Last month I wrote the following post. I scheduled it for November, but then some Scientific American-related news arose, so I’m bumping it up in the schedule.
First, here’s my post from May:
I’m not saying this is the same Scientific American as old. Martin Gardner is long gone, and in the age of social media the articles are shorter. That’s the way of the world. But it’s got serious, interesting articles, a mix of pure science, applied science, policy, and service journalism. The latest in science without the boosterism of so much of science and technology reporting.
Last year, though, the magazine was much more political:
A bit of policy is fine, and there’s a lot of science to global warming, for sure. I wouldn’t want Scientific American to “bothsides” the issue. I’m not saying they need entirely to stick to sports, as it were. But the politicking was getting out of control. I’m glad they’ve returned to their lane.
Then the other day this happened:
Scientific American has been acquired by LabX Media Group, which holds Discover Magazine, IFLScience, and a number of other science publications. . . . And they have started out by firing writers and editors. . . .
I know nothing about LabX Media Group or the new Scientific American management, so I have no sense of whether this is a mere budget-cutting realignment or a full-on Sports Illustrated-style bust-out operation. Martin Gardner is a culture hero and deservedly so, but that was a long time ago, and those days aren’t coming back. Indeed, blogs like these, many of which are Gardner-inspired in one way or another, have taken his place.
It’s funny how magazines, even online, keep disappearing. The model of paying a magazine $50 a year for a subscription and getting a range of interesting material, seems more reasonable than paying $50 each for subscriptions for a bunch of individual bloggers, but, with the exception of the New Yorker, the New York Times, and a few others, we don’t really see much of that.
One way to see this is that I’m not myself a Scientific American reader. I follow all these blogs, many of which are science themed, and each of which, in its own way, goes into more depth than I’d get from a Scientific American article. So there’s this weird thing where I’m concerned about something that I’m not reading anyway. Which is different from Sports Illustrated. Back when Sports Illustrated was a real thing, I’d buy it from time to time. I read it for the articles, as the saying goes.
That said, institutions continue in their own way. I was happy recently to see that Scientific American had pulled itself out of its politicized rut, so it’s a disappointment if it’s now getting taken apart.
In the face of things like Trump calling climate change a hoax, or OMB’s plan to put political appointees in charge of funding decisions, how can a scientific publication not get political?
John:
I agree that science and politics overlap, and I wouldn’t want a science magazine to steer away from political topics. But I think the Scientific American of a year ago was going too far, with news items like Trump Aims to Cut Program Used to Help Hospitals Evacuate during Disasters.
Why is reporting facts “going too far” for a science magazine? Or do you dispute the factuality of any of these articles?
This absurd remark highlights much of what is wrong with the American intellectual elites in the face of an Orwellian propaganda machine that they not only are unable but also unwilling to face.
Piglet:
My problem is not that they’re reporting facts; my problem is that “Trump Aims to Cut Program Used to Help Hospitals Evacuate during Disasters” isn’t really about science. It shouldn’t be a Scientific American article, any more than they should be running an article about Trump ruining the World Cup or Chris Christie ruining the traffic flow of the George Washington Bridge or whatever.
I mean, sure, it’s their magazine and they can do whatever they want. I just think that this sort of straight-up politicking doesn’t fit their traditional mission. That sort of article would fit just fine in a political or policy magazine such as the New Republic or the Washington Monthly.
Ok I see your point – they should focus more narrowly on scientific topics. That shouldn’t preclude political topics if they are closely related to science.
AI assisted evaluation of that story of cuts to Hospital Disaster Funds:
[Rest of comment cut. Recall our chatbot policy. Just post the prompt. — AG]
Andrew: That’s an interesting example of what you consider to be “going too far”. Surely you’re aware of, umm, let me put it as, certain cultural controversies …
“The model of paying a magazine $50 a year for a subscription and getting a range of interesting material, seems more reasonable than paying $50 each for subscriptions for a bunch of individual bloggers, but, with the exception of the New Yorker, the New York Times, and a few others, we don’t really see much of that.”
For a long, long time, I’ve wondered why the business models of “traditional” media have not evolved. Though, they’ve evolved somewhat in recent years; many European newspapers now have a deal with NYT and others to provide cross-newspaper accesses for paying customers.
Yet, why there still is no “Tinder” or “Spotify” for quality newspapers? I mean: I am not interested in everything, but I would gladly pay if I would have an opportunity to read the articles that interest me from the NYT, WSJ, Economist, etc., some major European newspapers, science and technology magazines, and so forth and so on, with a single subscription and a platform or app or whatever.
Jukka:
Magazine subscriptions are cheap. For example, the undiscounted cost of a year’s subscription to the London Review of Books is just $90, and this gives you lots more material than you’d get from an online newsletter that might cost $45. I don’t get it why so many people will pay for online newsletters but balk at subscribing to magazines. Maybe part of it is that if you pay for the newsletter, you see the money going directly to a person whose work you’d like to support, whereas with a magazine it’s indirect so you don’t get that same warm feeling that you’re helping someone make a living.
Jukka asked:
Yet, why there still is no “Tinder” or “Spotify” for quality newspapers? I mean: I am not interested in everything, but I would gladly pay if I would have an opportunity to read the articles that interest me from the NYT, WSJ, Economist, etc., some major European newspapers, science and technology magazines, and so forth and so on, with a single subscription and a platform or app or whatever.
Apple News has elements of such a compilation. It’s $13 per month and gives access to hundreds of publications including Scientific American, BBC Top Gear, WSJ, Times of London, Wired, NY Post, The New Yorker, . . . You don’t always get access to 100% of a publication and the format is changed to match a consistent Apple News format. But it’s a good deal if you want to browse lots of different publications. Unfortunately it does not include NYT or The Economist.
Another alternative is a public library. My library gives digital access to “6,449” magazines of which 232 are in Portuguese. Magazines from the library with new in the name include The New Yorker, New York Magazine, New Zealand Listener, New York Review of Books . . .
Bob:
Yeah, good point about the public library. I like to read physical magazines, but it’s good to be able to read full articles that people link to.
I described Apple News+ but referred to it as Apple News. Sorry.
There’s Readly – pretty well established.
“Yet, why there still is no ‘Tinder’ or ‘Spotify’ for quality newspapers?” What baffles me is that nothing seems to have happened with the micropayments idea that was all the rage with the talk of Web3 over a decade ago. I’d happily pay some reasonable small amount for the occasional article I want to read from publication X when I can’t justify paying a subscription for all of the content publication X produces for a year. A quick web search shows that discussion of Web3 micropayments resumed a couple years ago, but the idea doesn’t seem to have gotten very far. I’d like to see a discussion of why the idea has failed (and whether something like it could succeed).
“A bit of policy is fine, and there’s a lot of science to global warming, for sure. I wouldn’t want Scientific American to “bothsides” the issue.”
Why not “bothsides” global warming? If there’s a lot of science to it, which I believe there is, why can’t there be disagreement on the science–e.g., extreme events attribution analysis–or policy, e.g., will renewables or carbon capture/sequestration be effective solutions to the problem. It’s not comforting to see skeptics be derided as “deniers” or other ad hominem smears.
David:
I agree with you that presenting multiple perspectives on global warming, and discussing the (large) uncertainties involved, is useful.
I understand the term “bothsidesing” to refer not merely to expressing multiple perspectives and legitimate disagreement, but rather to the journalist practice of giving equal respect to legitimate and illegitimate perspectives.
For global warming, there’s a lot of uncertainty about what will happen, along with legitimate debate on potential mitigation strategies, ranging from strict leave-it-in-the-ground laws to carbon taxes to subsidies for renewables and nuclear to research on carbon capture to geoengineering, and all sorts of other things I haven’t mentioned. But I don’t consider it legitimate to show equal respect to the guy featured by Freakonomics who said, “The PDO cool mode has replaced the warm mode in the Pacific Ocean, virtually assuring us of about 30 years of global cooling.” It’s not a smear to call this guy a denier. He may be completely sincere; it’s still not a serious scientific position in the context of what is known about global warming.
Something similar came up a few decades ago with HIV and Aids. There was a fringe view that HIV did not cause Aids. In my view, there was nothing wrong with news outlets mentioning that this fringe view existed and sometimes interviewing its proponents. I’d only call it “bothsidesing” if they were to present the fringe view on equal footing with the legitimate research on the topic.
Yes, I think there’s a very important difference between the well understood physics side of it (more greenhouse gases blocking IR emissions requires the temperature to rise for fairly straightforward energy-balance reasons) and the more uncertain exactly-what-will-the-effects-be side. Especially when you move from ecological and weather effects to social and economic effects, since the latter will be highly dependent on social/governmental/technological changes which can be enormous over the relevant timescale.
Skepticism about claims of the second type (specific effects, especially social/economic ones) is something very different from skepticism about claims of the first type (overall connection between greenhouse gas emissions and warming).
“the well understood physics side of it (more greenhouse gases blocking IR emissions requires the temperature to rise for fairly straightforward energy-balance reasons)”
This did not work out so well, and a retrenchment is underway (Gavin Schmidt calls it “reflections about reflection”).
The basic physics have always been that extra CO2 forms an extra blanket by attenuating longwave radiation at the Top of the Atmosphere (TOA). Now we are coming up on 25 years of CERES data, and the data shows that the TOA energy imbalance is not in the longwave but rather in the shortwave. This means that the modern warming is due to more reflection of shortwave solar energy rather than more absorption of reradiated longwave. It doesn’t mean that increased CO2 is not ultimately the root cause, but it points back to changes in cloudiness that do not necessarily require a CO2 mechanism.
As an example of the sort of retrenchment that is now required, land use and deforestation can have a direct effect on cloudiness and shortwave reflection, while CO2 can only have an indirect effect, making land use/deforestation a more parsimonious explanation for the modern warming.
Oops, bungled that. It should have read that the modern warming is due to LESS reflection of solar shortwave.
Don’t think Gavin Schmidt’s “reflection on reflection” is about a “retrenchment” of understanding about the physics of global warming. His recent Real Climate post with that title is about yet another example of so-called “skeptic” non-science. He also highlights an error in the presentation of CERES data in a paper (Stephens et al. 2015). Nothing about a retrenchment.
Anyway, confused’s concise one sentence summary that you copied seems fine. Enhanced atmospheric greenhouse gases attenuate LWIR radiation to space which now escapes from the atmosphere at a higher average altitude than would occur at lower greenhouse gas concentrations. Since the atmosphere is colder at higher altitudes the Earth system warms up to raise the temperature at that altitude to that required to achieve radiative balance. That’s basically it – “straightforward energy balance reasons” as confused said.
Drilling down, there are several contributions to warming involving effects on LW and SW IR. I’m not aware of anything novel here, though I haven’t been following this stuff for years. Gavin Schmidt doesn’t discuss any new/updated/retrenched interpretations in his “reflection on reflection” article. The fact that return to TOA radiative balance may be dominated by feedback effects on SW IR has been known for a long time [see e.g. Donohoe et al. 2014, “Shortwave and longwave radiative contributions to global warming under increasing CO2” PNAS 111, 16700].
I haven’t visited the Real Climate blog for years, but depressingly nothing much seems to have changed – informative posts by people that know what they’re talking about accompanied by huge nonsense comment threads – in this case promoting solar cycles (there are some knowledgeable people on the thread). But it’s also been known for years that current global warming is a result of enhanced greenhouse (rather than solar variation) since stratospheric cooling is a clear signature of greenhouse warming and has been measured repeatedly – a recent update is : Santer et al. (2023) “Exceptional stratospheric contribution to human fingerprints on atmospheric temperature” PNAS 120 (20) e2300758120
Matt –
Seems like your comment is setting this up as an either/or: either the warming is from more CO2, or it’s from thinner clouds letting more sunlight through.
But why do those have to be two separate, competing stories? Couldn’t the clouds be thinning out *because* the planet’s already warming from the CO2—one thing feeding the other, rather than one replacing the other as the explanation?
What makes you confident the cloud change is its own independent cause, and not just another link in the same chain?
And here’s another wrinkle: Clouds affect both incoming shortwave and outgoing longwave radiation. So why assume that reduced cloud cover translates straightforwardly into net warming rather than requiring a full accounting of both effects? How did you calculate a net warming instead of a wash?
One more simple question, especially with reference to the “parsimony” of your theory that recent warming can be attributed to land use change rather than an increased accumulation of atmospheric CO2: aren’t we also constantly hearing that the planet is “greening” – more vegetation, not less, thanks to all the extra CO2? If global leaf area is actually expanding worldwide, doesn’t that cut against land use loss being a parsimonious driver for the change in reflected sunlight? Reaching for land-use shifts as the cleaner explanation seems to trade a single, globally measured radiative driver for a patchwork of local land shifts, which feels maybe not all that parsimonious.
I’ll leave the technical side of this to Chris’s comment above, which I found worth reading closely. But I’ll just say, as a simple observer, leading with “retrenchment” struck me as a bit of what I’d call “prior mining” – reaching for a conclusion first and working backward – rather than following where the evidence actually points. Chris’s comment suggests the evidence doesn’t point where you took it. And maybe that’s the real lesson here, tying back to confused’s original point: confused drew a clean line between skepticism about the basic physics and skepticism about downstream effects, and said the two are on very different footing. Your comment – projecting “retrenchment”‘ onto Schmidt and reaching for a land-use alternative over a physics-only claim – is a pretty good example of how often that clean line doesn’t hold up once you look at how actual climate “skeptics” argue.
I appreciate the cogent responses from Chris and Joshua. I will first respond to Joshua by saying that I am not ruling out CO2 as the primary driver, see below. The paper Chris linked shows how it would have to work. The problem is that nothing about the climate system or the data we have from CERES requires any role for CO2, which is why parsimony rears its ugly head. The retrenchment is not about abandoning CO of course (that will be a cold day in hell), but rather about focusing on the hydrological cycle in ways that seemed unnecessary before.
I did find one thing Chris wrote to be problematical: “Enhanced atmospheric greenhouse gases attenuate LWIR radiation to space…” I’m not sure why this was written here since this is precisely what the CERES data shows in NOT driving global warming, which in turn relates back to confused’s statement about energy balance which is also wrong (it is not “simple energy balance reasons” if the entire process has to go through the hydrologic cycle to result in cloud changes that result in SW rather than LW attenuation).
Chris is just using received terminology and that is fine, but it is really aggravating that the term feedback gets used so much in discussions about phenomena that have nothing to do with feedback and by people who clearly have no idea who control systems work. If there were positive feedback (a rare and unstable phenomenon!) in the climate system, solar irradiation of the earth would increase as the temperature climbs. The correct term is “knock-on effects.”
The overarching problem is that the knock-on effects – which are the misnamed topic of the paper Chris linked – that supposedly transform the absorption of LW into attenuation of SW constitute an entirely unnecessary step in the warming process and there are no direct measurements that support the inclusion of this step. There are also some aspects of the warming data that have never really fit the CO2 theory, such as the fact that most of the modern warming has come at night and in cities.
In summary, AGW theory based on CO2 remains supported by a strong correlation between CO2 rise and temperature rise, as well as perfectly reasonable GCMs that rely on knock-on effects to transform LW absorption into SW attenuation, as described in the paper Chris linked. But land use changes and deforestation provide a mechanism that resolves at least one problem that the CO2 theory does not, the spatial discrepancies in warming rate showing a significant Urban Heat Island effect, while providing a more parsimonious and direct explanation for the SW attenuation, namely alterations of the hydrological cycle that result in reduced reflection of SW to space. And then of course there is natural variation. We are now warmer than the global Medieval warming but not as warm as the Minoan warming, both of which remain poorly understood.
The Urban Heat Island is I think a completely separate effect, not something that’s competing or needs to be explained by a climate change model. It’s local rather than global.
I think clouds and land use changes are important, but they aren’t an argument against CO2 as primary driver.
I have however seen an argument that cloudiness and forest cover changes may be very important in shorter term changes, since CO2 tends to be long term (we wouldn’t expect year X+2 to be very much warmer than year X due to CO2 alone).
But ultimately the radiation balance has to … balance.
confused wrote:
“The Urban Heat Island is I think a completely separate effect, not something that’s competing or needs to be explained by a climate change model. It’s local rather than global.”
UHI is just a part of land use changes; here is a very succinct overview starting from first principles and refuting your claim about local rather than global:
https://physicstoday.aip.org/features/lands-complex-role-in-climate-change
Chris did an excellent job of keeping the discussion at the highest levels of the logic tree – observational evidence for direct causation – and it would be getting down in the weeds to talk about the evidence for the relative importance of specific land use phenomena such as UHI. Suffice to say that AFAIK there is no evidence that shows that the effects of land use changes are of insufficient magnitude to cause the majority of the modern warming, and the theory provides a more parsimonious explanation for the hydrological cycle changes that TOA measurements have shown have caused the warming.
Thanks Matt – I think the issue relates to the timescale of recovery of LW IR emission to space in a greenhouse-enhanced troposphere, which is why I referred to the Donohoe paper in my post. This paper indicates that LW IR emission can have a relatively fast recovery rate (decade timescale) following greenhouse gas perturbation, as a result of fast SW feedbacks that relatively quickly raise tropospheric temperatures to promote LW IR emission recovery (now from a higher altitude). That seems to be what’s observed in the real world. So while LW IR emission has not changed much as observed in the CERES data, the emission is occurring from a higher altitude for the reasons described in my post, and this can only have occurred via warming right through the troposphere down to the surface to pump up the temperature of the upper troposphere. We know this has happened since it’s been measured directly (the surface and tropospheric temperatures, that is – increased altitude of LW IR emission is determined less directly).
Greenhouse warming has resulted in sea ice and glacier melt (albedo contribution), and maybe cloud feedbacks (don’t have a handle on this) which do (less ice) or can (clouds) result in enhanced retention of solar SW IR, as well as moistening of the atmosphere through water vapour feedbacks etc.. So the primary cause of the warming remains the enhanced greenhouse effect even if heat accumulation now seems to be dominated by solar SW IR retention.
IMO it does come down to confused’s “simple energy balance reasons”! We’re still in a significant energy imbalance and so have more warming to come even if we could stabilise greenhouse gas concentrations right now. The earth surface at an atmospheric CO2 concentration of 300 ppm in 1900 was around 33oC warmer than it would be without the greenhouse effect. We’re not surprised that raising atmospheric CO2 to 430 ppm has caused considerable further warming.
On your other point, I don’t see the problem with using “feedback” in the manner that climate scientists use it. If we engage with a scientific field it’s really up to us to adopt the terminology that they use. In my research (molecular cell biol) we use “feedback” in a different way, but really what’s the problem? If one doesn’t like “feedback” why not mentally substitute “amplification” or something you prefer?
Matt –
We should def wrap up soon. The last thing this worlds needs, let alone Andrew’s blog, is a other climate change argument. But, well, you know…
I appreciate the thoughtful response and clarification, but I still don’t think it addresses the central question I was asking. My question wasn’t whether cloud processes matter, or whether the hydrological cycle is important. It was whether you’re proposing the observed cloud changes as an independent forcing, or as part of the causal chain initiated by greenhouse forcing. Your response explains why you think cloud changes are important and why you think land-use changes provide a more parsimonious explanation. But I still don’t see what justifies treating the cloud changes as independent rather than downstream. If they’re independent, what is the physical mechanism that produces coordinated global cloud changes without those changes themselves being driven by the changing thermodynamic state of the planet?
I’m also struggling with your claim of parsimony. CO₂ is a single, globally measured radiative forcing. Your alternative seems to require aggregating a vast collection of heterogeneous regional processes that could run bi-directionally – urbanization, deforestation, agriculture, irrigation, vegetation changes, and so on – into one dominant global mechanism that pushes in one net direction. That seems, at least to me, to increase explanatory complexity rather than reduce it.
And here’s a plain question that I keep getting stuck on: you objected to Chris’s explanation on the grounds that the greenhouse-to-cloud pathway leans on a step that isn’t directly measured. But doesn’t your own land-use-to-cloud-change story ask for the same kind of unmeasured leap? If a missing direct measurement is disqualifying, it seems like it ought to sink both explanations, not just the one. So what’s the difference that lets your version through the door while Chris’s doesn’t?
Relatedly, I’m not sure I follow the the link from land-use effects to UHI. Urban heat islands seem primarily relevant to localized surface temperatures, whereas the issue under discussion is the planet’s overall radiative balance. More generally, land-use changes are spatially patchy and often have competing effects on albedo, evapotranspiration, and cloud formation. What evidence shows that their net global effect is large enough to dominate the observed TOA energy imbalance, rather than acting as one contributor among many?
One final observation, tying this back to confused’s original distinction. I still think confused was drawing a useful abstract distinction between skepticism about the basic greenhouse physics and skepticism about downstream effects. But discussions like this illustrate why that distinction so often becomes blurred in practice.
Judith Curry is a good example. She consistently said she accepted the basic greenhouse effect, yet she also argued that global warming had “paused.” She and others proposed multidecadal variability as *the* explanation, but I never found that reconciled the two claims physically. It didn’t really explain how an ongoing greenhouse-driven radiative imbalance could produce what she described as a pause, as opposed to simply modulating the rate of warming. And, of course, the subsequent warming substantially weakened the empirical case that there had been a genuine pause in the first place.
I see something similar here. You’re explicit that you’re not rejecting CO₂ or the greenhouse effect. But as the argument develops, more and more of the explanatory work shifts elsewhere – to land use, cloud changes, the hydrological cycle, natural variability, and so on. The GHE remains acknowledged in principle, but increasingly ceases to do the explanatory work. That’s why I said earlier that, when you strip these arguments down to their explanatory structure, the clean distinction confused drew often becomes much harder to maintain in actual climate “skeptic” arguments.
Matt –
Apologies – on rereading, I need to repair what I just posted. You did answer my question and argue that cloud cover change is driven by land use changes, independent of CO2-driven warming. The rest of my comment stands, in that I still question why, once multiple causal stories are compatible with the observations, your particular causal mechanism becomes the more parsimonious explanation.
Joshua:
>>That’s why I said earlier that, when you strip these arguments down to their explanatory structure, the clean distinction confused drew often becomes much harder to maintain in actual climate “skeptic” arguments.
Oh, in practice as opposed to in principle, I agree with you.
But I think the distinction is important even if generally blurred.
I was also talking more about economic/social effect forecasts, or effects on specific local things, rather than cloud/world greening feedback stuff.
It’s amazing the claims Skaggs is making in the middle of this record-breaking-no-really-all-the-heat-records-on-land-and-water-have-broken heat wave summer. How would deforestation account for this without the greenhouse effect? Deforestation may indeed be a reason why the heating has accelerated so much in just a few years, but of course it is still a s ientiifcally undisputed fact that the heating is caused by the record high concentration of CO2 and other greenhouse gases.
I was going to move on but there seems to be confusion about the energy balance stuff. Confused wrote: ” “…the well understood physics side of it (more greenhouse gases blocking IR emissions requires the temperature to rise for fairly straightforward energy-balance reasons).” And Chris has endorsed this a couple times. I will try to lay out my objection as simply as I can.
When James Hansen and others first starting drawing attention to rising CO2 in the 1980s, the theory was based upon a 1898 paper by Arrhenius. In that paper, Arrhenius argued that CO2, as a mid-infrared absorber, would be expected to raise the global temperature as the concentration in the atmosphere rose. Because the CO2 bands have ALWAYS been saturated in the atmosphere by high concentrations of CO2, there is a decent bit of complexity I will gloss over here, but we can still call this confused’s “straightforward energy balance reason.” The energy balance at the Top of the Atmosphere (TOA) is a control volume (or mass, interchangeable in this case) boundary problem and really is straightforward. It is [energy in] – [energy out] = global warming.
Now let’s drill down one level on the logic tree. Incoming solar energy is called shortwave. The CO2 absorption band is saturated in the atmosphere, so that means that the energy being blocked by additional CO2 is energy that was re-radiated in the atmosphere. This re-radiated energy spills into lower frequency bands on the electromagnetic spectrum and so is referred to as longwave energy, energy that is re-emitted by CO2 itself lower in the atmosphere. The theory was that an additional blanket of CO2 will absorb more of this outgoing longwave, heating the planet. This is the “straightforward energy balance.” This is referred to (rather smugly IMO) as the “canonical view” in the paper Chris linked.
For most of its history, anthropogenic global warming theory has lacked any direct measurements. It would be lovely if we had data that showed more CO2 farther away from the surface, but we cannot measure that. Theories that show specific outcomes that match the physics such as enhanced stratospheric warming (h/t to Chris for mentioning this) are meaningful here, but not as valuable as a direct measurement. A third approach would be to show that Arrhenius was right by showing that the recent warming has been caused by attenuation of outgoing longwave, for the reasons described above. Enter the CERES satellite measurements around the turn of the millenium, which were intended to do just that.
Except it didn’t happen that way. The CERES measurements showed the opposite, that the planet has warmed from an attenuation of outgoing shortwave energy, not longwave. In other words, the straightforward energy balance reason for the warming was not what was happening. James Hansen et al had it wrong, Arrhenius had it oversimplified.
The paper Chris linked shows that by 2014, climate scientists were peeking at over 10 years of CERES data and knew they had a problem. So they re-parameterized the climate models to add an extra step where the CO2 warming is transformed into changes in cloudiness, which then result in attenuation of outgoing shortwave. And now the point of this last post on this thread: no matter how you stack it, no matter how you use your words differently than me, this is no longer the “straightforward energy balance reason” that existed prior to the CERES data. This is a complicated mechanism that starts with greenhouse gas physics and then makes a mysterious transformation into changes in the hydrological cycle resulting in more cloud reflection.
Dang, did it again. The last sentence should finish “…resulting in less cloud reflection.”
Hmmm.. it really is just energy balance stuff. The earth is currently in energy imbalance because the shortwave solar radiation absorbed by the earth exceeds the amount of longwave radiation emitted to space. This is largely due to an enhanced greenhouse effect.
The greenhouse effect manifests by attenuating outgoing LWIR radiation. With enhanced atmospheric greenhouse gas concentration LWIR emission to space recovers by emitting from a higher (and initially colder) average altitude. To recover radiative equilibrium the atmosphere warms up right down to the surface to pump the emission altitude to a temperature (around -18 oC IIRC) to achieve radiative balance. The warming is the result of absorption and retention of solar SWIR which is currently powering into the oceans at a prodigious rate.
I’ve said that a couple of times now – this has all been measured in the real world so isn’t controversial. The CERES data isn’t inconsistent with this. Why do you think it is?
Anyway, I don’t find your historical account very edifying – it seems like you’re trying to do some point-scoring! I do question a couple of things you’ve said and maybe you could provide some evidence for the following:
(i) You’ve said that the CO2 absorption bands have always been saturated. I don’t believe that’s the case – what makes you think so? (ii) You’ve said that the current earth surface temperature is not yet as high as during the “Minoan warming” – what’s the evidence for this? (iii) You are promoting the notion that clouds and land use changes/deforestation can account for current warming. That seems unlikely – can you link to some attribution studies that support that? In any case the cloud effects on retention of SW IR are likely to be a feedback response to greenhouse warming so is also a consequence of human greenhouse gas emissions and not something seperate– see e.g. Ceppi et al. (2026) “Emerging low-cloud feedback and adjustment in global satellite observations” Atmos. Chem. Phys., 26, 4153–4171.
I wonder whether we should wrap this up pretty soon!
Matt –
Because I think you still haven’t addressed an issue I raised twice, I’ll go with one more comment.
From my perspective there’s a clear asymmetry in the standards you’re applying to reach a conclusion of relative “parsimony.”
Your preferred explanation is explicitly an interacting dynamical system: land-use changes alter the hydrological cycle, which alters cloud cover, which changes the TOA energy balance. There’s nothing inherently wrong with that. But when the greenhouse account likewise becomes an interacting dynamical system – CO₂ alters the radiative balance, warming changes humidity, circulation, and cloud cover, and those changes then modify the energy balance – you describe that as evidence that the original greenhouse explanation has failed and required a “mysterious transformation.”
Why are interaction effects explanatory depth in one account but evidence of an ad hoc rescue in the other?
I’ll leave it to Chris to weigh in on the technical arguments (specifically the “no direct measurement, ever” claim). But even granting that premise, the asymmetry stands on its own: a multi-step causal chain is only disqualifying for the GHE.
Arguing that the GHE doesn’t exist and arguing that it becomes effectively irrelevant aren’t quite the same thing – but they’re basically kissin’ cousins. Curry’s “paused” claim is the sharpest version: if “global warming” means what it should – the total accumulation of energy in the system, not just the SATs – then claiming it paused while GHG forcing kept rising is a direct contradiction. The energy has to go somewhere.
The same goes for the argument that the surface record is too corrupted by UHI or “thumbs on the scale” to trust: you can’t use a record you’ve just declared unreliable to establish that warming paused.
Your arguments here don’t rest on that same kind of stark contradiction – you’re not claiming warming stopped, and you’re not claiming the data can’t be trusted. But I think it’s a similar epistemic pattern: you accept the GHE is real, then apply a more permissive standard to your preferred causal story than you apply to the GHE’s own explanatory chain, until the GHE’s contribution to what we’re actually trying to explain quietly shrinks toward irrelevance. The theory stays alive in name, but in your account its explanatory role survives only through what you describe as ‘retrenchment’ and a ‘mysterious transformation.’
” You’ve said that the CO2 absorption bands have always been saturated. I don’t believe that’s the case – what makes you think so?”
I performed infrared spectroscopy for over 30 years. I can’t just let this one hang.
CO2 has strong absorption bands in the mid-infrared at around 15 microns and 4.3 microns. The incoming solar SW energy at those mid-infrared frequencies is completely absorbed by CO2 high in the atmosphere, long before it reaches the ground. Because the incoming SW warms the atmosphere, the air, including the CO2, will reradiate thermal energy. This is broadband (“longwave”) energy and includes energy in the CO2 bands at 15 and 4.3 microns. This reradiating in the CO2 bands continues down to the surface and back up.
If you look at a spectrum of one foot of air in an infrared spectrometer, it will show a flat top on the CO2 peaks because the absorbance is so strong. None of the energy at 15 or 4.3 microns reaches the detector. Back to the atmosphere…if you point an infrared detector up towards the sun from the surface of the earth, none of the energy at 15 or 4.3 microns is from solar SW, it is all reradiated LW. This is what “saturated” means. There has always been enough CO2 in the atmosphere for this to be true and it has always been part of AGW theory.
Arrhenius knew this when he wrote his theory. The theory calls for an additional “blanket” of CO2 that absorbs more outgoing, reradiated LW, which is why the theory predicted that the CERES satellites would detect attenuation of outgoing LW, not the attenuation of SW that was actually measured.
Of course I bow to your experience with IR spectroscopy. However, it isn’t true that the CO2 absorption is saturated and even if it was it wouldn’t mean that adding more CO2 to the atmosphere wouldn’t cause additional warming since LW IR must escape to space to achieve radiative balance and will simply do so from a higher altitude (as I have related ad nauseum here). A short excerpt from a recent paper [1] covers both points:
The CO2 absorption (looking at the 667 cm(-1) absorption i.e. the 15 micron band you refer to) isn’t saturated even though measurements with early spectrophotometers made it appear so. Here’s an excerpt from Pierrehumbert (2011) [2] referring to some erroneous interpretations by Angstrom in the early 20th century :
I think you agree with the point that adding more CO2 to the atmosphere would still cause additional warming even if CO2 absorption was saturated.
Going back to CERES, I think we probably also agree that the decrease in SW IR in the CERES data indicates less solar SW IR reflected to space (more absorbed by the Earth system) – this is likely an effect due to albedo and cloud changes – it’s the cause of the thermal energy currently powering into the oceans. The much smaller increase in LW IR in the CERES data seems anomalous given the mechanism of the greenhouse effect but I don’t think it is. It relates to the timescale of LWIR recovery and the fact that CO2 has been added relentlessly into the atmosphere over a long period, rather than being added in a massive single slug:
It you picture an instantaneous slug of additional atmospheric CO2, emission of LW IR from the TOA would immediately reduce. Over time LWIR emission recovers as the earth and atmosphere warm up (greenhouse effect) pushing the average LW IR emission to higher atmosphere as radiative equilibrium recovers. This occurs broadly exponentially. If one switched on a CERES monitoring system at some time after adding the slug of CO2 one would see an increasing trend in LWIR emission even though the greenhouse effect results from attenuation of LWIR emission – the system is only seeing the recovery. I think that’s what we’re seeing now. Things are more complicated since there has been a continuous increase in atmospheric CO2 but CERES has only started collecting data well after the start of greenhouse emissions and LWIR recovery. SO LWIR hasn’t changed much but the emission height in the atmosphere has moved steadily upwards. That’s how I understand it.
1. Dufresne et al. 2020 Greenhouse Effect: The Relative Contributions of Emission Height and Total Absorption J. Climate DOI: 10.1175/JCLI-D-19-0193.1
2. R Pierrehumbert Infrared Radiation and Planetary Temperature Physics Today 2011 DOI: 10.1063/1.3541943
“I think you agree with the point that adding more CO2 to the atmosphere would still cause additional warming even if CO2 absorption was saturated.”
Yes. Arrhenius showed that!
Pierrehumbert is screwed up. First of all, when he refers to “the additional absorption in the wings of the 667 cm(−1) [band]” he is talking about pressure broadening, which is a different phenomenon and is not an argument against the simple fact of CO2 saturation. It’s also a tiny amount of energy. This is a crazy discussion! Of course the CO2 bands are saturated, we are talking about a strong absorber miles thick. The only thing “modern spectroscopy” showed is the pressure broadening.
Pierrehumbert’s second arguement that “the radiation only escapes from the thin upper portions of the atmosphere that are not saturated” is a non sequitur and shows he is out of his depth. Of course the radiation only escapes from the thin upper portions, the bands are saturated everywhere else!
I’m afraid that now we have reached garbage time with the Pierrehumbert quote.
Matt –
> “I performed infrared spectroscopy for over 30 years. I can’t just let this one hang.”
I was going to just let this convo lie, but I just can’t let this one hang!
Assuming I could roughly parse the technical discussion well enough to get a fair general sense of it, I see an interesting link between your (selective) appeal to (your own) authority here and the flexible standards you’re using to attribute relative “parsimony.” There’s nothing wrong with invoking relevant expertise, of course. But “I’ve done IR spectroscopy for 30 years” seems to be about more than simply establishing relevant background. Based on the details of your arguments, you seem to be using your expertise in one setting – perhaps primarily laboratory applications of spectroscopy? – to adjudicate what happens in the very different setting of the atmosphere, and then rather summarily waving away someone whose expertise is specifically in that area as “out of his depth.”
That seems like a mirror image of the appeal to authority that climate “skeptics” so often object to: expertise isn’t supposed to settle an argument – except here your own expertise seems to be driving your analysis as well as your rhetorical approach. And as an outside observer, the step that seems most in need of justification is precisely the one that laboratory experience doesn’t obviously settle. I don’t doubt that a foot of air in a spectrometer – as you brought up as your benchmark – can completely absorb radiation at particular wavelengths. But how does that apply to an atmosphere that isn’t a foot-long, relatively uniform sample, but is instead miles deep, with temperature, pressure and density changing dramatically as you go up, and with energy being absorbed and re-emitted throughout. Chris’s cited argument seems to be about where – and at what temperature – energy can finally escape to space as CO₂ increases. I don’t see how your description of benchtop radiative physics, by itself, disposes of that.
Which brings me back (again) to this notion of parsimony. You seem to demand direct physical validation of the intermediate steps when the causal chain runs from CO₂ through the climate system, but you’re much more comfortable extrapolating across intermediate steps when the chain starts from land use – or, here, when the inference starts from your own spectroscopy expertise.
Of course things look more parsimonious once you’ve already picked a starting assumption that rules out whatever would complicate the parsimony conclusion.
For Joshua:
“Canonical” AGM:
[Incoming solar SW warms the planet]
1. Excess CO2 traps more LW radiation, raising temperature.
2. (Predicted) attenuation of outgoing LW at TOA.
Reworked AGM after CERES data showed attenuation of SW at TOA, not LW:
[Incoming solar SW warms the planet.]
1. Excess CO2 traps more LW radiation, raising temperature and attenuating outgoing LW for a while, which was unfortunately not measured.
2. Higher temperature leads to cloudiness changes, while outgoing LW returns to the pre-industrial equilibrium, which was unfortunately not measured. Higher temperature affects cloudiness.
3. Cloudiness changes lead to attenuation of outgoing SW measured at TOA.
Land Use Theory (after Roger Pielke Sr.):
[Incoming solar SW warms the planet.]
1. Land use changes cause cloudiness changes.
2. Cloudiness changes lead to attenuation of outgoing SW measured at TOA.
Matt, Chris, Joshua
To properly make a model of the radiation transmission we need some extended mathematical model like a PDE or perhaps integral differential equation.
Light comes in with a broad spectrum, there are specific absorption bands for CO2, but after absorption there is reradiation of a wide spectrum of radiation, some of which is reabsorbed, etc etc.
Matt is I’m sure right that the narrow band absorption is saturated in the sense that even over short distances of a few feet it can’t penetrate. but the secondary reradiation and absorption process must also occur. Radiation into space occurs at the top of the atmosphere because there are not enough molecules above that height to absorb that radiation.
You can imagine a long corridor with dogs digging in sand, each dog digs wildly flinging sand everywhere… including into the area of the other dogs… so any grain of sand (packet of energy) can’t travel very far directly, but eventually at the ends of the corridor the last dog does fling some of the sand out of the corridor into the garden.
saturated absorption can be likened to the drag on the sand particles. no matter how hard a dog flings the sand, aerodynamic drag keeps the particles from traveling far down the corridor.
The analogy isnt perfect but the point is that I am sure Matt is right about saturation in this sense, but I dont know what we are really arguing about here. energy from the sun comes into the atmosphere, is absorbed, reradiated, and then at the top of the atmosphere some escapes to space and leaves… this is all well established.
What is the controversy?
Matt, we crossed paths thanks for your summary.
Next, shouldn’t CO2 concentration in the atmosphere lower the mean propagation distance of a photon of CO2 absorbable IR? Doesn’t this then change the story? Let’s say we have a mean penetrstion of 1ft at some time in the past and now its 6 in… the diffusion time to get to space changes no?
“Top of the atmosphere” is a bureaucratic term, its not based on physics. Why not use the tropopause instead? This is non-arbitrary and approx constant at whatever altitude is at ~0.1 bar across planets:
https://www.nature.com/articles/ngeo2020
Matt –
It’s easy to miss in real time, comment by comment, just how much you’re fusing rhetoric and physics. Stacked together, it’s starker:
“a retrenchment is underway”
“the sort of retrenchment that is now required”
“canonical view” (“rather smugly IMO”)
“parsimony rears its ugly head”
“cold day in hell”
“getting down in the weeds”
“no idea how control systems work”
“James Hansen et al had it wrong, Arrhenius had it oversimplified”
“no matter how you use your words differently than me”
“mysterious transformation”
“modern spectroscopy” (in scare quotes, no less – despite the 30 years)
“this is a crazy discussion!”
“[Pierrehumbert is] screwed up”
“[Pierrehumbert] is out of his depth”
The pattern is quite noticeable. The mainstream account is repeatedly characterized as retrenchment, smugness, mystery, confusion or incompetence, while your alternative gets described in terms of “parsimony.”
I dunno, maybe it’s true that a leading expert in radiative physics is wrong here. But citing your own experience to qualify him as being “out of his depth” seems like a pretty extraordinary claim.
And the Pielke Sr. citation in your latest comment looks like another instance of the same pattern. You’ve now reduced the comparison schematically to CO₂ → warming → clouds → SW versus land use → clouds → SW. So the relative “parsimony” is right there visually: three steps versus two. Demanding a measured, physical account of every step on one side while compressing a genuinely complex, heterogeneous set of regional dynamics into a single bullet is an asymmetrical burden of proof. I wonder if the step count is partly a function of your choice to carve up the two causal stories, rather than a property of the physical dynamics themselves?
One question on Pielke specifically, without getting into the underlying science: is Pielke’s work actually establishing a global, dominant land-use → cloudiness dynamic – on the same footing as the global forcing you’re arguing it displaces – or is it establishing local/regional effects that have to be weighed across heterogeneous land-use changes and other competing effects to arrive at a net global effect?
That distinction matters a lot for whether “land use changes cause cloudiness changes” can really occupy one clean line in your comparison. If it’s the latter, it seems like you’ve made a choice to build some of the parsimony into the schematic itself – which looks to me like another instance of the rhetorical imbalance above.
Matt –
And another point on the same theme. Looking again at your pre- versus post-CERES schematics: aren’t you drawing the pre- vs. post- comparison at different levels of resolution?
Clouds and the hydrological cycle didn’t suddenly become an additional step in the climate system after CERES. They were always “canonically” among the things that could change as the planet warmed – as Chris’s citation already established, cloud and water-vapor feedbacks have been standard components of climate models since the 1960s, decades before CERES existed. What may have changed is how much explanatory weight those interactions carry in accounting for the observed TOA changes.
But you can create or eliminate arrows just by changing the level at which *you* describe the causal chain. I’m wondering if your “retrenchment” is really just your decision to draw out, as a separate step, one interaction among a group that were there all along. Your “pre-” schematic just didn’t show them – so the step-count you’re using to argue “parsimony” may just be an artifact of where you chose to draw the boundaries.
Matt –
I promise this will be my last comment on this thread no matter what.
But I couldn’t let this one hang!
I went back and looked over your 2014 essay, “Root Cause Analysis of the Modern Warming,” at Climate Etc.
Land use doesn’t appear anywhere in it – not in your fault tree, not in your detailed expansion of the “albedo decrease” branch, and a full-text search of the hundreds of archived comments turns up zero mentions of it either.
Your explicit conclusion back then was that the tree couldn’t be resolved, because high-fidelity evidence simply didn’t exist to evaluate each leg – full stop, no candidate declared.
Pekka Pirila pointed out in the comments why that approach was flawed from the start: root cause analysis and fault trees are designed for binary failures in stable engineered systems. Climate dynamics are continuous and multi-variable, requiring quantitative weighing of multiple overlapping, simultaneous forcings and feedbacks, rather than isolation of a single “broken part.”
Your current comparison on Gelman’s blog drops you right into the trap Pekka warned about. If you’re still playing by your 2014 rules, land use isn’t a root cause your methodology uncovered – it’s a candidate you plugged in years later because CERES data showed shortwave changes, *skipping the year-by-year, joules-per-year evidentiary work* your own framework said was required before declaring a conclusion.
And if you’ve abandoned those rules for a multi-variable view instead, then drawing “land use” as a clean two-step schematic against a three-step CO2 model becomes a visual trick: compressing complex regional dynamics like evapotranspiration, aerosol loading, and surface albedo shifts into a single arrow draws a bigger black box around that same complexity, without actually resolving it into a simpler physical mechanism.
Either way, the “parsimony” you’re claiming looks to me like an artifact of how you’ve drawn the diagram, rather than something derived from the physics.
http://judithcurry.com/2014/10/23/root-cause-analysis-of-the-modern-warming/
Pielke:
“As I have summarized on the Climate Science weblog, humans activities do significantly alter the heat content of the climate system, although, based on the latest understanding, the radiative effect of CO2 has contributed, at most, only about 28% to the human-caused warming up to the present. The other 72% is still a result of human activities!“
I wonder what the political motivation for this is. Most climate denialists are mad about the possible “authoritarian” (read: “requiring reining in large corporations”) policies needed to address climate change. The chain of logic/emotion goes:
1. CO2 causes warming
2. Policies I don’t like are needed to address it
3. To remove the need for these policies I will deny (1) or deny similar statements
Maybe Matt (and Roger) want deregulation of land use as their solution to warming instead of reining in polluting companies. Matt, is that right?
Anonymous –
Breaking my promise already…
Matt’s pretty much a lefty. I think trying to reverse engineer his scientific views from your assumptions about his politics is the kind of epistemic better left for climate change “skeptics.”
I think you misread the Pierrehumbert quote Matt. Firstly, the spectral region encompassing the 667 cm(-1) band isn’t saturated in the earth atmosphere. It is in the centre of the band but not in the less opaque regions to the side of the centre. Pressure broadening doesn’t preclude absorption in these spectral regions – I expect it actually increases absorptivity by spreading the sensitive wavelengths across a wider spectral region. Secondly, when Pierrehumbert refers to “radiation only escapes from the thin upper portions of the atmosphere that are not saturated”, he’s referring to Venus not the earth. So not a non-sequitur despite your impressive display of contempt!
One can assess this further by observing computed wavelength-dependent radiative forcing in different atmospheric compositions which indicates significant contributions from wavelengths in the wings of the main absorption band and regions further outside this [see Figure 1 of Mlynczak, M. G., et al. (2016) Geophys. Res. Lett. 43]. This helps to understand why efforts (difficult!) to determine direct satellite measures of effects of enhanced CO2 on longwave IR emission assess parameters outside of the central absorption band [ e.g. Teixeira et al. (2024) Atmos. Chem. Phys. 24, 6375].
There’s no question that the CERES time series is somewhat anomalous with slightly enhanced LW IR and substantial reduction in SW emission dominating the record especially in last few years consistent with the large ocean warming and increase in earth energy imbalance. That seems to be causing quite a stir. However, we’ve been here before; faux-“skeptics” made great play over the apparent lack of upper tropospheric warming and also the so-called warming “pause” that Joshua referred to. In each case while dreary characters were declaring the demise of climate science, the actual scientists sorted out the confusions. I expect this will happen again with the CERES data.
anonymous’s point about “political motivation” is a good one. In these sorts of discussion it starts to get more interesting to consider the motivations of (some of) the discussants rather than the topic of the discussion. Anonymous is probably correct that science denialism of various forms can arise from distaste around potential “authoritarian” policies. I tend to think about this in terms of large-P and small-p motivations where “p” is “political”.
So an anti-authoritarian mindset (which seems quite a resonable point of view, though susceptible to hijacking by demagoguery) corresponds to a small-p motivation. I’ve experienced other small-p motivations including an “I know better than them” attitude – often from retired engineers (apols for snark!). Also it’s satisfying to feel part of a group with a common interest, in this case whose members might share an excitement over subversive views against the scientific establishment. Unfortunately, small-p motivations can be taken advantage of by those with large-P motivations, as manifest, for example, in corporate funding of climate science skepticism. That’s all pretty obvious but it is interesting to consider how things get to be the way they are.
Chris wrote:
“the spectral region encompassing the 667 cm(-1) band isn’t saturated in the earth atmosphere”
Now it’s the “spectral region.” This is the third time you have moved what you think are the goalposts. You really don’t understand what I mean when I say the CO2 band is saturated, do you? Are you thinking that I mean that the concentration is saturated, like CO2 is going to start plating out on rocks?
I didn’t say anything about the spectral region. I said the central absorption band is saturated. If you create an infrared detector band of a single wavenumber width at 667, that wavenumber band is already fully saturated high in the atmosphere, long before you get near the surface. Let’s step through this so you can understand what you are talking about.
CO2 forms a sharp, Gaussian band in the mid-infrared. As solar SW penetrates, it gets lower in the atmosphere to a higher and higher concentration of CO2. On an infrared spectrum, the central band of the peak reaches 100% absorbance already high in the atmosphere, which is shown on the spectrum as a flat top to the band. The flat top means that 100% of the energy at 667 wavenumbers (not the spectral region, the wavenumber band!) was absorbed higher in the atmosphere. No matter how much you crank down the sensitivity of the spectrometer, you can’t get the flat top of the band to go away, because there is simply no energy reaching the detector at 667 wavenumbers. That is literally the definition of a saturated infrared band and is not a topic for opinions and debate.
You (and Pierrehumbert) are wandering around the concept of pressure broadening as if that has some sort of bearing on the saturation of the central band. The two concepts have nothing to do with each other. As the energy gets deeper in the atmosphere, the concentration of CO2 increases, causing the magnitude of the Gaussian CO2 peak to grow. As the magnitude grows, the tails of the Gaussian distribution (Pierrehumbert’s “wings”) move farther apart, bleeding over into additional wavenumber channels farther from 667. This means that CO2 absorbs some incoming energy at the ever-growing tails of the Gaussian distribution all the way down to the surface of the earth, since those tails are now bleeding over into additional channels farther from 667 where there is still incoming solar SW. Despite this pressure broadening effect having to do with <1% of the energy, this is often used as a sort of "gotcha" by climate scientists, which is why you brought it up here, but it seems none of you really get what it means for an infrared band to be saturated.
That’s not right Matt. Is it not you that has moved the goalposts? I responded up the thread to your assertion [August 6, 2026 12:08 PM at 12:08 pm] “Because the CO2 bands have ALWAYS been saturated in the atmosphere by high concentrations of CO2…”, which I thought couldn’t be right.
Now you say in your recent post “I didn’t say anything about the spectral region. I said the central absorption band is saturated”. But that’s not what you said. If you had said that I wouldn’t have queried it. We don’t disagree that the centre of the 667 cm(-1) band is saturated in the Earth atmosphere. The wings of the band and other IR modes are not saturated, so your statement that “the CO2 bands have ALWAYS been saturated…” is incorrect.
You also just said “You (and Pierrehumbert) are wandering around the concept of pressure broadening as if that has some sort of bearing on the saturation of the central band.” That’s also not true. You were the one that brought up pressure broadening! [August 7, 2026 5:33 PM at 5:33 pm] ”Pierrehumbert is screwed up. First of all, when he refers to “the additional absorption in the wings of the 667 cm(−1) [band]” he is talking about pressure broadening, which is a different phenomenon and is not an argument against the simple fact of CO2 saturation.. Since you brought it up I thought about it. Of course, none of us consider “broadening as if that has some sort of bearing on the saturation of the central band”. That’s silly and I don’t know why you would think we would think so.
To my mind the problem is in considering that discussion of climate science has to be adversarial.
Andrew, thank you for your thoughtful reply. I understand the need for editors to exercise some discretion over fringe articles that come their way. My negative reaction to using bothsidesing stems largely from the SciAm’s 150th Anniversary issue, which I found heavy handed on the issue. Especially off-putting was the magazine’s claiming for itself the role of gatekeeper, which suggested to me that reasonable disagreement, especially on policy solutions, could be dismissed as misinformation. Let’s hope the new owners find a better balance than the outgoing regime.
Wasn’t the 150th Anniversary issue in September 1995?
“It’s not comforting to see skeptics be derided as “deniers” or other ad hominem smears.”
I’m reading this on the first day of the *fourth* heat wave affecting Europe this year, and it’s still July. Each of the preceding three heatwaves were historically totally unprecedented and the fourth one is likely to also be record-breaking. We have been afflicted by record-breaking forest fires in France and elsewhere and the drought is also unprecedented. The number of people who have died from the heat is in the five digits. People are suffering, the vegetation is suffering, agriculture is suffering, livestock has had to be slaughtered for lack of water. I could go on. There is absolutely no scientific doubt about what causes these events. No doubt whatsoever, and the so-called skeptics know it perfectly well. Not a single one of them believes their own lies.
But sure, let’s give these climate change “skeptics”, people who promote lies on behalf of the fossil fuel oligarchy, more media exposure. These people (almost exclusively men) have blood on their hands. They are absolutely eager to burn the planet for whatever short term monetary or psychic wages they might gain. They are among the very worst people on this planet.
Between covid and iran, Trump has done more to fight global warming than any other politician. First demand destruction, then supply restriction far greater than anything else that has been done. Neither seemed to have any effect.
Anoneuoid –
> “Neither seemed to have any effect.”
It would be absurd to expect to see a measurable “effect” (either way) in global surface temperatures, ocean heat content, or extreme weather from either event because – other forcings (and greenhouse gas emissions) being equal – climate is driven by the total cumulative stock of atmospheric CO2, not brief fluctuations in CO2 emissions.
With Covid we saw a temporary, measurable drop in the rate of global emissions, but global emissions were still massively positive, so the vastly larger, accumulated atmospheric concentration of CO2 barely moved. Of course a very brief slowing in the rate of addition is far too small to show an “effect” on global temperatures, which lag atmospheric concentrations by decades.
With Iran – A temporary supply restriction in flow of oil doesn’t automatically reduce global emissions. Markets adapt through fuel-switching, drawing down stockpiles, or ramping up other production. Plus there’s still that whole stock and lag thing.
In both cases, the expectation of an immediate, visible signal in global warming misunderstands the relevant physics. Neither event would be expected to produce an observable change in “global warming” on the timescale you’re talking about.
I thought Anoneuoid was being purposefully sarcastic (though you can never know). I think the point about the actual effects of Trump’s actions was meant to balance the more obvious superficial interpretation that Trump’s “climate change is a hoax” clearly means he has contributed to global warming. The points about time scale and size of effects are certainly valid, but I thought (hoped) that Anon was simply pointing out that things are more subtle than they might appear. But if Anon really meant that Trump has contributed to combating global warming, then I will revise my assessment of the comment.
Dale –
Of course he was being sarcastic about the Trump “fighting” global warming part. I certainly hope he was being sarcastic about the visible “effect” part. I’d imagine he has a pretty good understanding of the relevant physics – which makes the comment about not seeing an “effect” absurd..
@All
Please tell me what any politician has done to stop warming and how we would determine the effectiveness of their actions?
Focus on actions, not words. And results, not intent. Its easy for scammers to tell you they care about climate then do nothing.
Finally, if the drastic and painful lockdowns and closed SoH are insufficient to have any effect, what will it take according to “science” to tell if anything is working?
Anoneuoid –
OK. This convo never had a huge change of being productive – but I will allow myself one more response and I won’t give in to any further temptation. Beyond that, I promise I’ll just go with “someone’s wrong on the Internet.”
Your latest comment is a weird mashup of several different implied arguments.
One is that the policies we’ve implemented so far haven’t been sufficient to measurably change the trajectory of global warming. On that point, I largely agree. I think we haven’t as of yet, for the most part, implemented policies on the (global) scale that would be expected to produce a detectable change in the long-term climate response.
Your second implied argument is that there’s no conceivable set of policies that could do so. That’s a much bigger question, and I’m not going to try to litigate it here.
But the third implied argument is the one I find most interesting because it’s just bizarre: the suggestion that, if policies were working, we should already expect to see a measurable signal in global surface temperatures, ocean heat content, or extreme weather.
The theory of global warming is that recent climate is driven primarily by the accumulated atmospheric stock of greenhouse gases, not short-term fluctuations in emissions.
Even a substantial but temporary reduction in emissions would barely change atmospheric concentrations, and because of the inertia in the system, it would respond to changes in concentrations with substantial lags. Looking for an immediate signal in global warming is simply looking at the wrong variable on the wrong timescale.
What’s especially odd is that I’ve seen you make technically sophisticated arguments about climate physics before. They may or may not be consistent with the mainstream scientific understanding, but they at least reflected someone who has thought seriously about the underlying physics.
That said, I can remember at least one previous comment where you seemed to lose sight of one of the most basic implications of that physics: the relationship between timescale and observable effects. This latest comment reaches the level of being fairly called bizarro-world reasoning about the physics.
@Joshua: I fear that the necessary time lag between reduced CO2 emissions and temperature effects being visible means that “purely” political efforts are pretty impractical in many places – costs will be seen before the next election, but not benefits
However, it makes a big difference what the non-climate drivers are. For a country that does not have significant local oil production or refining, there are strong non-climate reasons to push for electrification etc. For a small and densely populated country, electric vehicles are “easier” than for places like the central/interior-west US where distances are long and population is sparse. Both those effects, combined with the growing rural/urban divide in the US, make climate stuff a really hard political thing in the US.
(…it also doesn’t help that the few real attempts have been badly done and thus easy to target politically.)
confused –
Sorry, I missed this comment from you. I totally agree. The lag makes implementing policies politically unpalatable. I’m not convinced about the costs per se – once you factor in externalities such geopolitics (look at the iran war as a timely cost factor); the health costs of particulate matter – it’s not clear to me that the cost of mitigation is actually higher. But again, that a very difficult argument for marshalling political will – especially considering the powerful entities aligned against it.
Joshua – i meant the costs immediately visible to the average voter, not the real overall costs. Particulate matter health effects (as with most air pollution… barring a Bhopal type event or a major deadly smog) are generally a higher rate of bad things already happening, so not very visible in that sense.
“First demand destruction, then supply restriction far greater than anything else that has been done. Neither seemed to have any effect.”
A totally weird claim and quite unclear what it’s supposed to mean. If he suggests that the temporary reduction in oil availability on the world market should have had an effect on the climate, that is nonsensical. Evene if we stopped emitting GHG tomorrow, the climate crisis would not go away – but it would at least stop getting worse. But of course we are light years away from that goal. Even if oil consumption fell by a few percent “thanks” to Trump, that wouldn’t have had a big impact on CO2 concentration (https://gml.noaa.gov/ccgg/trends/). If there is a positive effect, it is that at least some countries and many consumers have understood the urgend need to get away from fossil fuels.
Yes, I still await to hear what any other politician has done that has been more effective. As I said, Trump has done the *most* and it still appears irrelevant. No one could get away with whats happened under his administrations with climate as an excuse.
I ask again, since everyone ignored my questions.
1) Rhetorical (since its obviously zero): What is the evidence any politician has done something to reduce warming?
2) Less-rhetorical: What would that evidence look like if it did exist, and what would it take to see it according to “science”?
Like Chris below, where it was claimed some EU politicians are doing something to defend against the warming. Meanwhile their elderly are dying in the tens of thousand from the heat because AC is too expensive.
Anoneuoid
I mostly agree with your assessment – if we are looking at static results. But climate change is a dynamic process and addressing its consequences will be dynamic as well. In my view, Trump has set back the timetable for reducing human impact considerably and others (yes, maybe even Biden’s Green Deal) have tried to facilitate it. Politics ultimately is tied to public willingness to change behavior and to reduce global warming (or species extinction) will require changes in human behavior. What politicians do impacts that, but I’m not sure how to measure that. But I think those measurements are likely to be quite different than the measurements of impact that you are focused on.
The way to reduce impacts without much public willingness is through autocracy, and that seems to be the way we are headed. The problem with that ‘solution’ is that it can work to reduce – or to increase – human impacts. So, I see it as increasing uncertainty and increasing potential dangers. I think Trump has had a significant impact on the trend towards autocracy. I’m not sure what a good measure of this is, but the evidence seems everywhere (Congress, the Courts, the Parties – both of them, and political candidates).
I think more of them are honest (though wrong) than you think. The effects of global warming may be extremely obvious in Europe, but they’re not necessarily obvious everywhere. Here in Texas, winters are expected to be chaotic (sometimes cold sometimes warm) and summers to be terribly hot. The warming is obvious when you look at weather statistics over the last 50 years… But it’s not necessarily blatantly obvious at the level of “lived experience”, in this climate. People who are old enough still say 1980 was ‘the worst summer ever’, even though 2011 beat it on some metrics (1980 still is all time record high for the area though … recent rises in my area seem to be more very high overnight lows than new record highs).
And very few people are old enough to compare with the, say, 1940 climate.
Much of Europe has a much lower level of “expected” extreme weather, I think in general higher latitudes are affected more/faster by climate change, and also things like snow melting earlier in the spring / lake ice melting are much more blatant/obvious than anything we’d see in a climate where snow does not stick to the ground for more than a day or two and lakes do not freeze.
Looking further into this, it’s not just that warming is less obvious in places where summer is expected to be miserable & snow is not expected to stay on the ground – there’s genuinely an area of the central US that has warmed much less than areas around it, especially in summer max temperatures (the so-called “warming hole”). And my own area is on the fringe of that.
So it’s not just that some changes are more obviously perceptible than others – some regions are more affected than others. The older people in my area who say summers have always been super bad and the current ones are nothing special may actually be right *for my area*, though not *globally*.
In Europe Ursula von der Leyen, is a good example, also Teresa Ribera in Spain – perhaps women are less willing to lie through their teeth in support of corporate agendas?? I don’t know – most of the science deniers that Piglet refers to are male.
Easy to determine effectiveness as you know very well. Your last question is a masterpiece of false equivalence and overgeneralization!
apols, didn’t nest that properly – was a response to Anoneuoid