I wrote the following as part of a draft paper in mid April:
Global warming progresses apace: Earth’s energy imbalance and global ocean heat content continue to increase
Earth’s energy imbalance reached its highest level, with the planet’s climate system accumulating heat primarily in the oceans. Driven by rising greenhouse gas emissions, the Earth currently retains more solar energy than it radiates back into space, with approximately 90% of this excess heat being absorbed by the global ocean. In 2025, global upper 2000-meter ocean heat content reached its highest level on record, with annual records being broken for nine consecutive years (2017–2025). The changes in clouds represent a strong positive feedback driven by changes in the atmospheric circulation.
Earth’s energy imbalance (EEI) is a fundamental metric of global Earth system change, quantifying the cumulative impact of natural and anthropogenic radiative forcings and feedbacks. Estimates of EEI change are obtained through satellite radiometric observations at the top of the atmosphere (TOA), while the quantification of EEI absolute magnitude is facilitated through heat inventory analysis. Globally, about 90% of heat uptake occurs as an increase in ocean heat content (OHC) (Cheng et al. 2022; Pan et al. 2026a), but there is no direct relationship locally. Suggestions have been made that the EEI heating is accelerating (Merchant et al 2025; Allan and Merchant 2025), along with sea surface temperatures (Foster and Ramstorf 2026) and OHC over the past four decades, but with much less evidence since about 2005 (Pan et al. 2026). Natural variability, including El Niño-Southern Oscillation (ENSO), complicate the climate change signal (Miyamoto et al. 2026) and many studies have not adequately accounted for such effects. Nevertheless, heating increases are occurring but driven mostly by changes in clouds and the atmosphere and ocean circulation (Trenberth et al. 2025; Allan and Merchant 2025; Tselioudis et al. 2025) in ways not fully understood.
Land is warming much faster than the oceans at the surface. In between the EEI at the TOA and the surface is the atmosphere and all the weather dynamics, so that changes in the atmospheric circulation and energy and water transports play a major role in influencing clouds and surface heat and water exchanges (fluxes) and ultimately OHC changes (Trenberth et al. 2025). Changes in atmospheric winds also alter ocean currents which further affect the atmosphere through changes in SSTs. Ocean heat transports are one consequence that contribute to the major differences between EEI and the OHC response, and can be deduced as a residual (Trenberth et al. 2005, Pan et al. 2026b). The latter show that ocean meridional heat transport follows ONI (ENSO) by 4 months, highlighting the role of natural variability also (Merchant et al. 2025; Tsuchida et al. 2026).
Because the ocean stores more than 90% of the excess energy associated with EEI, OHC provides one of the most robust measures of long-term climate change. Global OHC reached a new record high in 2025, marking the ninth consecutive record year, and the mean ocean warming rate increased markedly from pre-2005 values (Pan et al., 2026; Bao et al., 2026). This warming has become increasingly widespread, with about one-third of the global ocean ranking among its historical top three warmest states in 2025. Long-term warming extends from the surface into the deep ocean, although the magnitude of warming varies by depth and region. Strongest OHC warming has occurred in a distinctive zonal pattern near 30 to 45 latitude in both hemispheres (Trenberth et al. 2025). This spatially uneven warming suggests that regional OHC changes are shaped not only by net sea surface heat fluxes, including radiation, but also by oceanic heat transport, which redistributes heat across basins and latitudes and is influenced by climate variability such as ENSO (Pan et al., 2026b).
Global climate change arises from forcings external to the Earth system, and the primary forcing recognized is from human influences on the composition of the atmosphere. Burning of fossil fuels has led to over 50% increase in carbon dioxide in the atmosphere since pre-industrial times, and rates of increase have continued to grow through 2025. Increases in methane and nitrous oxide continue and are also caused by human activities. Changes in pollution (atmospheric aerosols) have complicated direct effects involving heating in some layers from carbonaceous aerosols but more generally cooling such as from increased sulfate particles. Several assessments indicate that effects of aerosol changes are mostly fairly minor. However, indirect effects on clouds are also profound.
As well as direct forcings, there are multiple feedbacks. Radiative cooling is a strong negative feedback. Increases in atmospheric water vapor, another greenhouse gas but short-lived, amplify warming, and a warming atmosphere can hold about 7% more water vapor per C temperature increase, as governed by the Clausius-Clapeyron equation. Loss of snow and ice also provide positive feedbacks through changes in albedo. Changes in clouds and cloud properties, in part from indirect effect of atmospheric aerosols, have been fraught.
Over the past few years, the global average surface temperature has increased more than expected, and in some cases has led to claims of acceleration of global warming (Foster & Rahmstorf 2026). It has been shown in a number of studies that this relates to how clouds have changed (Loeb et al 2025; Mauritsen et al. 2025; Merchant et al. 2025; Ceppi et al. 2026). Key changes include a reduction in overall cloud cover (specifically low-level reflective clouds), clouds moving to higher altitudes, and storm tracks shifting poleward, allowing more sunlight to reach the surface (Tselioudis et al. 2025; Trenberth et al. 2025). This has led to an increase in absorbed solar radiation (ASR), even as outgoing longwave radiation (OLR) has increased in association with higher temperatures.
It is not fully clear how much of the pronounced changes in atmospheric circulation and clouds is a response to forced climate change, as models forced with observed sea surface temperatures have tropical expansion rates that vary widely because of internal atmospheric variability (Miyamoto et al. 2026). Indeed, high temperatures in 2023 and 2024 are associated with a strong El Niño event, and global warming has been associated with jumps to new levels with such events (Trenberth 2015; Tsuchida et al 2026). However, as atmospheric reanalyses and global climate models do not replicate observed clouds and precipitation very well, this attribution remains a very important research question (Landsberg and Barnes 2026; Park and Soden, 2025; Allan and Merchant, 2025…)
Indeed, with human-induced climate change, more water vapor and heating strengthens convection making it taller and narrower, and broadens the subsidence regions in the subtropics and extratropics, thereby opening the “iris” of the planet (Lindzen et al. 2001). This is directly related to the observed changes in atmospheric circulation. Lindzen et al. claimed this was a negative feedback because it permits more radiation from the warmer lower atmosphere and surface to escape to space, and hence OLR would increase. However, fewer clouds also increase absorbed solar radiation (Trenberth & Fasullo 2009; Tselioudis et al. 2025), a factor not accounted for in Lindzen’s analysis, and the net result is a pronounced positive feedback. It remains a challenge for climate models and atmospheric reanalyses to simulate these observed changes.
“Indeed, with human-induced climate change, more water vapor and heating strengthens convection making it taller and narrower, and broadens the subsidence regions in the subtropics and extratropics, thereby opening the “iris” of the planet (Lindzen et al. 2001).” This is really interesting. I’ll admit some of the technical aspects of your response are confusing to me (not because they are unclear, only because I am uninformed) but this seems like a key distinction. Is it an open question as to whether this “iris” will continue allowing for more warming in the future? This seems like the key distinction? If the iris opening is a forced response to warming, wouldn’t it belong in the feedback term, and imply a sensitivity above the AR6 3C central estimate? Or do you read it as a transient pattern effect tied to the recent Pacific configuration, which would leave ECS unchanged? I’m unclear which side of that line you’d put it on, and it seems to determine whether this is an alternative to Hansen’s aerosol story or a different route to a similar conclusion.
The iris effect is not local and can not be readily dealt with from a global or 1D model perspective. Yes, it appears to be a positive feedback and thus would add to climate sensitivity. Not clear yet how much is climate change vs climate variability and good reasons to suspect global models not to do this well as it involves convection, which is parameterized. It may also be transient at least in part. Overall on climate sensitivity, though, I have been convinced by several articles that show that global climate models with high climate sensitivity overestimate the coldness of past paleo climate regimes, at odds with some of Hansen's claims. It put the climate sensitivity close to 3 or a tad above.
«more water vapor and heating strengthens convection making it taller and narrower, and broadens the subsidence regions in the subtropics and extratropics,»
This sounds to me like it might also explain why transitions between weather systems are often more extreme, in both wind speed and precipitation rates, and are particularly problematic as the movement of the systems along the jet streams slow and stall.
In the end, for me , it's record-schmecord. It's somehow entertaining, yes, but the bottom line is: the whole thing is becoming somewhat uncomfortably fast.
Slightly OT: cloud simulation has been the achilles heel of earth models until now - the biggest source of uncertainty. The discussion around lower albedo, faster warming is largely centered around clouds. Better modelling would be invaluable here. So, as a suggestion, I would really love to see a post about AR7 models and progress in cloud simulation.
The climate scientists' arguments about ·global· means (temps, SLR, rain events, whatever) are just someone else's intellectual amusement for people who are suffering in the here and now.
This is one reason I so loathe the scoldings about not being a "doomer" from people who are socio-economically distanced from the worst of what is already happening to hundreds of millions of people.
My friend, I, for one, sympathize with your exasperation and moral indignation, but by your use of 'doomer', you set up a forced choice from a false dichotomy. Our meaningful choice isn't between salvation and doom, but lower and higher cumulative net social cost. Empathy for the victims of anthropogenic global warming to date just means we should strive for lower, not higher!
Dr. Hausfather, Katharine Hayhoe, and Mike Mann, inter alia, have defined climate doomism as the belief that catastrophic climate change is completely unstoppable, that civilizational collapse (or extinction) is inevitable, and that any effort to mitigate or adapt to warming is ultimately futile. I would include in the definition an insistence that only immediate transition to a fully steady-state economy will avert doom. Knowingly or not, doomers abet the Koch network by deterring collective intervention to take the profit out of fossil fuel extraction.
I call out swivel-eyed doomers on pro-climate-science fora who insist they know better than the consensus of trained, mutually disciplined professional climate scientists. I submit it's irrelevant that I am "socio-economically distanced from the worst of what is already happening to hundreds of millions of people." AFAICT, so are you. I, for one, take no amusement, intellectual or otherwise, from scientific disagreements about just how much warming has occurred and how much is yet to occur, exactly where and when. But I maintain it's important to get global metrics right, as they are the scientific evidentiary baseline frontline communities need to demand climate reparations, adaptation funding, and systemic decarbonization.
"Climate doomism is an increasing concern for climate change communication. In the United States, this opinion regarding anthropogenic climate change is now more prevalent than climate skepticism, and is *the primary reason cited for opposition to climate action.* Doomism is the belief that catastrophic warming of the planet is now inevitable, and that effective mitigation is impossible. The behaviors resulting from this view are comparable to the result of climate skepticism: doomism produces paralyzing eco-anxiety and subsequently inaction."
Frankly, I think that's sufficient reason to 'scold' doomers. IMHO, more than enough is known to motivate everyone who isn't a carbon capitalist to act collectively to decarbonize the global economy, with all the alacrity democracy can muster. I'm skeptical that 8.3 billion people will ever agree to live with less stuff, but they just might agree to public investment to drive down the LCOE+ of renewable energy, until nobody wants to burn fossil carbon because RE is cheaper. Doomers aren't helping!
I really like Hansen's approach & delivery of his reasoning; and if I've learned anything about climate, it's that his projections prove quite prescient. I certainly wouldn't bet against anything he forecasts.
Really appreciate your work, this update, and the clarification/distinction between your underlying philosophies. 👍🏻
A connected question is why the El Nlno is so strong, and whether that is connected to a stronger aerosol effect than the IPCC's mean value. We may have to wait for the next El Nino to get a good answer.
... Of course the fact that Hansen might be right (or put otherwise, that the actual aerosol effect may be near the upper end of what the IPCC finds possible) is reason enough for urgent action, just in case.
I'm not a dynamicist but it seems unlikely for there to be a strong link between aerosols (at least the IMO shipping rules) and El Nino, given that their forcing impact is fairly localized and there are few shipping tracks in the ENSO regions. But I'm not too familiar with the literature here!
You hedge. Given what you figure is the probability of disaster, you set aside a proportional amount of money in puts, T-bills or gold according to taste. Well that's a labored analogy, my fault for not starting with a better one. How about this: if experts tell you there's a good chance your house will be caught in a wildfire (although they disagree about how bad it could be), you should pay a substantial amount for fireproofing the roof, clearing flammable brush away from your house, buy a fireproof safe for documents and an insurance policy in case the worst befalls, etc.
It is best if the forecast is right for the right reason.
Hansen is quite wrong in 2 respects: his climate sensitivity and the role of aerosols. Indeed with extensive record wildfires, smoke is all over the place. Moreover, several studies now suggest that Hansen greatly overestimates the role of aerosols. As we have shown, the pattern of change is one where the jet stream and storm tracks have moved polewards over the oceans and so the subsidence in the subtropical high pressures has too. That is what is responsible for the heat domes that keep reforming over Europe and North America: not aerosols. Those give rise to the heat and drying and wildfires. This is part of climate change and related to the convection in the tropics becoming stronger and taller so that the subsidence branch of the Hadley Circulation and monsoons is broader. El Nino developments enhance that pattern.
'Smoke all over the place'? Short lived in the lower troposphere maybe and comprising of soot that increases warming.
Yes, jet streams etc are changing and due to climate change, Hansen agrees. The recent reduction in sulphur aerosols by the Chinese reveals the already present warming in the oceans that seems to be associated with the atmospheric dynamic changes that lead to heat domes over Europe and North America. https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2026GL122424
Dr.Trenberth, if you don’t mind me asking, do you have a personal best ECS estimate? Where do you think the plausible upper bound lies? I am especially confused by the EEI spike of recent years, the possibility the pattern effect might be leading to biased low ECS estimates, and the appearance of some studies that do show quite a high aerosol sensitivity (pre-print linked in footnote 4 of this piece: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2654/)
Has there been work looking at changes in cloud distribution wrt height which wold follow from strengthening convection? I know there is some satellite data looking at coverage changes in space. Shifting the distribution of clouds formed from largely naturally occurring aerosols in space and height always seemed it would have a much greater forcing potential than reduction in human aerosols but in the end it is an argument over magnitudes.
Tselioudis, G., Remillard, J., Jakob, C., & Rossow, W. (2025). Contraction of the world’s storm-cloud zones the primary contributor to the 21st century increase in the Earth’s sunlight absorption. Geophysical Research Letters, 52(11). https://doi.org/10.1029/2025GL114882
I think Hansen would say that changes in the storm-clouds were caused by aerosols in the first place and the present contraction and other changes in clouds in the absence of sulphur aerosols and in the presence of subsequently unmasked GHG warming is leading to the increased warming.
I, amongst many others, would say Hansen is right. Seems he's always right and the daggers come back and say , "Well, he was lucky". Hansen has been right because he practices climate science right✅️
Hansen has been right that global warming is strong but he has generally been wrong on specific events. He testified before Congress and utilized the major US drought in 1988 as evidence but it was more related to La Nina at that time.
Trenberth, K. E., G. W. Branstator and P. A. Arkin, 1988: Origins of the 1988 North American Drought. Science, 242, 1640–1645. DOI: 10.1126/science.242.4886.1640
His information on climate sensitivity is wrong also because if one uses a very high climate sensitivity then the ice ages get much too cold in paleo climate simulations.
He is correct that we do not measure the effects of aerosols well, but the evidence suggests that the effect is not as large as he suggests. However, changes in clouds from dynamics are not included in his reasoning.
But more power to him for raising the issues with politicians who refuse to act adequately.
Thank you for your courteous reply, Kevin. I must admit even Hansen will admit he's not perfect. But, his assessments are generally very 👍. And he correctly makes right calls as the Lone Ranger. Like someone else posted on here, if it were a race or climate dice... I'd put my house on Hansen.
I worry about the water cycle going amuck(amoc too) with the 🥵 . And why the literally he'll aren't we trying to reflect and hydrate now in the tropics.
I, for one, will wait for intersubjective verification of his latest claims. Because "the first principle is you [i.e., me: MA] must not fool yourself -- and you are the easiest person to fool." -R. Feynman.
That is a very important question. I think that there has been a lack of humility on all sides.
To conservatives, the precautionary principle appears to have been swallowed up for government grift during recent Democratic administrations.
Not that Trump's administrations have embraced the precautionary principle either. I hope that it isn't the case, but I can see both of his administrations being golden ages for renewables. In the 2010s, he had a hands-off, federalist perspective that let the states set their own policies. They did, and renewables flourished.
And this time around, climate change may be so undeniable by mid-2028 that action has to be taken.
interesting that you seem to imply it will take till mid 2028 for Global Frying to become undeniable ....or is that just linking to the next US Presidential elections ....and donald being one step closer to a jail cell?
"To conservatives, the precautionary principle appears to have been swallowed up for government grift during recent Democratic administrations. "
Whereas to climate realists, the precautionary principle appears to have been swallowed up by fossil-fuel producer and investor grift of unpriced externalities and structural subsidies over a century ago, and gleefully surrendered altogether by the current plutocratic administration.
"I hope that it isn't the case, but I can see both of his administrations being golden ages for renewables. In the 2010s, he had a hands-off, federalist perspective that let the states set their own policies. They did, and renewables flourished."
That was hardly his doing, but the result of polycentric public investment in the absence of federal attention. Under the Tragedy of the Commons, i.e. common-pool resource economics, the ancient 'free' market would never have begun decarbonizing energy production without collective intervention to limit the climate cost of emissions in some way or another.
State-level collective interventions certainly helped, but the Interstate Commerce Clause of the Constitution makes the federal government the final authority on who gets to control energy markets and how far state authority can reach. And only the federal government can control our borders and negotiate with other nations. The IRA of 2022 is credited with measurably accelerating US decarbonization, already begun by economic downturns and coal-to-gas conversion. It's still helping in spite of Trump's best, spiteful efforts!
In footnote 4, when you say, “I’d personally give a central estimate closer to 3.5C than Hansen’s ~4.5C, as well as a new preprint suggesting forcing from the 2020 IMO low sulfur shipping fuel regulations may end up somewhere between Hansen’s high and my low-end estimate,” are you implying that this new pre-print actually provides evidence that ECS is more modest than Hansen would guess?
I am partially curious because your estimate seems to have gone up—from 3C to 3.5C.
Regressing Berkeley Earth GMST on log₂(CO₂) gives 2.4 K/doubling over 1850–2025 and 2.9 over 1975–2025. Those are transient quantities, measured while the imbalance sits above 1 W/m² — closer to TCR than to ECS, and they can't settle 3.5 vs 4.5 in either direction. What they do show is a slope climbing as the record lengthens, not a static number.
The effects are already serious at 1.44 °C global, 2.03 °C over land in Berkeley's 2025 report — a fraction of the warming these pathways deliver, and a vanishingly small fraction of the duration.
Which is the part I think gets lost. The assessed sensitivity is effectively a 150-year quantity — Sherwood et al.'s S — with ice sheets and vegetation treated as forcings rather than feedbacks. It doesn't set how long the excess carbon stays, and residence time is what sets the length of the excursion: tens of millennia, and not a term in the sensitivity debate at all.
Sink weakening is in there. You can see it in the AR6 airborne fraction, which climbs from about 30% in the lowest scenario to 62% in the highest, precisely because higher emissions saturate the land and ocean sinks.
What's largely missing is permafrost carbon and forest dieback. And there's a structural piece: CMIP6 was concentration-driven, so the Earth system models' carbon cycles weren't fully engaged. CMIP7 goes emission-driven, which brings those feedbacks in and is expected to widen the concentration range.
My own loop is simpler still — a fixed sink kernel with no temperature dependence at all. So if you're right, every one of those omissions runs the same direction: more carbon staying, longer.
This is interesting. It seems wildfires and explosions produce particulates that only reach the surface level or lower troposphere and gravity and rain pull them back out within weeks. Exceptionally intense wildfires reach the stratosphere and can linger longer up to a year. Sulphur from volcanoes or shipping oil reaches the stratosphere and can linger for 1 to 3 years. It would seem the loss of aerosols from shipping is not compensated for by increasing wildfire and war, which are also over the land not ocean where most of the warming and loss of cloud cover is occurring.
Dark aerosols like black carbon, ie soot, actually absorb heat and reduce reflection thereby warming the atmosphere.
‘Soot is made of dark particles of carbon from burning fossil fuels, wood, or other plant matter. These dark particles absorb sunlight and warm the atmosphere. Soot leads to additional warming when it settles onto snow and ice because it makes the surface darker, which causes faster melting.
Wildfires, cooking fires, industrial activities, and diesel engines are made of soot. Reducing soot emissions would have a quick cooling effect on the atmosphere, which would bring the added benefit of improving human health.’
So double whammy- warming from loss of sulphur aerosols and warming from increase of wildfires and war.
I've taken to distinguishing "lung pollution" or "ecosystem pollution" from "warming pollution" (GHGs and albedo-lowering effects). As an old, I'm used to associating the bare word "pollution" with nasties that directly affect the health of ourselves and our surrounding ecosystems.
For example, China has been doing a stunning job of reducing ecosystem pollution, while effectively hold their domestic status quo in warming pollution. (Though they are providing the rest of the world with tech to reduce their own countries' ability to avoid creating more warming pollution.)
A while back Jason Box & co.'s Dark Snow Project was researching the albedo-changing effects of wildfire soot that reaches Greenland. (They instead found that a lot of the darker albedo was not just from meltwater but from ·algae· being fed by particulates. That raised the question for me: How did the algae get onto the Greenland icecap in the first place?)
I’ve seen some discussion of this El Niño possibly causing a land temp of 3C. With how strong this El Niño is being forecasted to be, do you think that’s a possibility? (Also the fading old nag line feels kinda mean.)
I wonder when deniers will tell us how. much warming they want, and what level of calamity they’re willing to tolerate before they decide “the science is settled” enough to actually start taking responsibility, and doing something about it.
Zeke, either way, 2026 is going to be a climate disaster. The Great Plains and Western US are enduring severe drought and extreme heat. We see long, expanding heatwaves out West and record summer rainfall in parts of the East. Crop losses are expected to be rampant. Farm income is projected to be cut by 24% this year. In Europe, record-breaking heatwaves and drought have destroyed nearly 10 million tons of grain, causing over $2.3 billion in losses. Fire is laying waste to much of the West, Canada, and Europe. Last check, Canada had over 900 active fires. When I posted that fact on Facebook, the lunatics claimed they must have been started intentionally. (We're talking largely about remote forests.) And of course there is the rest of the world...
Oh but I don't believe in climate change! It's all a big liberal hoax! Coal is clean! (Snark, of course).
The "attributable casualties" should be itemized on a website that shows just about every person, biotic and thing harmed/killed/destroyed daily AND what the predictable casualties that will happen.
All of us, collectively, through voluntary and governmental actions. Some always has to pay. Better pay for mitigation now before we lose our biosphere.
The “0.02C above vs 0.05C below” gap deciding record vs second-warmest is wild, hundredths of a degree, and headlines in january will call it certainty either way. also respect the plain concession halfway through, rare to see in forecasting debates. But the real point here is a single warm year can’t tell you if it’s high sensitivity + aerosols or just trend + a strong El Niño. same lesson as my whole beat — one data point isn’t an answer, it’s a data point.
There is much going on that is not fully clear.
I wrote the following as part of a draft paper in mid April:
Global warming progresses apace: Earth’s energy imbalance and global ocean heat content continue to increase
Earth’s energy imbalance reached its highest level, with the planet’s climate system accumulating heat primarily in the oceans. Driven by rising greenhouse gas emissions, the Earth currently retains more solar energy than it radiates back into space, with approximately 90% of this excess heat being absorbed by the global ocean. In 2025, global upper 2000-meter ocean heat content reached its highest level on record, with annual records being broken for nine consecutive years (2017–2025). The changes in clouds represent a strong positive feedback driven by changes in the atmospheric circulation.
Earth’s energy imbalance (EEI) is a fundamental metric of global Earth system change, quantifying the cumulative impact of natural and anthropogenic radiative forcings and feedbacks. Estimates of EEI change are obtained through satellite radiometric observations at the top of the atmosphere (TOA), while the quantification of EEI absolute magnitude is facilitated through heat inventory analysis. Globally, about 90% of heat uptake occurs as an increase in ocean heat content (OHC) (Cheng et al. 2022; Pan et al. 2026a), but there is no direct relationship locally. Suggestions have been made that the EEI heating is accelerating (Merchant et al 2025; Allan and Merchant 2025), along with sea surface temperatures (Foster and Ramstorf 2026) and OHC over the past four decades, but with much less evidence since about 2005 (Pan et al. 2026). Natural variability, including El Niño-Southern Oscillation (ENSO), complicate the climate change signal (Miyamoto et al. 2026) and many studies have not adequately accounted for such effects. Nevertheless, heating increases are occurring but driven mostly by changes in clouds and the atmosphere and ocean circulation (Trenberth et al. 2025; Allan and Merchant 2025; Tselioudis et al. 2025) in ways not fully understood.
Land is warming much faster than the oceans at the surface. In between the EEI at the TOA and the surface is the atmosphere and all the weather dynamics, so that changes in the atmospheric circulation and energy and water transports play a major role in influencing clouds and surface heat and water exchanges (fluxes) and ultimately OHC changes (Trenberth et al. 2025). Changes in atmospheric winds also alter ocean currents which further affect the atmosphere through changes in SSTs. Ocean heat transports are one consequence that contribute to the major differences between EEI and the OHC response, and can be deduced as a residual (Trenberth et al. 2005, Pan et al. 2026b). The latter show that ocean meridional heat transport follows ONI (ENSO) by 4 months, highlighting the role of natural variability also (Merchant et al. 2025; Tsuchida et al. 2026).
Because the ocean stores more than 90% of the excess energy associated with EEI, OHC provides one of the most robust measures of long-term climate change. Global OHC reached a new record high in 2025, marking the ninth consecutive record year, and the mean ocean warming rate increased markedly from pre-2005 values (Pan et al., 2026; Bao et al., 2026). This warming has become increasingly widespread, with about one-third of the global ocean ranking among its historical top three warmest states in 2025. Long-term warming extends from the surface into the deep ocean, although the magnitude of warming varies by depth and region. Strongest OHC warming has occurred in a distinctive zonal pattern near 30 to 45 latitude in both hemispheres (Trenberth et al. 2025). This spatially uneven warming suggests that regional OHC changes are shaped not only by net sea surface heat fluxes, including radiation, but also by oceanic heat transport, which redistributes heat across basins and latitudes and is influenced by climate variability such as ENSO (Pan et al., 2026b).
Global climate change arises from forcings external to the Earth system, and the primary forcing recognized is from human influences on the composition of the atmosphere. Burning of fossil fuels has led to over 50% increase in carbon dioxide in the atmosphere since pre-industrial times, and rates of increase have continued to grow through 2025. Increases in methane and nitrous oxide continue and are also caused by human activities. Changes in pollution (atmospheric aerosols) have complicated direct effects involving heating in some layers from carbonaceous aerosols but more generally cooling such as from increased sulfate particles. Several assessments indicate that effects of aerosol changes are mostly fairly minor. However, indirect effects on clouds are also profound.
As well as direct forcings, there are multiple feedbacks. Radiative cooling is a strong negative feedback. Increases in atmospheric water vapor, another greenhouse gas but short-lived, amplify warming, and a warming atmosphere can hold about 7% more water vapor per C temperature increase, as governed by the Clausius-Clapeyron equation. Loss of snow and ice also provide positive feedbacks through changes in albedo. Changes in clouds and cloud properties, in part from indirect effect of atmospheric aerosols, have been fraught.
Over the past few years, the global average surface temperature has increased more than expected, and in some cases has led to claims of acceleration of global warming (Foster & Rahmstorf 2026). It has been shown in a number of studies that this relates to how clouds have changed (Loeb et al 2025; Mauritsen et al. 2025; Merchant et al. 2025; Ceppi et al. 2026). Key changes include a reduction in overall cloud cover (specifically low-level reflective clouds), clouds moving to higher altitudes, and storm tracks shifting poleward, allowing more sunlight to reach the surface (Tselioudis et al. 2025; Trenberth et al. 2025). This has led to an increase in absorbed solar radiation (ASR), even as outgoing longwave radiation (OLR) has increased in association with higher temperatures.
It is not fully clear how much of the pronounced changes in atmospheric circulation and clouds is a response to forced climate change, as models forced with observed sea surface temperatures have tropical expansion rates that vary widely because of internal atmospheric variability (Miyamoto et al. 2026). Indeed, high temperatures in 2023 and 2024 are associated with a strong El Niño event, and global warming has been associated with jumps to new levels with such events (Trenberth 2015; Tsuchida et al 2026). However, as atmospheric reanalyses and global climate models do not replicate observed clouds and precipitation very well, this attribution remains a very important research question (Landsberg and Barnes 2026; Park and Soden, 2025; Allan and Merchant, 2025…)
Indeed, with human-induced climate change, more water vapor and heating strengthens convection making it taller and narrower, and broadens the subsidence regions in the subtropics and extratropics, thereby opening the “iris” of the planet (Lindzen et al. 2001). This is directly related to the observed changes in atmospheric circulation. Lindzen et al. claimed this was a negative feedback because it permits more radiation from the warmer lower atmosphere and surface to escape to space, and hence OLR would increase. However, fewer clouds also increase absorbed solar radiation (Trenberth & Fasullo 2009; Tselioudis et al. 2025), a factor not accounted for in Lindzen’s analysis, and the net result is a pronounced positive feedback. It remains a challenge for climate models and atmospheric reanalyses to simulate these observed changes.
“Indeed, with human-induced climate change, more water vapor and heating strengthens convection making it taller and narrower, and broadens the subsidence regions in the subtropics and extratropics, thereby opening the “iris” of the planet (Lindzen et al. 2001).” This is really interesting. I’ll admit some of the technical aspects of your response are confusing to me (not because they are unclear, only because I am uninformed) but this seems like a key distinction. Is it an open question as to whether this “iris” will continue allowing for more warming in the future? This seems like the key distinction? If the iris opening is a forced response to warming, wouldn’t it belong in the feedback term, and imply a sensitivity above the AR6 3C central estimate? Or do you read it as a transient pattern effect tied to the recent Pacific configuration, which would leave ECS unchanged? I’m unclear which side of that line you’d put it on, and it seems to determine whether this is an alternative to Hansen’s aerosol story or a different route to a similar conclusion.
The iris effect is not local and can not be readily dealt with from a global or 1D model perspective. Yes, it appears to be a positive feedback and thus would add to climate sensitivity. Not clear yet how much is climate change vs climate variability and good reasons to suspect global models not to do this well as it involves convection, which is parameterized. It may also be transient at least in part. Overall on climate sensitivity, though, I have been convinced by several articles that show that global climate models with high climate sensitivity overestimate the coldness of past paleo climate regimes, at odds with some of Hansen's claims. It put the climate sensitivity close to 3 or a tad above.
This is very helpful thanks. Along with Dean Rovang’s recent Substack (https://justdean.substack.com/p/climate-sensitivity-the-most-contestable?publication_id=3946078&post_id=209773674&isFreemail=true&r=3qq3i&triedRedirect=true). I am now a little less concerned that ECS is going to end up being above 4C. I am especially glad to know that none of the newer aerosol studies (like the one cited in footnote 4 of this piece) has swayed you off of that 3C estimate.
«more water vapor and heating strengthens convection making it taller and narrower, and broadens the subsidence regions in the subtropics and extratropics,»
This sounds to me like it might also explain why transitions between weather systems are often more extreme, in both wind speed and precipitation rates, and are particularly problematic as the movement of the systems along the jet streams slow and stall.
FWIW, I'm very interested in Archival Aardvark's questions as well, Dr. Trenberth.
I responded directly
In the end, for me , it's record-schmecord. It's somehow entertaining, yes, but the bottom line is: the whole thing is becoming somewhat uncomfortably fast.
Slightly OT: cloud simulation has been the achilles heel of earth models until now - the biggest source of uncertainty. The discussion around lower albedo, faster warming is largely centered around clouds. Better modelling would be invaluable here. So, as a suggestion, I would really love to see a post about AR7 models and progress in cloud simulation.
These little tussles amuse us at the end of times.
I'm sure the French and Spaniards are paying close attention to this contest.
? to see how devastatingly unprepared they are or how devastatingly unprepared they are?
The climate scientists' arguments about ·global· means (temps, SLR, rain events, whatever) are just someone else's intellectual amusement for people who are suffering in the here and now.
This is one reason I so loathe the scoldings about not being a "doomer" from people who are socio-economically distanced from the worst of what is already happening to hundreds of millions of people.
My friend, I, for one, sympathize with your exasperation and moral indignation, but by your use of 'doomer', you set up a forced choice from a false dichotomy. Our meaningful choice isn't between salvation and doom, but lower and higher cumulative net social cost. Empathy for the victims of anthropogenic global warming to date just means we should strive for lower, not higher!
Dr. Hausfather, Katharine Hayhoe, and Mike Mann, inter alia, have defined climate doomism as the belief that catastrophic climate change is completely unstoppable, that civilizational collapse (or extinction) is inevitable, and that any effort to mitigate or adapt to warming is ultimately futile. I would include in the definition an insistence that only immediate transition to a fully steady-state economy will avert doom. Knowingly or not, doomers abet the Koch network by deterring collective intervention to take the profit out of fossil fuel extraction.
I call out swivel-eyed doomers on pro-climate-science fora who insist they know better than the consensus of trained, mutually disciplined professional climate scientists. I submit it's irrelevant that I am "socio-economically distanced from the worst of what is already happening to hundreds of millions of people." AFAICT, so are you. I, for one, take no amusement, intellectual or otherwise, from scientific disagreements about just how much warming has occurred and how much is yet to occur, exactly where and when. But I maintain it's important to get global metrics right, as they are the scientific evidentiary baseline frontline communities need to demand climate reparations, adaptation funding, and systemic decarbonization.
I refer you to scholarly research on doomism: "Navigating the climate change minefield: the influence of metaphor on climate doomism" (https://www.frontiersin.org/journals/communication/articles/10.3389/fcomm.2024.1380092/full). From the abstract (my emphasis):
"Climate doomism is an increasing concern for climate change communication. In the United States, this opinion regarding anthropogenic climate change is now more prevalent than climate skepticism, and is *the primary reason cited for opposition to climate action.* Doomism is the belief that catastrophic warming of the planet is now inevitable, and that effective mitigation is impossible. The behaviors resulting from this view are comparable to the result of climate skepticism: doomism produces paralyzing eco-anxiety and subsequently inaction."
Frankly, I think that's sufficient reason to 'scold' doomers. IMHO, more than enough is known to motivate everyone who isn't a carbon capitalist to act collectively to decarbonize the global economy, with all the alacrity democracy can muster. I'm skeptical that 8.3 billion people will ever agree to live with less stuff, but they just might agree to public investment to drive down the LCOE+ of renewable energy, until nobody wants to burn fossil carbon because RE is cheaper. Doomers aren't helping!
Big fan of both of you.
I really like Hansen's approach & delivery of his reasoning; and if I've learned anything about climate, it's that his projections prove quite prescient. I certainly wouldn't bet against anything he forecasts.
Really appreciate your work, this update, and the clarification/distinction between your underlying philosophies. 👍🏻
A connected question is why the El Nlno is so strong, and whether that is connected to a stronger aerosol effect than the IPCC's mean value. We may have to wait for the next El Nino to get a good answer.
... Of course the fact that Hansen might be right (or put otherwise, that the actual aerosol effect may be near the upper end of what the IPCC finds possible) is reason enough for urgent action, just in case.
I'm not a dynamicist but it seems unlikely for there to be a strong link between aerosols (at least the IMO shipping rules) and El Nino, given that their forcing impact is fairly localized and there are few shipping tracks in the ENSO regions. But I'm not too familiar with the literature here!
We probably need to wait for the next 10-20 El Ninos to get a better answer.
So, the possibility that Hansen might be wrong would be a reason enough to avoid urgent action? Or were you being sarcastic?
Sorry if I was misunderstood. What I meant was that if a guy says your house is on fire and there is a fair chance he is right, you need to act.
If a guy on X says the market correction is coming, will you sell all your holdings right away. What if many guys say so?
What if many other guys say it's nonsense?
You hedge. Given what you figure is the probability of disaster, you set aside a proportional amount of money in puts, T-bills or gold according to taste. Well that's a labored analogy, my fault for not starting with a better one. How about this: if experts tell you there's a good chance your house will be caught in a wildfire (although they disagree about how bad it could be), you should pay a substantial amount for fireproofing the roof, clearing flammable brush away from your house, buy a fireproof safe for documents and an insurance policy in case the worst befalls, etc.
Also, the big house, 🌎 is in 🔥. Oikos is house in Gr. and eco is our corruption of the root.
Houses on 🔥 wildfires 🔥 water depletion
We gotta reflect andbhydrate
and hydrate
Desal Baby!
All our houses are on 🔥
It is best if the forecast is right for the right reason.
Hansen is quite wrong in 2 respects: his climate sensitivity and the role of aerosols. Indeed with extensive record wildfires, smoke is all over the place. Moreover, several studies now suggest that Hansen greatly overestimates the role of aerosols. As we have shown, the pattern of change is one where the jet stream and storm tracks have moved polewards over the oceans and so the subsidence in the subtropical high pressures has too. That is what is responsible for the heat domes that keep reforming over Europe and North America: not aerosols. Those give rise to the heat and drying and wildfires. This is part of climate change and related to the convection in the tropics becoming stronger and taller so that the subsidence branch of the Hadley Circulation and monsoons is broader. El Nino developments enhance that pattern.
'Smoke all over the place'? Short lived in the lower troposphere maybe and comprising of soot that increases warming.
Yes, jet streams etc are changing and due to climate change, Hansen agrees. The recent reduction in sulphur aerosols by the Chinese reveals the already present warming in the oceans that seems to be associated with the atmospheric dynamic changes that lead to heat domes over Europe and North America. https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2026GL122424
Dr.Trenberth, if you don’t mind me asking, do you have a personal best ECS estimate? Where do you think the plausible upper bound lies? I am especially confused by the EEI spike of recent years, the possibility the pattern effect might be leading to biased low ECS estimates, and the appearance of some studies that do show quite a high aerosol sensitivity (pre-print linked in footnote 4 of this piece: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2654/)
Hmm
I tried to reply but it was too long and the text without references is below
Has there been work looking at changes in cloud distribution wrt height which wold follow from strengthening convection? I know there is some satellite data looking at coverage changes in space. Shifting the distribution of clouds formed from largely naturally occurring aerosols in space and height always seemed it would have a much greater forcing potential than reduction in human aerosols but in the end it is an argument over magnitudes.
Tselioudis, G., Remillard, J., Jakob, C., & Rossow, W. (2025). Contraction of the world’s storm-cloud zones the primary contributor to the 21st century increase in the Earth’s sunlight absorption. Geophysical Research Letters, 52(11). https://doi.org/10.1029/2025GL114882
I think Hansen would say that changes in the storm-clouds were caused by aerosols in the first place and the present contraction and other changes in clouds in the absence of sulphur aerosols and in the presence of subsequently unmasked GHG warming is leading to the increased warming.
Um..no. Europes proximity to the Artic is the driver.
I, amongst many others, would say Hansen is right. Seems he's always right and the daggers come back and say , "Well, he was lucky". Hansen has been right because he practices climate science right✅️
But, I respect your opinion 😁
Hansen has been right that global warming is strong but he has generally been wrong on specific events. He testified before Congress and utilized the major US drought in 1988 as evidence but it was more related to La Nina at that time.
Trenberth, K. E., G. W. Branstator and P. A. Arkin, 1988: Origins of the 1988 North American Drought. Science, 242, 1640–1645. DOI: 10.1126/science.242.4886.1640
His information on climate sensitivity is wrong also because if one uses a very high climate sensitivity then the ice ages get much too cold in paleo climate simulations.
He is correct that we do not measure the effects of aerosols well, but the evidence suggests that the effect is not as large as he suggests. However, changes in clouds from dynamics are not included in his reasoning.
But more power to him for raising the issues with politicians who refuse to act adequately.
Thank you for your courteous reply, Kevin. I must admit even Hansen will admit he's not perfect. But, his assessments are generally very 👍. And he correctly makes right calls as the Lone Ranger. Like someone else posted on here, if it were a race or climate dice... I'd put my house on Hansen.
I worry about the water cycle going amuck(amoc too) with the 🥵 . And why the literally he'll aren't we trying to reflect and hydrate now in the tropics.
I truly respect your work. 😀
"Like someone else posted on here, if it were a race or climate dice... I'd put my house on Hansen."
You can actually do that, you know: https://polymarket.com/event/where-will-2026-rank-among-the-hottest-years-on-record/
I, for one, will wait for intersubjective verification of his latest claims. Because "the first principle is you [i.e., me: MA] must not fool yourself -- and you are the easiest person to fool." -R. Feynman.
Having listened to James for decades it’s clear that he is amongst those who have most accurately warned us of our stupidity.
I expect he’ll be proven right again.
What a sad “victory”.
Bickering scientists while prognosis is existential for most of humanity now.
What happened to the precautionary principle and humility in the light of all our ignorance?
That is a very important question. I think that there has been a lack of humility on all sides.
To conservatives, the precautionary principle appears to have been swallowed up for government grift during recent Democratic administrations.
Not that Trump's administrations have embraced the precautionary principle either. I hope that it isn't the case, but I can see both of his administrations being golden ages for renewables. In the 2010s, he had a hands-off, federalist perspective that let the states set their own policies. They did, and renewables flourished.
And this time around, climate change may be so undeniable by mid-2028 that action has to be taken.
interesting that you seem to imply it will take till mid 2028 for Global Frying to become undeniable ....or is that just linking to the next US Presidential elections ....and donald being one step closer to a jail cell?
Our host says 2027 will be the hottest year ever. I am leaving n some time for it to really sink in. And a bunch of things to break.
Despite some pushback on your previous comment, I like this one a lot!
Trump shut down renewable projects. How does that produce a “golden age”?
"To conservatives, the precautionary principle appears to have been swallowed up for government grift during recent Democratic administrations. "
Whereas to climate realists, the precautionary principle appears to have been swallowed up by fossil-fuel producer and investor grift of unpriced externalities and structural subsidies over a century ago, and gleefully surrendered altogether by the current plutocratic administration.
"I hope that it isn't the case, but I can see both of his administrations being golden ages for renewables. In the 2010s, he had a hands-off, federalist perspective that let the states set their own policies. They did, and renewables flourished."
That was hardly his doing, but the result of polycentric public investment in the absence of federal attention. Under the Tragedy of the Commons, i.e. common-pool resource economics, the ancient 'free' market would never have begun decarbonizing energy production without collective intervention to limit the climate cost of emissions in some way or another.
State-level collective interventions certainly helped, but the Interstate Commerce Clause of the Constitution makes the federal government the final authority on who gets to control energy markets and how far state authority can reach. And only the federal government can control our borders and negotiate with other nations. The IRA of 2022 is credited with measurably accelerating US decarbonization, already begun by economic downturns and coal-to-gas conversion. It's still helping in spite of Trump's best, spiteful efforts!
Murphy's Law is climate science law numero uno 😀
Taking all the fun outta "Itoljuso"
Informative as always.
In footnote 4, when you say, “I’d personally give a central estimate closer to 3.5C than Hansen’s ~4.5C, as well as a new preprint suggesting forcing from the 2020 IMO low sulfur shipping fuel regulations may end up somewhere between Hansen’s high and my low-end estimate,” are you implying that this new pre-print actually provides evidence that ECS is more modest than Hansen would guess?
I am partially curious because your estimate seems to have gone up—from 3C to 3.5C.
Directionally, that is not reassuring.
The IMO forcing is only an indirect indicator of ECS; the EEI work I link to is a stronger line of evidence.
Yes, that makes sense. I assume you linked that IMO study because it provides some that Hansen’s higher-end aerosol forcing estimates might be plausible? It’s nerve-wracking but I did enjoy this Economist breakdown of the whole EEI issue recently: https://www.economist.com/science-and-technology/2026/07/15/the-rate-at-which-earth-is-absorbing-energy-is-alarming-scientists
I am curious as to what evidence will come out around 2028 that will hopefully settle the issue…
Also found that piece interesting it but didn’t see any chatter about it on X. Maybe it happened on BS.
I noticed this as well about ZH’s ECS estimate. I remember hearing 3 a number of years ago. Interesting that you’ve come a bit closer to Hansen.
Regressing Berkeley Earth GMST on log₂(CO₂) gives 2.4 K/doubling over 1850–2025 and 2.9 over 1975–2025. Those are transient quantities, measured while the imbalance sits above 1 W/m² — closer to TCR than to ECS, and they can't settle 3.5 vs 4.5 in either direction. What they do show is a slope climbing as the record lengthens, not a static number.
The effects are already serious at 1.44 °C global, 2.03 °C over land in Berkeley's 2025 report — a fraction of the warming these pathways deliver, and a vanishingly small fraction of the duration.
Which is the part I think gets lost. The assessed sensitivity is effectively a 150-year quantity — Sherwood et al.'s S — with ice sheets and vegetation treated as forcings rather than feedbacks. It doesn't set how long the excess carbon stays, and residence time is what sets the length of the excursion: tens of millennia, and not a term in the sensitivity debate at all.
Dean, how well understood in the modeling is the rapid loss of carbon sinks? I fear they might underlay them in the algorithms
Partly, is the honest answer.
Sink weakening is in there. You can see it in the AR6 airborne fraction, which climbs from about 30% in the lowest scenario to 62% in the highest, precisely because higher emissions saturate the land and ocean sinks.
What's largely missing is permafrost carbon and forest dieback. And there's a structural piece: CMIP6 was concentration-driven, so the Earth system models' carbon cycles weren't fully engaged. CMIP7 goes emission-driven, which brings those feedbacks in and is expected to widen the concentration range.
My own loop is simpler still — a fixed sink kernel with no temperature dependence at all. So if you're right, every one of those omissions runs the same direction: more carbon staying, longer.
Factoring in the permafrost melt, forest die back, water bankruptcies I would think they'd rename the next CMIP to SCARY1 😱
Thanks for your great fast reply!
"a large forcing boost from falling aerosols"
----
Are the massive wildfires and the wars making a significant difference in aerosols?
This is interesting. It seems wildfires and explosions produce particulates that only reach the surface level or lower troposphere and gravity and rain pull them back out within weeks. Exceptionally intense wildfires reach the stratosphere and can linger longer up to a year. Sulphur from volcanoes or shipping oil reaches the stratosphere and can linger for 1 to 3 years. It would seem the loss of aerosols from shipping is not compensated for by increasing wildfire and war, which are also over the land not ocean where most of the warming and loss of cloud cover is occurring.
Dark aerosols like black carbon, ie soot, actually absorb heat and reduce reflection thereby warming the atmosphere.
‘Soot is made of dark particles of carbon from burning fossil fuels, wood, or other plant matter. These dark particles absorb sunlight and warm the atmosphere. Soot leads to additional warming when it settles onto snow and ice because it makes the surface darker, which causes faster melting.
Wildfires, cooking fires, industrial activities, and diesel engines are made of soot. Reducing soot emissions would have a quick cooling effect on the atmosphere, which would bring the added benefit of improving human health.’
So double whammy- warming from loss of sulphur aerosols and warming from increase of wildfires and war.
I've taken to distinguishing "lung pollution" or "ecosystem pollution" from "warming pollution" (GHGs and albedo-lowering effects). As an old, I'm used to associating the bare word "pollution" with nasties that directly affect the health of ourselves and our surrounding ecosystems.
For example, China has been doing a stunning job of reducing ecosystem pollution, while effectively hold their domestic status quo in warming pollution. (Though they are providing the rest of the world with tech to reduce their own countries' ability to avoid creating more warming pollution.)
A while back Jason Box & co.'s Dark Snow Project was researching the albedo-changing effects of wildfire soot that reaches Greenland. (They instead found that a lot of the darker albedo was not just from meltwater but from ·algae· being fed by particulates. That raised the question for me: How did the algae get onto the Greenland icecap in the first place?)
I’ve seen some discussion of this El Niño possibly causing a land temp of 3C. With how strong this El Niño is being forecasted to be, do you think that’s a possibility? (Also the fading old nag line feels kinda mean.)
I wonder when deniers will tell us how. much warming they want, and what level of calamity they’re willing to tolerate before they decide “the science is settled” enough to actually start taking responsibility, and doing something about it.
They refuse to tell us.
Zeke, either way, 2026 is going to be a climate disaster. The Great Plains and Western US are enduring severe drought and extreme heat. We see long, expanding heatwaves out West and record summer rainfall in parts of the East. Crop losses are expected to be rampant. Farm income is projected to be cut by 24% this year. In Europe, record-breaking heatwaves and drought have destroyed nearly 10 million tons of grain, causing over $2.3 billion in losses. Fire is laying waste to much of the West, Canada, and Europe. Last check, Canada had over 900 active fires. When I posted that fact on Facebook, the lunatics claimed they must have been started intentionally. (We're talking largely about remote forests.) And of course there is the rest of the world...
Oh but I don't believe in climate change! It's all a big liberal hoax! Coal is clean! (Snark, of course).
"Zeke, either way, 2026 is going to be a climate disaster."
Yep, it sure looks that way. It will be interesting to see how the attributable casualties (dollars and deaths) stack up by year's end.
The "attributable casualties" should be itemized on a website that shows just about every person, biotic and thing harmed/killed/destroyed daily AND what the predictable casualties that will happen.
That sounds like a job for AI ;^D!
If a doomer is a denier of the possibility of effective mitigation results then a doomer should at least go full throttle on arriving adaptation ASAP.
I do hope downers see a light in mitigation. It would help the cause.
Who’s gonna pay for all that “mitigation”?
All of us, collectively, through voluntary and governmental actions. Some always has to pay. Better pay for mitigation now before we lose our biosphere.
Except governments don't want to commit to doing it. Canada's government back-tracked completely.
Carney did a 180.
Exactomundo. It's all f'd up. There is no real global heating mitigation directive. Seems like too many wealthy vested interests block progress
The prediction market says we’re f*cked either way 🔥
💯 we gotta kickass on climate restoration yesterday
The “0.02C above vs 0.05C below” gap deciding record vs second-warmest is wild, hundredths of a degree, and headlines in january will call it certainty either way. also respect the plain concession halfway through, rare to see in forecasting debates. But the real point here is a single warm year can’t tell you if it’s high sensitivity + aerosols or just trend + a strong El Niño. same lesson as my whole beat — one data point isn’t an answer, it’s a data point.