the carnage and perceived horror in its checks and balances might seem disturbing to us. However, confusion may arise when we think that we can stand apart from it and impose order based on our own value judgements. When we try to solve perceived problems through technocratic, top-down interventions, often framed through the relatively new lens of scientism, we may unintentionally accelerate our own demise. I realize this is a radical perspective. But it’s hard to ignore that it is precisely since the rise of modern science, academia, and its close ties to centralized global governance that nature’s equilibrium has become increasingly disrupted. We now find ourselves chasing and extinguishing the very fires we’ve inadvertently lit, with no end in sight for this spiral.
When you said "if a few smokes provides someone with the joie de vivre", I assumed you were speaking from experience: my bad. Your reply is well-written and thought-provoking. Nonetheless, my comments about self-destructive individual behavior apply to our aggregate welfare as well. Under the mediocrity principle (https://www.edge.org/response-detail/11272), "true optimality" is unattainable, but melioration is often within reach. IOW, "perfect" is the enemy of "less bad".
You presumably know that anthropogenic global warming is a tragedy of the commons: the result of the global "free" market's ancient propensity to socialize as much transaction cost as it can get away with. Because producers and consumers both privately benefit by socializing part of their marginal cost out of the market price, only collective intervention, i.e. "mutual coercion, mutually agreed upon" (G. Hardin) can put a cap on the rising cost of global warming in money and grief, already being paid by involuntary 3rd parties, often out of proportion to their private emissions.
Yet collective intervention aimed at decarbonizing national economies need not be "technocratic" nor centrally controlled. For example, a flat fee per tonne of carbon, taken from producers where it enters the national economy, if well-crafted by Congress (work with me, OK?), would tilt the production of all goods and services toward carbon-neutral alternative energy sources (https://citizensclimatelobby.org/price-on-carbon/). Metaphorically, it would be a nudge to the "invisible hand" of the free market by the "visible hand" of collective intervention. History is replete with successful examples: indeed, the vast profits to the fossil fuel industry today are enhanced by over a century of government intervention on its behalf.
With a corrected price signal for fossil carbon, market forces can build out the carbon-neutral global economy, until emissions reach zero. At that point, all other causes of ecological, economic, and social instability will still be present, but a constantly changing climate won't be one of them anymore. YMMV, but IMO that's less bad than open-ended warming is.
In the USA, the hard part is to persuade enough voters that collective action is necessary, when the only alternative is open-ended global warming and the relentlessly accumulating aggregate cost therefrom. And all we have to do is vote Democratic, as the default US party of collective action for collective benefit!
This seems inconsistent with more nuanced answers that you have given in the past, e.g., https://thebreakthrough.org/issues/energy/howarth-natural-gas . Have you changed your thinking?
Zeke, the hyperlink for "lead to a world a bit below 3C warming" is not working.
Good catch; should be fixed now.
Unfortunately, diamonds and carbon (CO2) are forever and lack of progress now is not helping.
Revolution can't wait, it's now or never.
Depends on what you mean by "revolution". Speaking for myself, my street fighting days are over. My only hope is that enough US voters will realize they made a mistake last November, to at least retake the House in 2026.
"maurice forget" could easily be an AI agent. Or maybe just a Ouija board.
Revolution begins when people open their eyes and realize it can't continue. They must change or disappear.
Go on then, what are you waiting for?
Oceans are made up by individual drops gathering together.
And crystals grow from nucleation sites. Still waiting to hear when you'll bravely stand up for what you believe in and start your revolution
Are we speaking the same language?
Man, metaphors are hard for some people i guess
C'est ça.