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You are here: Home / Climate Science / Unforced Variations: Aug 2025

Unforced Variations: Aug 2025

1 Aug 2025 by group 229 Comments

This month’s open thread. Please try and stay focused on substance rather than personalities. There are many real issues that are particularly salient this month, and so maybe we can collectively try not to have the comments descend into tedium.

Note: Moderation will be applied to over-frequent and pointless commenters (you know who you are, and no, we don’t care to argue about it).

Filed Under: Climate Science, Open thread, Solutions

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229 Responses to "Unforced Variations: Aug 2025"

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  1. David says

    1 Aug 2025 at 11:16 AM

    “Trump administration cancels plans to develop new offshore wind projects”

    “The Trump administration is canceling plans to use large areas of federal waters for new offshore wind development, the latest step to suppress the industry in the United States.”
    .
    https://apnews.com/article/trump-wind-permitting-offshore-7a05dff77ba92e4a7761604583a6d208
    .
    And the next step backwards is coming fast: “The Interior Department is considering withdrawing areas on federal lands with high potential for onshore wind power to balance energy development with other uses such as recreation and grazing. It also will review bird deaths associated with wind turbines, which are allowed under federal permits that consider the deaths “incidental” to energy production.”
    .
    All the lost American jobs and economic benefit because of Trump’s personal aesthetics and a lingering wounded pride for losing a court battle in Scotland over a few offshore wind turbines viewable from one of his courses:
    .
    “Trump’s war on windmills started in Scotland. Now he’s taking it global
    President’s opposition to offshore wind more than a decade ago now threatens a huge industry in the US and beyond”

    https://www.theguardian.com/us-news/2025/jul/24/trump-clean-energy-war-global

    Reply
    • nigelj says

      1 Aug 2025 at 5:01 PM

      “And the next step backwards is coming fast: “The Interior Department is considering withdrawing areas on federal lands with high potential for onshore wind power to balance energy development with other uses such as recreation and grazing. It also will review bird deaths associated with wind turbines, which are allowed under federal permits that consider the deaths “incidental” to energy production.”

      The impact of wind turbines on people hiking and cattle grazing is insignificant, because people can easily walk and cattle can easily graze within a wind farm, and under the turbine blades, and without the areas of walking and grazing being significantly compromised. While the turbine blades have a large diameter, at ground level the footprints of the wind turbine towers are small, and add up to a very small fraction of the land area of a wind farm.

      Regarding bird strike:

      “In his 2013 Report , The avian benefits of wind energy , Benjamin K. Sovacool assesses the number of bird fatalities associated with various energy sources based on meta-analysis and a collection of results from experiments from across the country . His findings indicate that on average , wind turbines killed .3 to .4 birds per GWh of electricity they produced , while coal killed approximately 5.2 bird per GWh (Sovacool 2013) . Standing alone , these numbers are indicative of the marked increase in harm done unto bird populations posed by coal….”

      https://websites.umass.edu/natsci397a-eross/whether-or-not-wind-turbines-are-a-significant-threat-to-bird-populations/#:~:text=His%20findings%20indicate%20that%20on,per%20GWh%20(Sovacool%202013)%20.

      The commentary explains the reasons.

      Reply
      • Ron R. says

        2 Aug 2025 at 10:06 AM

        Honestly, when I’ve seen them, I wonder why they can’t put a very narrow hard to see wire cage around them to protect birds?

        Reply
        • Nigelj says

          2 Aug 2025 at 11:30 PM

          Ron R, a wire cage around the wind turbine blades would need to be very visible or the birds might fly into the cage and still injure themselves and so you end up with something a bit ugly like a pedestal fan, and costs might be quite significant. I think your other ideas about deterring birds with sound or making the blades more visible are more attractive options, and lower cost. Apparently painting one blade black makes the spinning blades much more visible.

          Reply
          • Ron R. says

            3 Aug 2025 at 10:13 AM

            ”Ron R, a wire cage around the wind turbine blades would need to be very visible or the birds might fly into the cage and still injure themselves”

            Yeah, I thought of that right after I posted it. :(

            I like the streamers/reflective tape idea. Farmers use them now for that very reason. To deter birds. Just put them all along the bottoms of the blades. And they can be attractive too!

            The sonic/ultrasonic sounds idea might work too. Try things.

          • David says

            4 Aug 2025 at 10:33 AM

            Painting blades has thus far shown mixed results. Some studies show a significant decrease in avian fatalities, others have shown little change. You have to be careful about attaching anything to a blade. The tip speed can easily exceed 150 mph and unintended vibration concerns arising from attaching unstudied items to the airfoil that a blade is warrant careful consideration and lab testing.

            Also paint does not address nighttime operation, when bats are about and some small birds migrate. I am glad to see that people are looking at the problem and in the end, we will do the best we can.

            All this because one man wants to destroy an industry because of his personal aesthetics and wounded pride over a lost court case years ago. We used to have a news media that would challenge our leaders, but no more. Now, as in this case, largely they are afflicted with dual diseases, cowardice (afraid to lose a place at the trough) and a profound ignorance of science.

        • Karsten V. Johansen says

          10 Aug 2025 at 5:38 AM

          1. Vertical axis wind-turbines https://en.m.wikipedia.org/wiki/Vertical-axis_wind_turbine is a solution to this problem, as well as the problem that traditional windmills are unable to function at higher windspeeds. Problems with breaking/fracturing wings could also be reduced.

          2. More important is that the most effective and stable/weather independent renewable energy source is *heat energy from the ground* , see https://en.m.wikipedia.org/wiki/Geothermal_energy and – available everywhere and cheaper https://en.m.wikipedia.org/wiki/Ground_source_heat_pump , using heat energi from seawater etc. I don’t quite understand why this is often almost completely overlooked. Is it maybe because it can’t be explored in very centralized energy systems and therefore isn’t tempting for the big oligarchs nowadays controlling the socalled “free” market and thus the political power in the USA, Russia etc.? The main problem with the market is that the competition creates oligopolies/cartels and monopolies…: Elon Musk, Peter Thiel, Mark Zuckerberg, Charles Koch….and by the way: Vladimir Putin and his ilk, Mohammad bin Salman and his ilk etc.: those guys since long controlling all the COP-meetings, with the known result: a tropospheric CO2-level higher than in at least 23 million years https://pubs.geoscienceworld.org/gsa/geology/article/48/9/888/586769/A-23-m-y-record-of-low-atmospheric-CO2 and the socalled 1,5 degree C “limit” being blown away already next year, see https://www.researchsquare.com/article/rs-6079807/v1

          Reply
          • zebra says

            10 Aug 2025 at 1:35 PM

            Interesting stuff on the development of vertical wind turbine designs I wasn’t aware of.

            I would also mention, WRT “geothermal”, a simple design option which I have used, which is a slab foundation with horizontal perimeter insulation. It’s essentially a basement in terms of it’s thermal performance. In New England winters it requires little heat input, and despite having had the building for 20-odd years, I am surprised every spring/summer at how cool it is on really hot days.

            This is a cheap, passive way to harvest the planet’s thermal energy.

            But obviously there are all kinds of ways to reduce FF consumption, and you are correct that vested interests (at all levels and in all aspects of design and construction) resist them.

            And the problem is of course that we *don’t* have an actual free markets economy, which requires strong government regulation.

          • Tomáš Kalisz says

            10 Aug 2025 at 5:40 PM

            in Re to Karsten V. Johansen, 10 Aug 2025 at 5:38 AM,

            https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837291

            and zebra, 10 Aug 2025 at 1:35 PM,

            https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837304

            Dear Sirs,

            Thank you for your remarks regarding geothermal energy.

            While I appreciate the smart use of a basement as a supporting heat source for heating in winter and as a cold reservoir for air condition in summer, I doubt that geothermal energy exploitation may be a solution on a larger scale.

            Please consider that due to poor thermal conductivity of Earth crust, the average geothermal energy flow is several orders of magnitude smaller than average solar irradiance of Earth surface and can be thus neglected in Earh surface energy balances. Practical consequence of this circumstance are enormous investments necessary for geothermal energy exploitation. Geologically active regions, rich in hot springs like Island, represent an exception.

            Greetings
            Tomáš

      • Ron R. says

        2 Aug 2025 at 10:20 AM

        Narrow gauge. Or maybe some sonic device that would repel birds.

        Reply
        • Ron R. says

          2 Aug 2025 at 2:52 PM

          Or here’s an idea, how about attaching metallic reflective streamers to the blades? It would sparkle and reflect a rainbow of colors. That could detract birds.

          Reply
          • Ray Ladbury says

            3 Aug 2025 at 10:52 AM

            Might attract a lot of Stoners though.

          • Ron R. says

            3 Aug 2025 at 1:05 PM

            Ray Ladbury, ”Might attract a lot of Stoners though.

            Funny

            Didn’t psychedelic go out in the 60s?

          • Ray Ladbury says

            4 Aug 2025 at 2:00 PM

            You know what they say: if you remember the ’60s, you weren’t there. Me, I grew up in the ’70s, the just-say-when generation.

      • BRIAN C DODGE says

        3 Aug 2025 at 5:09 PM

        A 100 meter wind turbine can flex up to 8 meters. If flaps were installed on the blades to alter the lift on the blades and intentionally change the flex, they could be steered to avoid birds tracked by radar. The flaps could also be used to dynamically suppress blade vibration.

        Reply
        • Ron R. says

          5 Aug 2025 at 10:57 AM

          That’s good. We’re thinking! Maybe a single dot painted on a single blade would make it look like something was there? Or an owl with a rotating head on top of the post?

          But like David says, that wouldn’t help with bats or night time migratory flights.

          Reply
      • David says

        4 Aug 2025 at 9:44 AM

        Having a wind farm only a few miles outside of the town I live in has proven to be very useful in exploring informally many of the questions and supposed “facts” surrounding environmental impacts of their operation.

        Bottom line: our wind farm is NOT a bird graveyard. The number of birds killed varies by season, with the largest numbers found in fall and spring, likely associated with migration. Though often overlooked in public discussions, the number of bats killed often equalled or exceeded numbers of avian fatalities here. There’s not been a formal research paper done on this farm, so I am relying on what I’ve seen along with others, including with researchers from one of our state’s universities. The local operators have been easy and helpful to work with, though that’s become more difficult recently after their corporate legal folks got involved (surprise, surprise). Interesting, wild scavenging of carcasses makes it challenging to accurately count; Mother Nature is efficient at not letting anything go to waste, let alone waiting for us humans to get around to counting!

        Stating the obvious, the current federal administration doesn’t give a flying damn about birds, bats or the environment. Regardless how one wants to look at the numbers, wind farms are less negatively environmentally impactful than their fossil-fueled counterparts. Directly and certainly when indirect impacts are considered.

        Of course, if Americans wanted to do something that really would make a huge difference to benefit birds, they could make one simple change as a society. Most current studies show that approximately ONE BILLION birds are killed every year by cats in North America. So keep your cats inside and the feral population needs to be removed, adopted or euthanized. Exceptions for farmers could be made for obvious reasons. But I won’t hold my breath waiting on anything so simple…

        Reply
        • Ray Ladbury says

          4 Aug 2025 at 2:07 PM

          Although windfarms can pose a threat to birds, bats, butterflies…I’d go out on a limb and guess that as many birds die slamming into Trump Tower as into a windfarm. It’s not as if windmill blades are turning very rapidly compared to the speed at which a bird flies. And the cat thing is by far a greater threat–one reason why all our cats are indoor (the other being that it doubles their lifespan).

          Reply
          • Nigelj says

            4 Aug 2025 at 9:19 PM

            RL, buildings in America kill about 600 million birds each year, especially the glass faced buildings. Wind turbines in America kill hundreds of thousands of birds each year so it sounds like you may be right. Cats are the single biggest killer. Courtesy of a quick Google AI evaluation of the available studies. I’ve been involved in high rise building facade design so I was curious.

            But for me the main point is that coal fired power kills about 10 times as many birds per gwhr as wind power according to the source I posted above, so just shifting to wind power is a huge positive greatly reducing bird fatalities. Even if it only halved the number of deaths its a positive. So if Trump is genuinely worried about birds he should be closing coal fired power and building wind farms. Ha ha.

          • Ron R. says

            5 Aug 2025 at 10:42 AM

            I used to have cats, love them, but once a cat goes outside it forever pines to go outside again, it seems. So it seems cruel (to me at least) to keep them inside. They love to sit in the grass or tree branches and snooze.

            So why I have no cats now. :(. Well, the other reasons are related. As we’re talking about here, cats are voracious bird hunters. I like birds too. Have a bird bath outside that they regularly use. All kinds of birds. Drip line fed to keep it clean. Would hate to see those birds targeted. They’d likely stop using it.

            Another reason I don’t have cats now is that I can’t stand litter boxes. No matter how they design them they’re disgusting, smelly, unhealthy things.

            Yeah, birds fly into windows too. I was just hoping that we could come up with some easy, unobtrusive way to make wind farms safer. Would make wind power more publicly attractive too.

            Their size is an issue too for people living near them. They definitely work. No doubt about that. But I prefer solar.

          • Joseph O’Sullivan says

            5 Aug 2025 at 1:32 PM

            The New York City chapter of the Audubon Society (that chapter is now called the NYC Bird Alliance) did a citizen science project where volunteers collected birds killed from building strikes. I checked a building a block south from trump tower and there were dead birds there every morning during migration season. I’m sure trump tower was no different.

          • Pedro Prieto says

            6 Aug 2025 at 12:17 AM

            It’s modeling, statistical extrapolation and not hard counts. Why believe any of it?

          • Ray Ladbury says

            6 Aug 2025 at 8:50 AM

            Pedro Prieto: Why believe any of it?

            Because the assumptions of the model and the data used for it are credible. Statistical reasoning can yield understanding that would not be possible using purely empirical methods. Numbers and data have a structure.

        • jgnfld says

          6 Aug 2025 at 10:43 AM

          Re. “It’s modeling, statistical extrapolation and not hard counts…”

          Try telling this to a casino security guard who has exactly the same sort of evidence you are card counting and see if it stops them from kicking you out on the street.

          Reply
      • Ron R. says

        5 Aug 2025 at 3:41 PM

        My AI says on solar versus wind generation,

        ”One acre of solar power panels generates significantly more electricity than one acre of wind power turbines due to differences in land use efficiency and capacity factors. Solar farms use about 3 acres per gigawatt-hour (GWh) of electricity generated per year, meaning one acre of solar can produce approximately 0.33 GWh annually. In contrast, wind farms require about 26 acres per GWh per year when considering only the area occupied by turbines, translating to roughly 0.038 GWh per acre annually. This makes solar about 8.5 times more efficient per acre than wind in terms of electricity output…. Over time, an acre dedicated to solar can generate 25 GWh of electricity over 75 years, compared to 26 GWh for wind, indicating comparable long-term energy yields per acre when sustained use is considered. Both technologies produce electricity with minimal carbon emissions—around 48 grams of CO₂ per kilowatt-hour for solar and 11 grams for wind—far less than fossil fuels.”

        The provided link,

        https://www.freeingenergy.com/land-usage-comparison-solar-wind-hydro-coal-nuclear/

        About the resources of one acre of solar vs one acre of wind the answer comes back as undetermined. Maybe one of the more knowledgeable here would know.

        Btw, let’s decentralize solar. Instead of further farms, put them on roofs that would stand to benefit, and pay for it by diverting the many billions or collectively trillions of dollars from the war machine. Really, how many (expensive) bombers and bombs do we need every year? C’mon.

        https://www.statista.com/statistics/264434/trend-of-global-military-spending/

        Reply
      • Ron R. says

        5 Aug 2025 at 5:44 PM

        Very sorry for spamming this month. These thoughts occur to me throughout the day, and this is the unforced variations thread. :)

        I want to make a modest proposal to be read and voted upon at the United Nations.

        How many times over do we need to be able to destroy the world?

        A MODEST PROPOSAL

        We, the undersigned representatives of the world’s nations promise to divert all of our military spending, save for that necessary to pay our personnel, for one calendar year starting in fiscal year 2026, for spending on alternative energies, particularly solar power, to be given away to the world’s peoples and thus helping to solve in a large way the dire threat of global warming.

        Reply
  2. Ron R. says

    1 Aug 2025 at 1:31 PM

    “This month’s open thread. Please try and stay focused on substance rather than personalities. There are many real issues that are particularly salient this month, and so maybe we can collectively try not to have the comments descend into tedium.

    Land of Confusion

    https://m.youtube.com/watch?v=pyOla0JQuMg

    The rallying song

    Reply
  3. Susan Anderson says

    1 Aug 2025 at 2:20 PM

    Reposting this BlueSky Andrew Dessler from Endangerment (h/t Philip Clarke)
    Please note: “We are primarily looking for Ph.D. scientists at universities or government labs in appropriate fields. I realize that this will exclude some qualified people and I apologize, but we felt this was necessary for a variety of reasons.”
    https://bsky.app/profile/andrewdessler.com/post/3lvbrnzqmyo27 [good discussion in subcomments]

    DOE Climate Response Form – https://docs.google.com/forms/d/e/1FAIpQLSdwVruhK2TZpTImdk1eDw0En9zEirB5piFU6FFhZhHTIY2q0A/viewform?pli=1

    Reply
  4. E. Schaffer says

    1 Aug 2025 at 3:52 PM

    Does anyone take the Chinese emission figures serious? In 2024 China used about 5Gt of coal. By common metrics this should translate into some 12 to 12.5 Gt of CO2, roughly equating to total Chinese CO2 emissions.

    If I have it right, the story goes like this. In early 2015 some statistics emerge showing China using 17% more coal than previously known and reported. Just afterwards Liu et al 2015 was published in Nature, which, in line with some governmental institutions, claimed Chinese coal simply contained 40% less carbon than the IPCC base assumption.

    Those 40% less is really the key finding of the paper, they also name it in the abstract, and they even show the numbers. While the IPCC assumes an average carbon content of 71.3%, Chinese coal only had 49.9%, thus 40% less. The paper had 24 co-authors and will have been thoroughly peer reviewed by Nature.

    I mean it is like they wanted to make a joke over it. As anyone can tell, 49.9 is just 30% less than 71.3. This can not be an oversight. Also the notion of some kind of Chinese “miracle coal”, low in carbon but rich in energy, is absurd.

    Adding insult to injury, the paper points out two “consequences” of its finding.
    a) as Chinese emissions actually had been overestimated, it would only be fair for China to emit more CO2 in the future
    b) otherwise it “implies a considerable (downward) revision of the global carbon budget” because weaker than thought CO2 sinks, meaning less emissions for everyone else

    As strange as it is, those implausibly low emissions from Chinese coal usage are to this day the basis for Chinese emission figures. And if they were not true, we would be missing out a couple of Gt of CO2 p.a.

    Reply
    • Kevin McKinney says

      1 Aug 2025 at 6:05 PM

      E. Schaffer, are you talking about this “Liu et al (2015)”? https://www.nature.com/articles/nature14677 It does have, as you specified, 24 co-authors and was of course published in Nature. There’s a preprint PDF here: https://www.repository.cam.ac.uk/bitstream/handle/1810/253430/Liu%20et%20al.%202015%20Nature.pdf

      Googling “types of coal” found the following four types of coal:

      Peat: “less than 40-55% carbon”
      Lignite (“Brown coal”): 40-55% carbon
      Bituminous coal (“Soft coal”): 40-80% carbon
      Anthracite (“Hard coal”): 80-90% carbon

      Liu et al found that:

      The mean total carbon content of raw coal samples from 4,243 state-owned Chinese coal mines (which 4,243 mines represent 36% of Chinese coal production in 2011 is 58.45%, and the production-weighted total carbon content is 53.34%.

      That hardly seems suspicious, let alone incredible.

      Reply
      • Ray Ladbury says

        3 Aug 2025 at 10:55 AM

        Most of China’s deposits are low-grade bituminous and lignite. It is one of the reasons why steel-making in the Great Leap Forward failed.

        Reply
  5. John Pollack says

    1 Aug 2025 at 10:05 PM

    Tomáš, this is in response to your posting on 31 Jul 2025 at 5:41 pm

    The original vegetation of the western section of the corn belt was prairie, except for areas along streams and bodies of water. Going eastward, the proportion of forested land increased to become mostly forest in Ohio and Indiana. The hydrology of the region was severely altered even in the early to mid 1800s, before most of it was converted to cropland, by the killing of over 100,000,000 beavers. (Most of the pelts were exported to Europe in the fur trade.) There have been many other alterations since.

    I don’t think the contribution of irrigation to water vapor would turn out to be a strong factor in heat waves. In general, it is only the western edges of the corn belt in Nebraska and the Dakotas where irrigation is widely practiced. Groundwater is being rapidly depleted in much of the irrigation zone.

    If the ground and most vegetation were dry before a heat wave started, the overall effect would be to produce more extreme temperatures – especially daytime – and increase the duration of heat waves. However, the factors entering into the creation and maintenance of heat waves are complex. I give
    links to four references, if you want some further reading. I haven’t read these recently, so I won’t be able to comment on their content in detail.

    http://www.nature.com/articles/s41561-019-0431-6
    http://www.nature.com/articles/ngeo1590
    https://journals.ametsoc.org/view/journals/clim/31/12/jcli-d-17-0515.1.xml
    https://journals.ametsoc.org/view/journals/clim/30/7/jcli-d-16-0436.1.xml

    Reply
    • Tomáš Kalisz says

      3 Aug 2025 at 2:37 PM

      In Re to John Pollack, 1 Aug 2025 at 10:05 PM,

      https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-836805

      Hallo John,

      Many thanks for your kind reply and particularly for the references (for which I will definitely need some time, too).

      The remark regarding beavers is also very interesting. I can only guess that also in Europe, beaver population had been drastically reduced in the past (in some regions perhaps already a few thousand years ago), prior or during the landscape conversion towards agricultural land use. I am curious if this specific example of a possibly tight relationship between ecosystems and climate regulation has been already explored.

      Greetings
      Tomáš

      Reply
  6. Victor says

    2 Aug 2025 at 9:13 AM

    My contention that industrial aerosols could not have been a factor in the 40 year mid-century cooling seems to have had no impact whatever here or anywhere else. It’s generally assumed that the implementation of strict anti-pollution controls in Europe were responsible for the abrupt rise in global temperatures from 1979-1998. And recently we’re hearing from several sources that the more recent implementations of such controls on the part of China and other countries present a growing danger that temperatures will rise precipitously once the cooling effect of such pollutants is removed completely.

    In the light of the notion that such aerosols had such a powerful cooling effect as to totally offset the expected mid-century warming, and subsequent pollution controls produced the dramatic warming we see in the following years, I will offer a modest proposal. Why not cancel those controls, permitting the pollutants to once again cool the planet and save us from the “existential threat” posed by rising CO2 levels. Any rise in such levels will automatically be offset by rising aerosol levels. Climate crisis over!

    Reply
    • Tomáš Kalisz says

      2 Aug 2025 at 7:22 PM

      In re to Victor, 2 Aug 2025 at 9:13 AM,

      https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-836818

      Dear Victor,

      The first sentence in your post raises my feeling that you completely missed my reply of 18 Jul 2025 at 8:41 PM,

      https://www.realclimate.org/index.php/archives/2025/07/unforced-variations-july-2025/comment-page-2/#comment-836083

      as well as MA Rodger’s reply of 18 Jul 2025 at 8:56 AM,

      https://www.realclimate.org/index.php/archives/2025/07/unforced-variations-july-2025/comment-page-2/#comment-836046

      which I see quite instructive, especially in view of my further exchange with MA Rodger:

      19 Jul 2025 at 6:28 AM,

      https://www.realclimate.org/index.php/archives/2025/07/unforced-variations-july-2025/comment-page-2/#comment-836101 ,

      19 Jul 2025 at 3:08 PM,

      https://www.realclimate.org/index.php/archives/2025/07/unforced-variations-july-2025/comment-page-2/#comment-836116 ,

      20 Jul 2025 at 5:24 PM,

      https://www.realclimate.org/index.php/archives/2025/07/unforced-variations-july-2025/comment-page-2/#comment-836171 .

      As regards your proposal that the observed global warming could be mitigated simply by returning to fossil fuel consumption without measures against sulfur dioxide emissions, there are at least two good reasons why it may not be a good idea:

      1) You perhaps may have heard about negative effects of sulfur dioxide emissions and aerosol pollution on human health

      https://en.wikipedia.org/wiki/Great_Smog_of_London

      and on ecosystems

      https://en.wikipedia.org/wiki/Acid_rain .

      2) In a more sophisticated form of your proposal, there are suggestions that such negative “side effects” of the “aerosol geoengineering” can be avoided if sulfur dioxide will be injected from aircrafts directly into stratosphere.

      This idea is pushed by a respective business lobby, however, it has also at least one significant pitfall:

      There is a solid theoretical evidence, see

      https://idw-online.de/de/news564976 and further references on this webpage

      that although this kind of “mitigation” (of the rising greenhouse effect by increasing Earth albedo) could indeed stabilize Earth surface temperature, there will be a price therefor, in weakening of global water cycle.

      Nobody knows the consequences of such an enterprise yet. It is not excluded that the price may be significant, e.g. in form of desertification of entire continents.

      Best regards
      Tomáš

      Reply
    • Ray Ladbury says

      3 Aug 2025 at 10:56 AM

      Really, who cares what your contention is. Your credibility has been burned so many times over, even the ash has scorch marks.

      Reply
    • Barton Paul Levenson says

      3 Aug 2025 at 1:59 PM

      V: My contention that industrial aerosols could not have been a factor in the 40 year mid-century cooling seems to have had no impact whatever here or anywhere else.

      BPL: Imagine that! I wonder why?

      Reply
    • Thessalonia says

      8 Aug 2025 at 2:19 AM

      Reply to Victor
      My contention that industrial aerosols could not have been a factor in the 40 year mid-century cooling seems to have had no impact whatever here or anywhere else. It’s generally assumed that the implementation of strict anti-pollution controls in Europe were responsible for the abrupt rise in global temperatures from 1979-1998. etc

      Tessa:
      You’ll never get a straight answer here Victor let alone an acknowledgement that a single query you make is credible and valid. I cannot satisfactorily respond either, but what I will say is that I think it’s worth keeping one eye on what comes from Hansen et al team of climate scientists in the coming years.

      Here’s one small example from his latest article, in the appendix, as it directly relates to your interest notes above. His framing of the title is equally spot on.
      Regards

      https://www.columbia.edu/~jeh1/mailings/2025/ForestTrees.06August2025.pdf
      pg 11-12-13

      The upshot is that changes of Earth’s radiation balance in the past 25 years, including changing
      albedo and changing LWOUT, are inconsistent with zero or small cloud feedback (gcl = 0-0.1),
      instead favoring large cloud feedback (gcl = 0.2-0.25), which corresponds to climate sensitivity
      4.0-4.8°C for doubled CO2. Based on this, and on the estimates from paleoclimate and
      temperature change since 1850, we infer climate sensitivity 4.5°C ± 1.0°C (2σ).
      12

      A3. Global temperature prior to 1970. GHG forcing has likely increased monotonically
      because of the long lifetimes of the major GHGs, but the balance between aerosols and GHGs
      has oscillated. Our best indicator of aerosol forcing is global emission of SO2 (Fig. 3), which is
      known from knowledge of the sulfur content of fossil fuels (SO2 gas resulting from fossil fuel
      burning is a precursor of the dominant human-made aerosols, sulfates). Fossil fuel use increased
      exponentially during the industrial revolution until 1910, so even though GHGs were beginning
      to accumulate in the air, cooling by aerosols likely exceeded warming by GHGs. During 1910-
      45, due to world wars and weak economies, the growth of fossil fuel use slowed. Because
      aerosol forcing depends on current emissions, while the GHG forcing grows as the long-lived
      gases accumulate, the GHG warming tended to win out during 1910-45, as aerosol emissions
      were almost stagnant. During 1945-1970, exponential growth of emissions resumed, which
      probably accounts for a near balance of GHG warming and aerosol cooling during 1945-70.

      GCM research groups work hard to improve their models between each successive IPCC report,
      submitting model runs to the accompanying Climate Model Intercomparison Projects (CMIPs).
      CMIPs are often described as beauty contests, as each group hopes that their model compares
      well with the real world. A principal model test is whether it can simulate the rate of global
      warming during the period of rapid climate change, i.e., since 1970.
      For decades, most climate
      models had simple cloud models or just “parameterizations” of cloud effects, such that clouds
      13
      had only a small effect on simulated climate sensitivity. The common climate model sensitivity
      was in or near the range 2.5-3.5°C for doubled CO2 (see, e.g., the most recent IPCC report).5 A
      GCM with such climate sensitivity can match observed global warming since 1970 with little or
      no contribution from changing aerosol forcing
      . Although cloud modeling in GCMs remained
      primitive for decades, recent research41,42,43 provides insights consistent with clouds contributing
      substantially to high climate sensitivity, as described in Sidebar 4 of Paper 2

      ===================================

      Sidebar 4. CMIP (Climate Model Intercomparison Project) studies are carried out prior to and in conjunction with IPCC reports, with corresponding numbering. Zelinka et al. (2021)50 show that increased equilibrium climate sensitivity (ECS) of CMIP6 models is primarily due to differences in simulated shortwave (shortwave refers to solar radiation, as opposed to longwave terrestrial heat radiation) low-cloud feedbacks at middle and high latitudes in the Southern Hemisphere (Figure S4a).

      CMIP6 models have a stronger positive low-cloud feedback at midlatitudes in the Southern Hemisphere and a weaker negative low-cloud feedback at high latitudes; both features contribute to higher ECS in many CMIP6 models and in the average of all CMIP6 models.

      Jiang et al. (2023) Footnote26 show that CMIP6 models with higher ECS produce a realistic seasonal cycle of extratropical low clouds with peaks in the austral (southern hemisphere) and boreal (northern hemisphere) winter seasons, while models with lower ECS produce low-cloud seasonal cycles with unrealistic peaks in summer (Figure S4b). The greater skill of high ECS models in simulating cloud variability and cloud feedbacks, especially in the Southern Ocean region, suggests greater confidence in the higher ECS models. Cloud changes are the cause of higher sensitivity in high-ECS models, and thus the observed cloud seasonality provides significant support for high ECS.

      Finally, Williams et al. (2020)Footnote27 tested two alternative cloud configurations in the UK Met Office Unified Model used for weather predictions, finding that the more recent cloud parameterization scheme increases simulated ECS by 2.2 °C, improves the short-range weather forecast, and reduces the error growth over the first few hours of the forecast, indicative of more realistic modeling of local physical processes. These several works indicate that high ECS models are more skillful in simulating cloud feedbacks, a crucial factor in determining real-world ECS.

      https://www.tandfonline.com/doi/full/10.1080/00139157.2025.2434494#d1e558

      Reply
  7. Tomáš Kalisz says

    2 Aug 2025 at 9:16 AM

    In Re to Barry E Finch, 1 Aug 2025 at 12:21 PM,

    https://www.realclimate.org/index.php/archives/2025/07/unforced-variations-july-2025/comment-page-2/#comment-836771

    Dear Barry,

    Many thanks for your kind feedback.

    The idea that water in the ocean behaves analogously as mercury in a thermometer bulb was mentioned, more-less by the way, by Dr. Benestad in a discussion under one of his Real Climate articles which I, unfortunately, cannot properly remember / find / identify anymore.

    You are right that abrupt sea level changes like Lake Agassiz runoff do not reflex any equivalent abrupt Earth energy imbalance (EEI) change. Yet I think that the corresponding sea level rise might have somehow characterized the excess heat accumulated from the EEI during a period of previous ice thawing.

    It is clear that (similarly as for many other paleoclimate proxies) also the relationship between EEI and sea level is not straightforward, because it comprises contributions from at least two different processes, namely from ocean volume thermal expansion / contraction and from changes in land ice volume. I can also imagine a third contribution, from natural changes in terrestrial underground water reserves caused by changes in water cycle intensity and/or in land/sea precipitation distribution.

    Although a past EEI reconstruction based on seal level changes can represent a huge challenge because it would definitely require a complex (and likely quite laborious) analysis, I still find the idea presented by Dr. Benestad appealing and hope that, finally, someone (a collaboration?) will explore it in sufficient detail to apply it successfully.

    Greetings
    Tomáš

    Reply
  8. b fagan says

    2 Aug 2025 at 10:50 PM

    I found this history of the what, when and why of Earth’s climate, recently published in Science News, was very well done.

    How hot can Earth get? Our planet’s climate history holds clues
    A tour through the planet’s past suggests the ways life will survive global warming — or not
    By Elise Cutts – July 17, 2025 at 9:00 am

    https://www.sciencenews.org/article/climate-change-history-earth-warming

    Anyone unfamiliar with the kind of science jargon we all are used to encountering here should be able to get a grip of “earth’s climate history for non-dummies” from this piece (I think Potholer54’s done something similar in one of his videos, but this is current and should be shared).

    Reply
  9. Victor says

    3 Aug 2025 at 8:58 AM

    Tomáš Kalisz says:

    As regards your proposal that the observed global warming could be mitigated simply by returning to fossil fuel consumption without measures against sulfur dioxide emissions, there are at least two good reasons why it may not be a good idea:

    1) You perhaps may have heard about negative effects of sulfur dioxide emissions and aerosol pollution on human health

    https://en.wikipedia.org/wiki/Great_Smog_of_London

    and on ecosystems

    https://en.wikipedia.org/wiki/Acid_rain .

    V: Yes of course. However, the world managed to get along pretty well in the many, many years before anti-pollution measures were implemented. Yes, industrial aerosols are unhealthy, but they are far from constituting the “existential threat” posed by “climate change.” Just think. No more floods, no more drought, no more wildfires, no more sea level rise, no more “rain bombs,” no more heat waves, etc., etc. A certain amount of pollution would be a small price to pay if all these “existential threats” and the many tipping points associated with them could be averted — with little to no cost.

    Smokestacks could be extended in length. People could once again resort to wearing masks, as during the Covid crisis. The world learned to live with pollution for a great many years and the great majority managed to survive in good health.

    TK: 2) In a more sophisticated form of your proposal, there are suggestions that such negative “side effects” of the “aerosol geoengineering” can be avoided if sulfur dioxide will be injected from aircrafts directly into stratosphere.

    V: That’s a terrible idea. For one thing it would require fleets of aircraft flying high in the stratosphere continually, year after year for the foreseeable future, belching yet more CO2 as they flew. Who could pay for that? And of course no one knows what the effect would be on the world’s climate — possibly producing cold spells, endangering crops, etc. No, the effects of uncontrolled pollution are already well-known, and we can cope with them, as we have in the past.

    Reply
    • Barton Paul Levenson says

      3 Aug 2025 at 2:01 PM

      V: the world managed to get along pretty well in the many, many years before anti-pollution measures were implemented.

      BPL: London, 1952–4,000 dead.

      Reply
      • Victor says

        4 Aug 2025 at 2:58 PM

        Yes, the Great Smog of London was certainly a major disaster. See https://www.youtube.com/watch?v=wiHd9Ah4CQA&t=13s

        Yet it was a one-time event. As the video states, “normally winds blew the smoke away.” Which is not to say that such pollution doesn’t always present health risks.

        However, according to the alarming warnings we hear continually from so many climate scientists, the risks of fossil fuels heating the Earth to ever more alarming degrees are far greater. Despite so many attempts to reign it in, year after year, since the 70’s, ever greater amounts of CO2 are still entering the atmosphere with no end in sight.

        As seems clear, there would seem no way to abate this “existential threat” without devastating the world’s economy, depriving millions of affordable power, heat and transportation, fertilizer, and plastic-based commodities. Whether or not you go along with this assessment, you have to agree that fossil fuels are not going away any time soon.

        Certain desperate climate change advocates are now proposing extremely costly and dangerous “fixes” such as the seeding of the stratosphere with aerosols, intended to reflect the sun’s rays up and away, thus cooling the planet. As there is no way to predict the effects of such measures, they are clearly a bad idea that could have devastating unintended consequences (in addition to being totally impractical, as the planes doing the seeding would need to be aloft almost continuously for the indefinite future, at an untenable cost.)

        Given all the above, it seems to me that, if you truly believe industrial aerosols have a cooling effect sufficient to counter the warming effect of CO2, permitting them to once again freely pollute the atmosphere represents what may be our only hope. It’s a trade-off for sure – what Hansen, in a somewhat different context, has referred to as “a Faustian bargain,” But for those of us who’ve managed to convince ourselves that the unabated burning of CO2 will inevitably ravage the Earth and just about every living thing on it, the opportunity to totally mitigate this problem at little to no (economic) cost is, as I see it, a no-brainer.

        Reply
        • John Pollack says

          4 Aug 2025 at 8:06 PM

          Victor,

          We can always count on you to propose the no-brainer solutions.

          Has it occurred to you that your “solution” would require producing rising levels of industrial aerosols to counteract steadily rising CO2 levels, yet that production would keep pushing up CO2 further?

          Reply
        • Barton Paul Levenson says

          5 Aug 2025 at 7:47 AM

          V: Yes, the Great Smog of London was certainly a major disaster. . . . Yet it was a one-time event.

          BPL: Donora, PA 1948. 20 dead, 6000 injured.

          Reply
        • Kevin McKinney says

          5 Aug 2025 at 4:42 PM

          Victor wrote:

          As seems clear, there would seem no way to abate this “existential threat” without devastating the world’s economy…

          Wrong again. There are quite a few published papers examining this very question, and finding quite the reverse. We’ve talked about many of them here. And in fact, fossil fuels aren’t very competitive for power generation any more:

          https://www.irena.org/News/pressreleases/2025/Jul/91-Percent-of-New-Renewable-Projects-Now-Cheaper-Than-Fossil-Fuels-Alternatives

          Name a country or region, and chances are IRENA has a ‘roadmap’ for doing just what Victor claims without evidence to be impossible. Indonesia, for example, to take one very large, rapidly growing developing nation:

          https://www.irena.org/-/media/Files/IRENA/Agency/Publication/2022/Oct/IRENA_Indonesia_energy_transition_outlook_2022.pdf

          Reply
          • Pedro Prieto says

            6 Aug 2025 at 12:39 AM

            If this was true, then how does South Australia have one of the most expensive electricity tariffs in the world?

            South Australia (SA) is a leader in renewable energy, with over 70% of electricity generated from wind and solar, projected to reach 85% by 2026 and 100% by 2027. SA often imports electricity from eastern states, especially Victoria, across the broader National Electricity Market (NEM). Despite its high renewable share, it remains a net importer in most years since 2021

            Eastern Australia (e.g. NSW, VIC, QLD) The eastern grid is heavily interconnected across multiple states, making it more resilient and liquid. It has more stable generation capacity (coal, gas, hydro), <b<with lower average wholesale prices than SA—SA prices are typically ~30–40% higher due to storage and grid constraints

            Real world vs theory?

            Spain is a little different. Spain has a high level of renewable energy penetration—around 57–59% of electricity demand. But household electricity prices remain moderate (~€0.24/kWh), below the EU average and considerably lower than in high-RE EU nations such as Germany or Denmark.

            Spain’s experience shows that massive renewables uptake does not automatically mean prohibitive electricity bills, particularly when grid fees and tax burdens are managed efficiently. The question is, is it sustainable long term-re international interconnector charges?

            Denmark ~88% ~€0.38 High price from taxes, not generation cost
            Germany ~40–50% ~€0.39 Similar structure with high levies

          • prl says

            6 Aug 2025 at 7:33 PM

            South Australia does indeed have the highest average electricity prices in Australia, AUD0.4465/kWh.

            That currently converts to about €0.25/kWh, only slightly above the price you give for Spain, and considerably below the prices you quote for Denmark and Germany.

            The Australian Capital Territory, where I live, has an average electricity price of AUD0.3216/kWh, or about €0.18/kWh. The ACT has 100% net zero electricity supply.

            The Australian prices are inclusive of 10% GST (VAT).

            https://www.finder.com.au/energy/electricity/average-cost-of-electricity
            Currency conversions by Google.

          • Thessalonia says

            6 Aug 2025 at 11:51 PM

            prl-The ACT has 100% net zero electricity supply?

            Falls into the cherry-picked irrelevant wrong category. :-)

            Australian Capital Territory (ACT) is often cited as having achieved 100% renewable electricity (not net zero electricity supply — a different concept), and this claim is based on several unique mechanisms and contextual factors:

            Important Distinctions:
            100% renewable electricity ≠ 100% net zero emissions overall.
            The ACT still has emissions from transport, heating, buildings, and consumption.
            The electricity claim applies only to scope 2 electricity use, not scope 1 direct emissions or scope 3 embedded emissions.

            Key Reasons ACT Achieved 100% Renewable Electricity:
            1. Reverse Auctions and Long-Term Contracts (PPAs)
            The ACT government used reverse auctions to contract wind and solar farms across Australia (mostly outside the ACT).
            These contracts provide certificates and renewable energy credited against ACT consumption.
            It’s not that the electrons powering the ACT are all renewable — it’s an accounting-based offset model.

            2. Generous Feed-In Tariffs and Solar Incentives
            The ACT offered some of Australia’s best feed-in tariffs for residential solar in the 2010s.
            This accelerated rooftop solar uptake despite the ACT’s relatively small size and modest solar resource (compared to QLD or SA).

            3. Small and Urbanized Population
            The ACT has a relatively small population (~460,000) and concentrated energy demand in Canberra. (or a tightly concentrated grid area)
            Easier to meet total demand through contractual renewable energy generation elsewhere.

            4. Grid Connection and Import Reliance
            The ACT is fully grid-connected to NSW, and imports almost all its electricity physically.
            The 100% figure reflects contractual purchases, not local generation.
            Actual physical supply still includes coal and gas electrons — but the ACT purchases enough renewable generation to offset 100% of its use.

            5. Political Will and Policy Consistency
            The ACT has had stable, climate-progressive governance, allowing for long-term clean energy planning.
            The ACT Climate Change and Greenhouse Gas Reduction Act 2010 set binding targets early and was backed by sustained policy.

            If everywhere wanted to be like the ACT there would not be enough RE WWS +Storage supply in external grid jurisdictions to ‘Contractually Offset’ all the FF Electricity consumption.

          • prl says

            9 Aug 2025 at 10:11 PM

            100% renewable electricity ≠ 100% net zero emissions overall.
            The ACT still has emissions from transport, heating, buildings, and consumption.

            All correct. But I never claimed otherwise.

        • Ron R. says

          9 Aug 2025 at 7:40 AM

          •devastating the world’s economy,”

          I think you’ll find the worlds economies will fare MUCH BETTER once we stop shoveling ALL THIS MONEY at one, fat, filthy,, Model-T like pig, stop trying to stop progress, and get with a future of clean alternative energies.

          I’ve always operated under the maxim that if there’s something which I KNOW that, sooner or later, I’m going to HAVE to do I might as well do it NOW . Every day, week, month or year until then is simply wasted time.

          Do the right thing – show that you care about the future.

          Reply
          • Ron R. says

            9 Aug 2025 at 11:58 AM

            “In 2022, U.S. consumers spent $1.7T on energy, or 6.7% of GDP.1 Annual energy costs were $5,159 per person, a 30% increase from 2021.1 ”

            https://css.umich.edu/publications/factsheets/energy/us-energy-system-factsheet#references

            https://www.eia.gov/state/seds/seds-data-complete.php?sid=US#PricesExpenditures

            And that’s only Americans. No wonder the FF industry is loath to give that up!

            Americans have to use the stuff now because cause that’s all most can afford, thanks to Republicans.

            Cmon, let’s do the right thing for once can we?
            Let’s put that money back in their pockets.

    • Tomáš Kalisz says

      3 Aug 2025 at 2:10 PM

      In Re to Victor, 3 Aug 2025 at 8:58 AM,

      https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-836870

      Dear Victor,

      You are, of course, right that the return to sulfur-rich fuels could be attempted. I even think that e.g. in marine transport, there would have been practically no harm for human health (no need for masks), although I do not know how serious the influence of a such retreat from introduced regulations on marine ecosystems can be.

      Nevertheless, I still doubt that it would be a sustainable solution. I am afraid that slowing water cycle down can be indeed an unavoidable consequence. If so, basically any atempt to stabilize the radiative energy balance of Earth by making the atmosphere opaquer for incoming solar radiation may be even more harmful than the unmitigated temperature rise.

      I therefore rather prefer step-by-step replacement of fuels with electricity from renewable energy sources wherever it is technically and economically advantageous. Based on (in my opinion huge) unexploited technical potential for cheap electricity storage that can expand the scope for economically competitive use of energy from renewable sources significantly, I see this way towards climate change mitigation economically and societally more feasible and thus more promising than your proposal.

      Best regards
      Tomáš

      Reply
    • Christopher Judd says

      5 Aug 2025 at 12:08 PM

      V: “Why not cancel those controls, permitting the pollutants to once again cool the planet and save us from the “existential threat” posed by rising CO2 levels.”

      CJ: They weren’t cooling the planet, they were slowing the rise in temperatures. As the GHG levels increase, the aerosol effect would be smaller relative to the heating. Have you calculated how much aerosol sulfate that the atmosphere will hold, given rainout and dry deposition? Is that enough to offset GHGs?

      V: ” …the world managed to get along pretty well in the many, many years before anti-pollution measures were implemented.

      CJ: “The WHO estimates that there are 7 million deaths annually from air polution. Granted, these are not all from burning fossil fuels, but a large percentage of them are. Increasing FF usage will result in millions of more unnecessary deaths each year. Not to mention the morbidity effects, and the impact on ecosystems and infrastructure.”

      Reply
      • Victor says

        9 Aug 2025 at 1:43 PM

        CJ: They weren’t cooling the planet, they were slowing the rise in temperatures. As the GHG levels increase, the aerosol effect would be smaller relative to the heating.

        V: According to the mainstream view (presumably your view), the cooling effects of those aerosols were sufficient to negate the expected warming produced by the burning of fossil fuels during the 40 years of 1940-1979. If they could have that effect then, I see no reason why they couldn’t have that effect on later instances of fossil fuel burning.

        In other words, according to YOUR (not my) view of what happened mid-20th century, unhindered aerosols produced by burning fossil fuels would be powerful enough to negate the warming produced by that same procedure. Which is exactly what you and so many others are crying for. There is no reason to assume “the aerosol effect would be smaller relative to the heating.” The more CO2 produced, the more aerosols would be produced. Simple.

        Reply
  10. MA Rodger says

    3 Aug 2025 at 9:46 AM

    CherylJosie,
    I continue my response to your rather lengthy comment of 25th July which is mainly reflecting on the “omissions” & “inclusions” of Goessling et al (2024). Here I make reply to the middle bit between the two “continuing”s.

    There are rather too many singular observational comments/speculations in this middle bit to discuss or investigate them all. I will consider just two of them.
    And thirdly there is also a graphic lurking on a linked Bluesky thread throwing light on previously announced-unexplained “the data and mechanisms” back in the June UV thread.

    (1) This first one is rather nerdy concerns the Indian Ocean area with the large-&-strong 2023 albedo anomaly (as in Fig 1a of Goessling et al 2024).
    This ‘low albedo’ area is actually two areas close together (centred on 95E,5S & on 80E,12S respectively).
    The first check is that this is a 2023 thing and not a longer-term event of ‘low albedo’, and if it is, has it happened in other years.
    The CERES data shows it is a 2023-thing and both areas showed similar ‘low albedo’ anomalies in 2006 & 2019. Perhaps the biggest ‘tell’ of their similarity is that these are by far the biggest ‘potholes’ in the albedo record (actually the OSR not albedo) of the first area and all centred on October of these years. The second area pothole is less defined and it also has a fourth pothole (2016) which coincides with an upward albedo wobble in the first area. The first area also has coincidental 2006, 2019 & 2023 potholes in the temperature record.
    Make of that what you will. Any role of Rossby waves is not a climate mechanism I know much about

    (2) You talk of “rapid loss of sea ice during Antarctic winters that first showed up in January of 2022” (à la Hunga Tonga) but I don’t think the Antarctic SIE plays ball with such an assertion. (Note January is the height of the Antarctic summer.) The annual melt-freeze cycle does rather hide the dramatic variations in SIE (at either pole) and neither the NSIDC CHArctic tool nor the JAXA Vishop tool provide a plot without the annual cycle. That requires a bit of DIY. The JAXA daily Antarctic SIE anomalies are plotted out HERE – Graph 3b and homing-in on the last five years, see the graphic HERE – Posted 3rd August 2025. Clearly nothing is happening in January 2022.

    (3) The graphic lurking on the Bluesky thread is a pretty adventurous effort. It firstly presents (presumably ER5) SST 60N-60S data 1979-to- March 2025 with a whole bunch of climate oscillations (ENSO, PDO, IOD, NPGO, AMO) “subtracted out.” These adjusted data are then annotated showing periods of volcanism and thus illustrating resulting potential deviations of the 60:60SST from a “model” SST trend line. The graphic also plots (the RH scale) some estimate SO2 and WV(SO2eq) ejections from this volcanism. Some of these eruptions don’t feature in any climatology I’ve seen, the full list comprising:-
    … St Helens 1980 (VEI-5)
    … Vulkan Alaid 1981 (VE-4)
    … North Pagan 1981 (VE-4)
    … El Chichón 1982 (VEI-5)
    … Home Reef 1984 (VEI-3)
    … Pinatubo 1991 (VEI-6)
    … Hunga Tonga 2009 (VEI-2)
    … Nabro 2011 (VEI-4)
    … Hunga Tonga 2022 (VEI-6)
    The potential Hunga Tonga impact on 60:60SST is shown suggesting the anomaly will tend toward the “model” value without dropping below that of March 2025. And in the last 4 months that is what has happened.

    CherylJosie, your question back on the June VU thread was “Have I left a thick enough trail of breadcrumbs, or am I following a dead end of a defective self-styled model?” The “trail of breadcrumbs” does remain too thin.
    The method of adjustment used on the 60:60SST numbers does, at a minimum, need describing. Presumably it isn’t a problem but it would have to be reproduced by others. Likewise the “model” SST trend line needs explaining.
    In terms of the attribution of any deviations of the adjusted 60:60SST anomalies, there is measurement of stratospheric water vapour post-2004 so the 2009 Hunga Tonga attribution can at minimum be checked against such measurements, if the data can be sourced in a suitable form. (So the daily graphics etc HERE would take a bit of work.)

    I will cast my jaundiced eye oner the remainder of the 25th July UV comment in due course.

    Reply
    • FitzhenryO'R says

      4 Aug 2025 at 8:10 PM

      Reply to MA Rodger ………………. the Great Smog of London was certainly a major disaster. See https://www.youtube.com/watch?v=wiHd9Ah4CQA&t=13s

      Yet it was a one-time event. As the video states, “normally winds blew the smoke away.” Which is not to say that such pollution doesn’t always present health risks.

      However, according to the alarming warnings we hear continually from so many climate scientists, the risks of fossil fuels heating the Earth to ever more alarming degrees are far greater. Despite so many attempts to reign it in, year after year, since the 70’s, ever greater amounts of CO2 are still entering the atmosphere with no end in sight.

      As seems clear, there would seem no way to abate this “existential threat” without devastating the world’s economy, depriving millions of affordable power, heat and transportation, fertilizer, and plastic-based commodities. Whether or not you go along with this assessment, you have to agree that fossil fuels are not going away any time soon.

      Certain desperate climate change advocates are now proposing extremely costly and dangerous “fixes” such as the seeding of the stratosphere with aerosols, intended to reflect the sun’s rays up and away, thus cooling the planet. As there is no way to predict the effects of such measures, they are clearly a bad idea that could have devastating unintended consequences (in addition to being totally impractical, as the planes doing the seeding would need to be aloft almost continuously for the indefinite future, at an untenable cost.)

      Given all the above, it seems to me that, if you truly believe industrial aerosols have a cooling effect sufficient to counter the warming effect of CO2, permitting them to once again freely pollute the atmosphere represents what may be our only hope. It’s a trade-off for sure – what Hansen, in a somewhat different context, has referred to as “a Faustian bargain,” But for those of us who’ve managed to convince ourselves that the unabated burning of CO2 will inevitably ravage the Earth and just about every living thing on it, the opportunity to totally mitigate this problem at little to no (economic) cost is, as I see it, a no-brainer.

      Reply
      • Tomáš Kalisz says

        6 Aug 2025 at 9:44 AM

        in Re to FitzhenryO’R, 4 Aug 2025 at 8:10 PM,

        https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-836988

        Sir,

        In the year 1989, the “socialist” Czechoslovakia, wherein I grew up, mined and consumed almost 100 million tons of brown coal comprising up to 2% sulfur by weight. Thus, annual sulfur dioxide emissions from burning this fuel then accounted about 4 million tons.

        Forests in the Ore Mountains nearby the biggest Czech power plants were almost completely destroyed by acid rains. During autumn inversions, people in the industrial region of the North Bohemian Coal Basin suffocated quite analogously as in London 1952. In November 1989, the situation led to protests in the regional centre Teplice that became one of the last impulses to the “velvet revolution” a few days later.

        Keeping this experience in mind, I do not think that your proposal is reasonable / feasible.

        Best regards
        Tomáš

        Reply
  11. b fagan says

    3 Aug 2025 at 6:45 PM

    Just noticed this June article in EL PAÍS and wonder if any climate modeling experts could weigh in on what might change in their job and model outputs if this pans out. The researcher they interview is at Brown.

    “Spanish mathematician Javier Gómez Serrano and Google DeepMind team up to solve the Navier-Stokes million-dollar problem”

    https://english.elpais.com/science-tech/2025-06-24/spanish-mathematician-javier-gomez-serrano-and-google-deepmind-team-up-to-solve-the-navier-stokes-million-dollar-problem.html

    Reply
    • MA Rodger says

      4 Aug 2025 at 4:19 AM

      b fagan,
      Assuming you refer to the consequences of an AI-assisted solution to Navier-Stokes (rather than the prospect of AI running riot through science generally and climate models in particular): assuming this, there are perhaps two questions you raise.

      (1) Would the use of an approximation of Navier–Stokes in climate modelling benefit from more exact treatment?
      To be clear, GCMs do employ Navier-Stokes although at what level (& thus any benefit from a more exact treatment) of the simulation process is a bit beyond my paygrade.

      (2) Is the rough probability of these ‘singularities’, these “tsunami in a calm sea”-type events that Navier-Stokes apparently predicts (but which are absent from the approximations) probable-enough to be of climatological concern?
      I note the article you link-to appears to answer the second of these questions in the affirmative, telling us “these equations are essential for predicting phenomena as relevant as the weather, catastrophic floods, the movement of an airplane, or blood flow in a human being.” [my bold] Yet I do wonder if this statement has derived its list of “essential” uses from the longer list of optional and “helpful” uses of Navier Stokes presented by Wikkipedia.

      Reply
      • Jonathan David says

        4 Aug 2025 at 12:44 PM

        MA Roger
        Unfortunately the article referenced by b fagan throws a bunch of complicated ideas together that may result in confusion.

        The study of Partial Differential Equations is of interest to both pure and applied mathematicians The Clay prize relates to the mathematical study of the Navier Stokes equations in which questions of the nature of solutions are sought namely existence, uniqueness and other properties such as smoothness and boundedness. So it’s more about which solutions are possible than approximating them in any way.

        The Navier Stokes equations are themselves an approximation of reality. This approximation can break down in singular solutions such as shock waves. Similarly, climate models, as I understand them, rely on traditional numerical approximation schemes such as spectral or finite difference methods which are imperfect approximations to NS which is itself an imperfect approximation to reality,

        So if the question is if the solution of the Clay prize is relevant to climate modeling I can’t see how.
        If the question is whether using AI or physics-informed neural networks might be the basis for better physical modeling the answer is likely yes. If the question is do singular solutions of NS have physical relevance to climate modeling I would think this would be unlikely.

        Reply
        • b fagan says

          5 Aug 2025 at 8:36 PM

          Hi Jonathan and MA,
          My question was regarding the potential solution to the Navier-Stokes equations – it being useful or beneficial in climate research or in the fluid models for atmosphere and oceans – not about the general application of new computing tools more generically, thanks!

          Reply
          • Jonathan David says

            7 Aug 2025 at 11:01 AM

            Hi b fagan, Sorry if my reply wasn’t clear but the research cited in your link is of a theoretical and technical nature that is most likely of minimal relevance to climate science applications, so likely no.

          • Paul Pukite (@whut) says

            9 Aug 2025 at 4:54 AM

            The only aspect of Navier-Stokes that would be of any interest to climate scientists is in their simplified form, alternatively known as the primitive equations, shallow-water-equations, or Laplace’s tidal equations. There are some interesting further simplifications possible, and right now I ‘m analyzing a set of at last count 78 mean sea-level height measurements each spanning at least 100 years at monthly intervals. I have cross-validated a strong majority of these by holding out intervals of 10 to 30 years and training on the rest. This isn’t the conventional daily tidal analysis but modeling the long-term dynamics of the ocean volume, It extends also to the major climate indices such as ENSO, AMO, etc

            http://imageshack.com/a/mLK17/1
            In the link above, Brest is an example of a sea-level station.

            There should be interest in this.

  12. David says

    4 Aug 2025 at 10:01 AM

    Tomáš Kalisz,

    I pass on supporting your proposition. Given everything that’s going on in this country, I cannot support asking for commitment of precious time by scientists who already had full plates even before last week’s endangerment finding repeal announcement. And I don’t think Dr. Gavin Schmidt is who I would be presenting your idea to. I had time this weekend to go back and reacquaint myself with the issue, and now I’m confident in saying your questions, or theory needs to be approached differently then how you have chosen to go.

    Good luck to you. If this really matters to you then please go forward and make different choices then how you have thus far.

    Reply
    • Tomáš Kalisz says

      4 Aug 2025 at 11:37 AM

      In Re to David, 4 Aug 2025 at 10:01 AM,

      https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-836938

      Hallo David,

      Thank you very much for your response!

      Although this topic is not my highest priority, I am not going to abandon it. If you perhaps have a specific idea how I can (or should) change my approach, please do not shy to share.

      Greetings
      Tomáš

      Reply
      • Thomas says

        4 Aug 2025 at 8:12 PM

        Reply to Tomáš Kalisz

        Assuming you refer to the consequences of an AI-assisted solution to Navier-Stokes (rather than the prospect of AI running riot through science generally and climate models in particular): assuming this, there are perhaps two questions you raise.

        (1) Would the use of an approximation of Navier–Stokes in climate modelling benefit from more exact treatment?
        To be clear, GCMs do employ Navier-Stokes although at what level (& thus any benefit from a more exact treatment) of the simulation process is a bit beyond my paygrade.

        (2) Is the rough probability of these ‘singularities’, these “tsunami in a calm sea”-type events that Navier-Stokes apparently predicts (but which are absent from the approximations) probable-enough to be of climatological concern?
        I note the article you link-to appears to answer the second of these questions in the affirmative, telling us “these equations are essential for predicting phenomena as relevant as the weather, catastrophic floods, the movement of an airplane, or blood flow in a human being.” [my bold] Yet I do wonder if this statement has derived its list of “essential” uses from the longer list of optional and “helpful” uses of Navier Stokes presented by Wikkipedia.

        Greetings

        Reply
        • Tomáš Kalisz says

          5 Aug 2025 at 3:27 PM

          in Re to Thomas, 4 Aug 2025 at 8:12 PM,

          https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-836989

          Hallo Thomas,

          David replied to my question if he would be willing to join / support my plea to Dr. Schmidt:

          —
          27 Jul 2025 at 7:48 PM
          https://www.realclimate.org/index.php/archives/2025/07/unforced-variations-july-2025/comment-page-2/#comment-836497

          in re to gavin, 26 Jul 2025 at 6:38 PM,
          https://www.realclimate.org/index.php/archives/2025/07/unforced-variations-july-2025/comment-page-2/#comment-836426

          Dear Dr. Schmidt,
          I hope that the possibility that water availability for evaporation from land may influence climate sensitivity also raises curiosity of climate scientists.
          Therefore, I would like to repeat my question if the approach used by Lague et al.
          https://iopscience.iop.org/article/10.1088/1748-9326/acdbe1
          could be applicable also for a study directed to this yet unresolved problem.
          Thank you in advance for a comment and best regards
          Tomáš
          —

          As I am not a physicist nor a mathematician, I must apologize that I am not able to answer your questions regarding the AI-assisted solution to Navier-Stokes equations.

          Greetings
          Tomáš

          Reply
  13. Susan Anderson says

    4 Aug 2025 at 12:10 PM

    Horrors pile up: https://bsky.app/profile/npr.org/post/3lvl3ndslrm2n
    Why a NASA satellite that scientists and farmers rely on may be destroyed on purpose – https://www.npr.org/2025/08/04/nx-s1-5453731/nasa-carbon-dioxide-satellite-mission-threatened

    “The data the two missions collect is widely used, including by scientists, oil and gas companies and farmers who need detailed information about carbon dioxide and crop health.
    ….
    “The equipment in space is state of the art and is expected to function for many more years, according to scientists who worked on the missions. An official review by NASA in 2023 found that “the data are of exceptionally high quality” and recommended continuing the mission for at least three years.
    ….
    “The data from these missions is even more valuable than intended: The missions are called Orbiting Carbon Observatories because they were originally designed to measure carbon dioxide in the atmosphere. But soon after they launched, scientists realized that they were also accidentally measuring plant growth on Earth.
    ….
    “The carbon dioxide data that the instruments were originally designed to collect has revolutionized scientists’ understanding of how quickly carbon dioxide is collecting in the atmosphere. …. Satellite data … covers the entire Earth.
    ….
    “maintaining both OCO missions in orbit costs about $15 million per year, Crisp says. That money covers the cost of downloading the data, maintaining a network of calibration sensors on the ground and making sure the stand-alone satellite isn’t hit by space debris, … “Just from an economic standpoint, it makes no economic sense to terminate NASA missions that are returning incredibly valuable data,””

    [so, $200 million for a ballroom or 13 years of maintaining vital data]

    Reply
  14. Victor says

    5 Aug 2025 at 9:33 AM

    John Pollack says:

    Victor,

    We can always count on you to propose the no-brainer solutions.

    Has it occurred to you that your “solution” would require producing rising levels of industrial aerosols to counteract steadily rising CO2 levels, yet that production would keep pushing up CO2 further?

    V: Sorry but I fail to see the problem. According to mainstream accounts, the industrial aerosols produced during the period 1940-1979 were sufficient to totally counteract any warming produced by significantly rising CO2 levels. According to the same sources, it was only after anti-pollution methods were adopted that global temperatures began to soar after 1979, I don’t buy this for a minute, but it represents the mainstream view — without which there would be no evidence of a connection between CO2 and temperature.

    If that is indeed the case, then industrial aerosols produced by the burning of fossil fuels would be. in themselves, sufficient to counteract any warming effect. Thus no need to “push up” CO2 production.

    Reply
    • Ray Ladbury says

      5 Aug 2025 at 2:30 PM

      We got it! Weaktor, look no further for your epitath:

      “Sorry but I fail to see the problem.”

      Reply
    • nigelj says

      5 Aug 2025 at 5:42 PM

      Victor, your plan just isn’t a great idea as follows. The total global quantity of coal burning aerosols required to fully suppress warming now and into the future would be considerably greater than mid last century, because the total atmospheric concentration of CO2 is considerably higher now than mid last century. Burning coal will probably not produce enough aerosols, to suppress the warming fully, even with all sulphate aerosol filtering removed. It will certainly reach a point where CO2 concentrations get so high that burning the coal won’t produce enough aerosols to suppress the warming. Then we have a massive problem. I think that is JPs point.

      And the greater the quantity of aerosols required means the level of toxic air pollution would be considerably greater than mid last century.

      Reply
    • Kevin McKinney says

      5 Aug 2025 at 5:46 PM

      Another canard from Victor:

      According to mainstream accounts, the industrial aerosols produced during the period 1940-1979 were sufficient to totally counteract any warming produced by significantly rising CO2 levels.

      Nice try at rehabilitating the falsehood that there was “no warming from 1940-’79” by implication. However, it’s still not true. Yes, you can cherry-pick that span and find that a linear trend shows a very slight decline. However, it’s not that there was no warming; it’s that there was a huge temperature spike beginning in ’35 or so, peaking in about ’42, then declining as quickly (but not as far) to roughly ’51.

      Run a linear fit for ’35-’79 and you find a warming trend; do it instead for ’45-’79 and once again you get a warming trend. The real anomaly requiring explanation isn’t during ’40-’79; it’s during that ‘hump’ in the record, from ’35-’51.

      https://www.woodfortrees.org/plot/gistemp/from:1920/to:1989/mean:13/plot/gistemp/from:1940/to:1979/trend/plot/gistemp/from:1945/to:1979/trend/plot/gistemp/from:1935/to:1979/trend

      Did aerosols partially counteract warming during the span 1940-’79? Yes, and yes that is a “mainstream” view. But not entirely, for the simple reason that from ’45 onward you see warming.

      Reply
    • John Pollack says

      5 Aug 2025 at 7:54 PM

      V: Sorry but I fail to see the problem.
      J: Okay, it doesn’t occur to you, even after being pointed out. I don’t suppose this explanation will help, but I’ll do it anyway.

      In our highly oversimplified climate model, only two variables act to change GMST – CO2 levels and combustion aerosols (mostly from acid gases). From 1940 to 1979, GMST was approximately constant, while CO2 levels rose by about 25 ppm, from 310 to 335 ppm. The warming effect of the CO2 was countered by rising emissions of combustion aerosols of amount A. CO2 levels have now risen to about 425 ppm. So if we wanted to return temperatures to 1940-79 levels, we would need to emit A times (425ppm-310ppm)/25ppm = 4.6 A. In other words, since there is now so much more CO2 in the atmosphere than when we started, we would have to emit acid gases at 460% of the rate we were doing it before emissions controls were initiated in the 1970s. However, that would require more fossil fuel burning, which would result in more CO2 to be offset by still higher emissions.

      Whatever temperature level we wanted to maintain by increased emissions, we would have to keep emitting faster and faster to stabilize that temperature (or go to dirtier and dirtier emissions). That’s the problem with the solution you were proposing, albeit somewhat in jest.

      Reply
    • MA Rodger says

      6 Aug 2025 at 1:29 AM

      Occasionally when googling stuff, I have had a quick look at the “AI Overview” presented. I’ve been far from impressed with many such ‘offerings’ simply stating the obvious or making a right Horlicks of the attempt. My thoughts were that these “AI Overview” were generally pretty useless.

      Until now.

      Victor the Troll very often tosses the ball down some rabbit hole (as he does in this comment above) and rather than jumping in after it, this google “AI Overview” can do the job, retrieving the ball effortlessly.

      Thus Victor trolls in this comment that:-

      According to mainstream accounts, the industrial aerosols produced during the period 1940-1979 were sufficient to totally counteract any warming produced by significantly rising CO2 levels.

      In the past I would have had to look into the “mainstream accounts” to demonstrate that they didn’t ‘accord’ such a position, or ask Victor and rely on him to do it himself. (Fat chance!)
      But now a google search asking the question:-

      Do mainstream accounts say the industrial aerosols produced during the period 1940-1979 were sufficient to totally counteract any warming produced by significantly rising CO2 levels?

      and press the return key..

      No, mainstream accounts do not suggest that industrial aerosols produced between 1940 and 1979 completely offset the warming caused by rising CO2 levels. While aerosols did have a cooling effect, masking some of the warming, they did not negate the overall warming trend.

      Of course it isn’t entirely that simple but here it does quickly and effortlessly beggar the lie presented by Victor’s trolling. “Mainstream accounts” do not say what he says they do.

      Reply
      • Ray Ladbury says

        6 Aug 2025 at 8:47 AM

        So, I wonder if the Turing test is transitive? Weaktor is dumber than an AI, which in itself doesn’t pass the level of human intelligence. Therefore…

        Reply
      • Ron R. says

        8 Aug 2025 at 10:43 AM

        MAcRodger,

        My thoughts were that these “AI Overview” were generally pretty useless.

        Yeah, good and bad with AI. Just read that one thing AI is good for, though, is summarizing long video discussions, as when you just don’t have the time to watch a looong (and boring?) talk.

        Reply
  15. Susan Anderson says

    5 Aug 2025 at 11:13 AM

    Moving this to top level. Actually, the London fog of 1951 was not an isolated event.
    London Fog: A Century of Pollution and Mortality, 1866-1965
    https://files.ehs.org.uk/wp-content/uploads/2020/11/29060836/HanlonFullPaper2018.pdf
    [fwiw, London, like some other cities, suffers from meteorological inversion. San Jose CA has trouble with these. https://ntrs.nasa.gov/citations/19770052217
    https://en.wikipedia.org/wiki/Inversion_(meteorology) [I’m only an interested amateur]

    Might be a cautionary tale, but those who should be listening are arguing/yelling la la la la la I can’t hear you.

    Reply
  16. Scott Nudds says

    5 Aug 2025 at 8:27 PM

    https://futurism.com/white-house-orders-nasa-destroy-important-satellite

    White House Orders NASA to Destroy Important Satellite

    The White House has instructed NASA employees to terminate two major, climate change-focused satellite missions.

    As NPR reports, Trump officials reached out to the space agency to draw up plans for terminating the two missions, called the Orbiting Carbon Observatories. They’ve been collecting widely-used data, providing both oil and gas companies and farmers with detailed information about the distribution of carbon dioxide and how it can affect crop health.

    Reply
    • Ray Ladbury says

      6 Aug 2025 at 8:51 AM

      Pure scientific vandalism.

      Reply
      • Susan Anderson says

        8 Aug 2025 at 7:51 AM

        True waste fraud and abuse.

        Reply
  17. MA Rodger says

    6 Aug 2025 at 6:16 AM

    The NOAA STAR & UAH TLT numbers are posted for July, both showing a drop in the global anomaly, the STAR global anomaly +0.42ºC, down from June’s +0.54ºC.
    Unlike surface temperature which has been declining strongly since the start of the year, since January TLT has been rather stuck with no decline since the last months of 2024, having previously been pretty flat running at full-‘bananas’ Sept 2023 to Sept 2024.

    Recent STAR TLT global anomalies (& ERA5 SAT global anomalies)
    Ave Set23-Oct24 . +0.77ºC … … …(+0.76ºC)
    Nov24 … … … … … +0.58ºC … … …(+0.73ºC)
    Dec24 … … … … … +0.61ºC … … …(+0.76ºC)
    Jan25 … … … … … +0.48ºC … … …(+0.79ºC)
    Feb25 … … … … … +0.53ºC … … …(+0.63ºC)
    Mar25 … … … … … +0.53ºC … … …(+0.65ºC)
    Apr25 … … … … … +0.58ºC … … …(+0.60ºC)
    May25 … … … … … +0.54ºC … … …(+0.53ºC)
    Jun25 … … … … … +0.54ºC … … …(+0.48ºC)
    Jul25 …. … … … … +0.42ºC … … …(+0.45ºC)

    This July TLT drop is due solely to the SH anomaly with the NH recording a tiny rise.
    Looking back at the NH & SH TLT anomalies, the sticky global TLT anomaly since the start of the year is actually due to the SH anomaly showing a rise through this period after dropping Aug23-Jan24, while the NH has generally been dropping since Nov24.

    Reply
  18. Victor says

    6 Aug 2025 at 8:44 AM

    nigelj:

    “Victor, your plan just isn’t a great idea as follows. The total global quantity of coal burning aerosols required to fully suppress warming now and into the future would be considerably greater than mid last century, because the total atmospheric concentration of CO2 is considerably higher now than mid last century. Burning coal will probably not produce enough aerosols, to suppress the warming fully, even with all sulphate aerosol filtering removed.”

    V: You have a point. I hadn’t thought of that. CO2 remains in the atmosphere for some time, so suppressing the warming produced by burning fossil fuels by accepting the aerosols generated by the same process won’t be enough to compensate for the CO2 already emitted from previous burning events. Nevertheless, according to the mainstream view, the aerosols in question should be sufficient to suppress most if not all the warming produced by CO2 generated by fossil fuel burning per se. While the result would not account for all the warming, it would certainly, according to the mainstream view, make a significant difference. So why not at least consider it?

    What are the alternatives? Here’s what James Hansen has to say on that score: https://www.youtube.com/watch?v=8Ag3UVSrlhE&t=3671s

    Reply
    • nigelj says

      6 Aug 2025 at 7:03 PM

      Victor @ 6 Aug 2025 at 8:44 AM

      V: You have a point. I hadn’t thought of that. CO2 remains in the atmosphere for some time, so suppressing the warming produced by burning fossil fuels by accepting the aerosols generated by the same process won’t be enough to compensate for the CO2 already emitted from previous burning events. Nevertheless, according to the mainstream view, the aerosols in question should be sufficient to suppress most if not all the warming produced by CO2 generated by fossil fuel burning per se. While the result would not account for all the warming, it would certainly, according to the mainstream view, make a significant difference. So why not at least consider it?

      N: I’m not sure the mainstream views says the aerosols in question should be sufficient to suppress most if not all the warming produced by CO2 generated by fossil fuel burning per se. You quote a James Hansen video as evidence of the mainstream view. Hansen doesn’t represent the mainstream view on aerosols. He believes they have a stronger effect than the mainstream view.

      If as I said we continued to burn fossil fuels, and removed all filtering of sulphate aerosols, I would rather think the aerosols in question would probably only suppress a very limited proportion of the current warming.  And even if they did suppress ‘most’ of the warming right now, because the atmospheric concentrations of CO2 would just continue to grow into the future the effect of the aerosols on warming will continually reduce. So what do we do then? Burn even dirtier coal? See the dilemma?

      I did once consider your idea. I did once consider that our attempts to remove sulphate aerosols have aggravated the warming trend, so why not just removing all filtering of sulphate aerosols? But you get into the difficulties I mention and levels of air pollution would obviously get quite serious. It just makes more sense to me to reduce emissions to net zero. Coal wont last forever so we need other options anyway.

      I suggest you also read the latest response posted by John Pollack @ 5 Aug 2025 at 7:54 PM. It shows the problems of your idea and quantifies the effects better than I can:

      “In our highly oversimplified climate model, only two variables act to change GMST – CO2 levels and combustion aerosols (mostly from acid gases). From 1940 to 1979, GMST was approximately constant, while CO2 levels rose by about 25 ppm, from 310 to 335 ppm. The warming effect of the CO2 was countered by rising emissions of combustion aerosols of amount A. CO2 levels have now risen to about 425 ppm. So if we wanted to return temperatures to 1940-79 levels, we would need to emit A times (425ppm-310ppm)/25ppm = 4.6 A. In other words, since there is now so much more CO2 in the atmosphere than when we started, we would have to emit acid gases at 460% of the rate we were doing it before emissions controls were initiated in the 1970s. However, that would require more fossil fuel burning, which would result in more CO2 to be offset by still higher emissions.Whatever temperature level we wanted to maintain by increased emissions, we would have to keep emitting faster and faster to stabilize that temperature (or go to dirtier and dirtier emissions). That’s the problem with the solution you were proposing, albeit somewhat in jest.”

      Reply
      • Kevin McKinney says

        9 Aug 2025 at 3:20 PM

        Of course, if we want to counteract warming via the albedo effects of (mostly) sulphate aerosols, there’s no need to burn fossil fuels to do it. For example, here is a relatively recent proposal:

        https://www.science.org/doi/10.1126/sciadv.abe3416

        Burning more fossil fuels isn’t the only way to manage albedo: just the absolute stupidest.

        Reply
    • Pedro Prieto says

      6 Aug 2025 at 8:52 PM

      Reply to Victor et al
      While the result would not account for all the warming, it would certainly, according to the mainstream view, make a significant difference. So why not at least consider it?
      What are the alternatives? Here’s what James Hansen has to say on that score:
      https://www.youtube.com/watch?v=8Ag3UVSrlhE&t=3671s

      But more important is what Hansen said after the section you point to:
      “”One gallon (3.7 litres) of gasoline or petrol is the equivalent of several hundred hours of work by a healthy adult. That’s extremely valuable. And unless you have an equally good alternative, and equally priced, people are going to keep using that — because there are other parts of the world — China, India, Africa — who want to raise their living standards. That makes it difficult… Solar may look cheap when the sun is shining, but you have to take account of the whole energy system. You need reliable energy, 24/7.””

      And more than just reliability — we need the right kind of energy for the work needing to be done.

      It was never just about emissions. It was always about energy.

      Real wealth — the kind that sustains civilization — isn’t created by money, policy, or innovation alone. It’s created by applying high-quality energy to transform the natural world and do work. That’s what built the industrial era — and it was only possible because we stumbled on a vast, cheap, one-time inheritance of concentrated solar energy in fossil fuels.

      Industrialization began with water-powered mills. Then came coal: a single ton delivering the equivalent of a year’s work by a horse or five years of human labour. Later, oil: one barrel equals 4.5 years of human labour. That’s why we built steel, concrete, plastics, global logistics, and fed billions — because the energy came first. Not the tech. Not the markets. The energy.

      Renewables are useful — but they are not equivalent in Energy. Electricity can run lights and appliances, and even power passenger transport. But it can’t produce the extreme heat or act as feedstock for steel, cement, plastics, and fertilizer. It can’t run airliners, ships, missiles, mining equipment, or industrial machinery. These aren’t political choices — they are thermodynamic limits.

      We are now trying to sustain a civilization built on $5, $10, now $80 barrels of oil using energy systems that, if priced at the labour-equivalent for the work produced, would cost $250,000 per barrel. That’s not a transition — it’s collapse in disguise.

      Yet our institutions — economists, politicians, and even many scientists — still act as though clever accounting and better batteries can overcome entropy. The IEA claims we’re entering a “new age of electricity” providing only a fraction of our energy needs while ignoring both physical and economic reality. This isn’t “decarbonization” — it’s the disintegration of the systems we depend on for our survival, without anything truly capable of replacing them.

      Net Zero, as currently imagined, is a myth. Not because emissions don’t matter — they do — but because it assumes we can swap energy sources without consequence. We can’t. And pretending otherwise wastes time, destroys trust, and increases systemic vulnerability.

      This isn’t pessimism.
      It’s thermodynamics.

      Basic physical reality is being ignored — by scientists, economists, politicians, and activists alike. Ignored by the UN, by governments, and by the entire IPCC and climate modelling community. But denial cannot delay reality forever.

      Reply
      • nigelj says

        6 Aug 2025 at 10:42 PM

        PP said: “Renewables are useful — but they are not equivalent in Energy. Electricity can run lights and appliances, and even power passenger transport. But it can’t produce the extreme heat or act as feedstock for steel, cement, plastics, and fertilizer. It can’t run airliners, ships, missiles, mining equipment, or industrial machinery. These aren’t political choices — they are thermodynamic limits.”

        It’s possible to make many of those products with electricity generated by renewables and non fossil fuels feedstocks. For example steel can be made in electric arc furnaces without coal or very little coal. The Haber-Bosch process, which produces ammonia, (for fertilisers) can be modified to use renewable energy sources and potentially hydrogen produced from renewable electricity. Zero carbon fuels are being seriously considered for aircraft. It’s not at all clear why industrial machinery can’t be powered by electricity.

        If it’s not possible to make all those products and power ALL those applications with renewable electricity or zero carbon fuels, or do it economically, we will have to continue using some fossil fuels. for some things. We have still at least reduced the global warming problem, and become less dependent on fossil fuels. Remember also fossil fules are a very limited finite resource, so we have to find alternatives one way or the other.

        We could still end up in a collapse scenario whatever option we choose whether its renewables, business as usual burning of fossil fuels, or something else. Guess what. We will have to deal with it as best we can. Renewables look like our best option, that minimise the risk of collapse while minimising environmental harm overall.

        PP said: “We are now trying to sustain a civilization built on $5, $10, now $80 barrels of oil using energy systems that, if priced at the labour-equivalent for the work produced, would cost $250,000 per barrel. That’s not a transition — it’s collapse in disguise.”

        Please provide proof of those numbers. Please state the exact source and page reference and copy and paste the calculations.

        Reply
      • Barton Paul Levenson says

        7 Aug 2025 at 8:24 AM

        PPr: Electricity can run lights and appliances, and even power passenger transport. But it can’t produce the extreme heat or act as feedstock for steel, cement, plastics, and fertilizer. It can’t run airliners, ships, missiles, mining equipment, or industrial machinery.

        BPL: Have you heard about electric arc furnaces? They had one at the US Steel Edgar Thomson works when I worked there 1988-1992. Electric planes are already being flight-tested. Ships with sails are coming back, though the modern sails look very different from the massively rope-rigged designs of previous centuries. Industrial machinery can run off biofuels or green hydrogen. Sweden is building a hydrogen-fueled steel plant right now.

        Reply
        • Pedro Prieto says

          7 Aug 2025 at 11:50 PM

          BPL: Have you heard about electric arc furnaces? They had one at the US Steel Edgar Thomson works when I worked there 1988-1992. Electric planes are already being flight-tested. Ships with sails are coming back, though the modern sails look very different from the massively rope-rigged designs of previous centuries. Industrial machinery can run off biofuels or green hydrogen. Sweden is building a hydrogen-fueled steel plant right now.

          Pedro: You should buy up as many shares in those companies as you can Barton. You’ll make a huge profit. Or your descendants will. /s We also know why EAF is a such a “winner” for the US.

          China’s heavy reliance on blast furnaces is largely because BF steel production delivers the high-quality steel required for critical, high-performance applications such as shipbuilding, submarines, bridges, and infrastructure. The established BF capacity and availability of iron ore feedstock support this large-scale production, which remains essential despite growing interest in greener, scrap-based EAF technologies.

          Horses for courses. Donkeys for other uses.

          Nigel: Please provide proof of those numbers. Please state the exact source and page reference and copy and paste the calculations.

          Pedro: No, I won’t. Try Gemini or better yet read a book or two.

          Reply
          • Barton Paul Levenson says

            8 Aug 2025 at 8:20 AM

            Nigel: Please provide proof of those numbers. Please state the exact source and page reference and copy and paste the calculations.

            Pedro: No, I won’t. Try Gemini or better yet read a book or two.

            BPL: The burden of proof is on the affirmative. That which can be asserted without evidence can be dismissed without evidence.

          • Pedro Prieto says

            9 Aug 2025 at 2:40 AM

            Suddenly EAFs using recycled scrap versus blast furnaces and critical applications no longer matters. OK. The affirmative evidence Nigel and Barton seeks is easily found under my ‘name’ for it is well known and easily located. The lack of knowledge here is not my responsibility to fix.

  19. Victor says

    6 Aug 2025 at 9:10 AM

    According to Mr. Rodger:

    In the past I would have had to look into the “mainstream accounts” to demonstrate that they didn’t ‘accord’ such a position, or ask Victor and rely on him to do it himself. (Fat chance!)
    But now a google search asking the question:-

    Do mainstream accounts say the industrial aerosols produced during the period 1940-1979 were sufficient to totally counteract any warming produced by significantly rising CO2 levels?

    and press the return key..

    No, mainstream accounts do not suggest that industrial aerosols produced between 1940 and 1979 completely offset the warming caused by rising CO2 levels. While aerosols did have a cooling effect, masking some of the warming, they did not negate the overall warming trend.

    V: By accessing Google you are, in effect, accessing the AI engine, which is notoriously unreliable. In fact, there was no overall warming trend during this period: https://www.woodfortrees.org/plot/gistemp/from:1920/to:1989/mean:13/plot/gistemp/from:1940/to:1979/trend

    Reply
    • Ray Ladbury says

      6 Aug 2025 at 3:02 PM

      Funny thing about Weaktor’s graph. Change the beginning or end point by just 5 years, and you are back to a positive trend. Why it’s almost as of Weaktor dishonestly cherrypicked his beginning and endpoints to achieve his desired result.

      Gee, and 1940 was just an ordinary year, wasn’t it? Nothing of note going on at all, was there?

      Reply
      • Victor says

        6 Aug 2025 at 10:35 PM

        Changing the beginning and endpoints by 5 years would be cherry picking. I chose 1940 and 1979 as endpoints because they represent clear turning points in the temperature record. That’s NOT cherry picking. This “mid-century hiatus” is widely recognized among climate scientists. In any case, there is no sign of any warming trend.

        Reply
        • Ray Ladbury says

          8 Aug 2025 at 7:34 AM

          You chose them because they give you the answer you wanted. THAT is the very definition of cherrypicking.

          Reply
          • Thessalonia says

            8 Aug 2025 at 10:09 PM

            Is that what James Hansen does too? He uses 1910 to 1940 and 1940 to 1970. Is he cherry picking?

            Victor is correct when he states- This “mid-century hiatus” is widely recognized among climate scientists. It’s recorded in the climate data sets too.

          • Jonathan David says

            12 Aug 2025 at 9:17 PM

            And does Dr Hansen also reach the same conclusion as does Victor? Namely, that there is no correlation between global warming and atmospheric CO2?

      • MA Rodger says

        7 Aug 2025 at 11:38 AM

        Ray Ladbury,
        Victor the Troll seems to be missing the point I made up-thread.
        He said his grand assertion was repeating the findings of “mainstream accounts.” My assertion (backed-up by Google’s unreliable AI bot) was that he was taking bullshit because there is no “mainstream account” presenting such findings.
        I thought Victor would hold his position. AI bots are not big-brained all-knowing sources that are never wrong. But in this case, if me & the AI bot both are considered wrong, it is up to Victor to demonstrateour error and provide his “mainstream”references backing-up his grand assertion.

        But Victor ignores this flaw in his grand assertion and replies blindly repeating part of a presentation from up-thread which was given to show that the point-of-interest was not whether an OLS through GISTEMP-or-whatever 1940-79 yielded a negative trend, or even a positive trend. (The trend is actually indeterminate using GISTEMP being -0.10ºC/decade ±0.41ºC 2sd.) Rather the true point-of-interest was argued up-thread by Kevin McKinney and now also by you to be the global temperature spike of the mid-1940s and what caused it.

        In similar vein, I thought also to employ a WoodForTrees plot of GISTEMP. As well as Victor’s precious 1940-79 regression, it provides a 1920-40 regression and a 1979-99 regression.
        But goodness me! These three OLS trends don’t seem to fit together at all well!!! The fit is actually complete pants!!!!! What is going on? Perhaps Victor can explain. Or perhaps not.
        But if he does, while he’s at it (this the actual reason for my visit to WoodForTrees), perhaps Victor can explain why “mainstream accounts.” show the increasing climate forcing back in 1920-40 was less than a third of the forcing 1979-99 explain when the rates of warming shown by the regressions for those two periods is so similar? Could it be that the point-of-interest here really is the global temperature spike of the mid-1940s and identifying whatever caused it?

        I would ask Victor if he were capable of answering questions. Maybe asking an AI bot would be more useful.

        Reply
        • Victor says

          7 Aug 2025 at 11:41 PM

          I’m not sure what to make of your incoherent nitpic, Mr. R. It’s clear, however, that you’ve missed the point. The “mainstream view” to which I was referring is the notion that the lack of any warming trend during the 40 year mid-century period was due to the cooling effect of industrial aerosols. I’m assuming that this is your view as well. So what, my friend, is your problem?

          Reply
          • MA Rodger says

            8 Aug 2025 at 12:21 PM

            Victor the Troll,
            Your response doesn’t pass muster, not by a long chalk. More correctly, none of you responses do. That is the problem.

            You were quite specific in your comment up-thread. You were not invoking some nebulous “notion.” You positively cited “mainstream accounts“ to defend your silly position, saying“the industrial aerosols produced during the period 1940-1979 were sufficient to totally counteract any warming produced by significantly rising CO2 levels.” If you mis-spoke and you were citing some “notion” that only exists inside your head, fine. Man-up and admit it, But if not and you believe it does exist outside your head (you calling it “mainstream” suggests this is the case), then where is it? Where is the evidence of its existence?

            It shouldn’t be a difficult question to answer, Victor, given the answer is simply requiring you to identity of some is supposedly “mainstream account” you’ve been telling us about.

            But maybe you are needing some assistance. Perhaps a link to the relevant part of the most-recent UN IPCC AR might help. The ARs are usually considered “mainstream” for things AGW. So try AR6 Chapter 3 Section 3.3.1.1.2 ‘Human Influence on the Atmosphere and Surface: Temperature: Surface Temperature: Detection and attribution

          • Thessalonia says

            8 Aug 2025 at 9:01 PM

            Reply to Victor – So what, my friend, is your problem?

            A waste of time asking or even thinking about that question. It is very weak to be harassing or ridiculing a member of the public over the choice of one word to express their generally correct representation of what the mainstream climate science reports about warming history.

            The rise in CO₂ emissions during that time period was significant, at historical record levels, so the small net warming is consistent with strong offsetting by aerosols. The core dispute is that Victor’s OP slightly exaggerated use the word “totally”. But the rebuttal overreached even more by totally denying what the data plainly shows from all “mainstream accounts, including the IPCC AR6 Chapter 3 Section 3.3.1.1.2”

            From the IPCC observational dataset (global surface temperature anomalies, 1850–2024), here’s what the data show for your periods of interest:

            1940 → 1970: –0.003 °C/decade (slightly cooling overall; total change ≈ –0.01 °C)

            1950 → 2000: +0.019 °C/decade (≈ +0.95 °C total warming)

            1970 → 2000: +0.070 °C/decade (≈ +0.21 °C total warming)

            So yes — the observed 1940–1970 trend is essentially flat or slightly cooling, despite rising CO₂ emissions. This does point to substantial offsetting effects (aerosols, internal variability, volcanic activity) during that mid-century period.

            If you include 1940–1979 instead of stopping at 1970, the warming rate is still small but positive — suggesting the rebound after the mid-century cooling didn’t really kick in until the late 1970s.

            Here’s the trend specifically for 1940 to 1979 from the IPCC-style dataset:

            1940 → 1979: warming trend of about +0.019 °C per decade,

            Total warming over those 40 years: approximately +0.07 °C.

            So in that mid-century 40-year span, the global temperature was essentially flat with a very slight warming — well below the robust warming seen after 1980.

            That means any CO₂ warming during that period was mostly masked or offset by cooling effects like aerosols and internal variability, but the total net warming still wasn’t zero; it was just very small.

            In Summary:
            Victors use of the word “totally” was inappropriate but everything else he stated was an accurate presentation of the “mainstream view” and the “mainstream accounts“.

            I can fetch and compute precise values (e.g. Berkeley Earth, HadCRUT5, GISTEMP, NOAA, ERA5) for 1940→1970 and 1940→1979 and give a little table showing each dataset’s delta and the reference baseline they use, but what be the point when the broad global historical record is already clear?

        • Thessalonia says

          8 Aug 2025 at 9:10 PM

          Now, hear this and try to remember it forever:

          The global push to reduce sulfur dioxide (SO₂) emissions from coal-fired power plants—primarily to combat acid rain—happened mainly in the 1970s and 1980s, with implementation timelines varying by region:

          United States:
          The U.S. started regulating SO₂ emissions in the early 1970s with the Clean Air Act of 1970, but major sulfur reductions came later with the 1980 Acid Rain Program amendments and especially the 1990 Clean Air Act Amendments. The latter introduced a cap-and-trade system that greatly cut SO₂ emissions starting in the mid-1990s.

          Europe:
          Western European countries began sulfur emission controls in the 1970s and 1980s, accelerated by agreements like the 1979 Geneva Convention on Long-Range Transboundary Air Pollution (LRTAP). The 1985 Helsinki Protocol and later the 1994 Oslo Protocol set binding sulfur emission reduction targets through the 1990s.

          Other regions:
          Implementation in developing countries occurred later, mostly in the 1990s and 2000s, often following technological upgrades or fuel-switching.

          Summary:
          While some sulfur emission regulations began in the 1970s, significant, large-scale sulfur scrubbing and emissions reductions from coal plants were widely implemented during the 1980s and ramped up in the 1990s, especially in the U.S. and Europe.

          This timeline is important when considering aerosol forcing impacts on mid-to-late 20th-century climate trends because:

          Aerosol emissions (and cooling) peaked mid-century when industrial SO₂ emissions were high.

          Cleaner technologies and regulations gradually reduced aerosols from the 1980s onward, reducing aerosol cooling and contributing to observed warming acceleration after ~1980.

          Denial is not a river in Egypt. The logical fallacies and sophistry is not helping anyone.

          Reply
  20. David says

    6 Aug 2025 at 4:59 PM

    Out today on James Hansen’s site:
    .
    “Seeing the Forest for the Trees”
    James Hansen, Pushker Kharecha
    .
    “Abstract. Climate sensitivity is substantially higher than IPCC’s best estimate (3°C for doubled CO2), a conclusion we reach with greater than 99 percent confidence. We also show that global climate forcing by aerosols became stronger (increasingly negative) during 1970-2005, unlike IPCC’s best estimate of aerosol forcing. High confidence in these conclusions is based on a broad analysis approach. IPCC’s underestimates of climate sensitivity and aerosol cooling follow from their disproportionate emphasis on global climate modeling, an approach that will not yield timely, reliable, policy advice.”
    .
    http://www.columbia.edu/~jeh1/mailings/2025/ForestTrees.06August2025.pdf

    Reply
    • Thessalonia says

      7 Aug 2025 at 12:18 AM

      Enticing

      The case with climate sensitivity 3°C for doubled CO2 and IPCC aerosol
      forcing does not readily achieve the recent 1.6°C global temperature level nor produce a global
      temperature jump of 0.4°C in the past few years. These shortcomings led to consternation in the
      climate research community that “something is wrong;” Schmidt concluded that no
      combination of known mechanisms can explain observed global warming.

      We disagree. The problem that IPCC has gotten itself into results in part from their excessive
      dependence on GCMs. Independent information – from paleoclimate and modern climate
      observations – shows with greater than 99% confidence that climate sensitivity is substantially
      higher than IPCC’s best estimate. Once that is realized, it follows that IPCC also underestimated
      the strength of the aerosol forcing. With realistic climate sensitivity and aerosol forcing, there is
      no big mystery in recent global temperature change.

      It is unsurprising that, for decades, most GCMs yielded climate sensitivity near 3°C for doubled
      CO2, given the simple treatment of cloud physics in early GCMs, which, e.g., did not model
      cloud microphysics. GCM “beauty contests” that occur with the major IPCC reports tend to force
      a choice of cloud and aerosol models such that the GCMs yield realistic global warming in the
      past century. Once the choices of cloud modeling and aerosol forcing are set, this tends to make
      it difficult, or at least slow, to change either of them. Further development of the GCMs is then
      like changing the direction of a barge in a sea of molasses.

      4. Summary: seeing the forest for the trees

      Reply
      • Barton Paul Levenson says

        8 Aug 2025 at 8:25 AM

        Th: Independent information – from paleoclimate and modern climate
        observations – shows with greater than 99% confidence that climate sensitivity is substantially
        higher than IPCC’s best estimate.

        BPL: Look again.

        Hegerl Gabriele C., Crowley Thomas J., Hyde William T., Frame David J. 2006. “Climate Sensitivity Constrained by Temperature Reconstructions over the Past Seven Centuries.” Nature 440, 1029-1032 (letter).

        Hoffert, Martin I., Covey, Curt 1992. “Deriving Global Climate Sensitivity from Palaeoclimate Reconstructions.” Nature 360, 573-576.

        Reply
    • MA Rodger says

      7 Aug 2025 at 11:20 AM

      David,

      There are actually two versions of this Hansen et al ‘Seeing the Forest for the Trees’, the 14-page version you link-to and a shorter 4-page version which misses out Sec 1-3 and the appendix.

      It appears that ‘Seeing the Forest for the Trees’ is meant to “summarize the most important conclusions” of the 2023 ‘Pipeline’ paper and the 2025 ‘Are we well informed? paper. In doing so, it is perhaps providing a more scientific account by concentrating more on the points of contention, the sciency bits where Hansen et al are at odds with the IPCC. But at first sight it appears to fall short of explicitly providing a definitive account of the Hansen-IPCC contention. And despite the claims, there are still questions to be answered to achieve that ‘knock-out’ thesis that overturns the IPCC position.

      Consider Section 1 of ‘Forest for Trees’. The 2023 ‘Pipeline’ paper presented a thesis that concluded “that ECS for climate in the Holocene-LGM range is 1.2°C ± 0.3°C per W/m^2″(2sd) [= ECS=4.7°C ± 1.2°C for 2xCO2] and ‘Forest for Trees’ condenses this into its Section 1. The disagreement with IPCC is described as one of assessing the ΔT since the LGM. ‘Forest for Trees’ tells us IPCC using an obsolete ΔT=3.6°C while recent findings give ΔT=7.0°C. Yet IPCC AR6 sec 2.3.1.1.1 assesses these same recent findings and concludes from them ΔT=5°C–7°C. It appears that ΔT is not the point of contention. Thus Section1 of ‘Forest for Trees’ is punching at thin air rather than delivering a ‘knock-out’ thesis.

      Sections 2&3 are more meaty but the assertions presented do need nailing down.
      Section 2 seems to be no more than say that ECS(no feedback) =1.2°C and this is doubled by cloud feedback assumed from the CERES data and doubled again from WV & ice feedbacks, this delivering the ECS=4.8°C derived in Section 1.
      Section 3 is saying that the aerosol forcing 1970-2005 will allow ECS to be derived. If aerosols 1970-2005 is ‘flat’, ECS=3°C. If it increased +0.5Wm^-2, ECS=4.5°C. If it increased +1Wm^-2, ECS=6°C. But ‘Forest for Trees’ insists this 1970-2005 aerosol forcing must increase to allow the “bananas” of late 2023. It appears. ECS=3°C won’t hack it.
      I think this conclusion requires an assumption for the cause of the “bananas”.

      One minor point that spring-out is the “best linear fit” numbers in Fig2a. This is apparently GISTEMP data to June 2025 but the “best linear fit” 2010-to-date is given as +0.30°C/dec which seems very low. Using OLS through this GISTEMP data, I get +0.36°C/dec.

      Another point, in ‘Forest for Trees’ there is perhaps extra emphasis placed on the work of Tselioudis et al** which only got passing mention in ‘Are we well informed?. Given Tselioudis was a co-author, only giving a passing mention seems a bit miserly. The mention was that there is plenty of recent albedo forcing, enough to “also accommodate the cloud feedback implied in the shifting of climate zones identified by Tselioudis et al.(2024)”.)
      (** Their most-recent paper is Tselioudis et al (2025) ‘Contraction of the World’s Storm‐Cloud Zones the Primary Contributor to the 21st Century Increase in the Earth’s Sunlight Absorption’, not referenced by ‘Forest for Trees’.)

      Reply
  21. Thessalonia says

    6 Aug 2025 at 9:14 PM

    The End of Energy Illusions…will arrive eventually. Will it be too late? Probably.

    The crisis in the UK electricity market isn’t just about price distortion or poor policy design — it’s a symptom of a much deeper collapse: the end of surplus energy as the basis of modern prosperity.

    For over a century, we lived off the back of concentrated fossil energy that could deliver, as Nate Hagens puts it, the equivalent of 4.6 years of human labour in every barrel of oil. That energy dividend is what built everything we called “wealth” — not just our machines, transport, and food systems, but the entire social complexity of modern industrial life.

    That era is ending. Not because oil disappeared, but because our systems grew so overbuilt, so hungry, so brittle, that they cannot function on declining energy returns. And yet, instead of facing this reality, we’ve retreated into fantasies. The idea that wind and solar — diffuse, intermittent, and dependent on fossil supply chains — can seamlessly replace the energetic foundation of civilization is not just wrong. It’s dangerous. It tells people we can “transition” without sacrifice, restructure markets without rethinking physics, and preserve our lifestyles through financial reshuffling and moral virtue.

    The UK’s electricity “market” is a neoliberal hallucination, maintained through bureaucratic sleight of hand and cross-subsidies that mask the true costs of intermittency. What was once sold as a moral project (Net Zero) has now become an economic wrecking ball — destroying affordability, weakening resilience, and pushing public trust past the breaking point. And as the fossil inheritance fades, we’re left trying to run a surplus-energy civilization on deficit-energy systems.

    This was never about carbon alone. It was always about energy. And now the bill is coming due.

    There is a core thermodynamic truth that’s been ignored, misunderstood, or deliberately suppressed: modern civilization was built on a one-time inheritance of cheap, dense fossil fuel energy. Pretending we can maintain it with intermittent, diffuse renewables and financial engineering is pure delusion.

    And beneath the rhetoric of Net Zero lies a quiet panic: that we have no replacement, only peer-reviewed myths.

    Reply
  22. Thessalonia says

    6 Aug 2025 at 9:23 PM

    why is that so? what difference does it make?

    1. UK electricity prices are the highest in the world due to the combined effects of physical intermittency in renewables and a flawed neoliberal approach to energy policy. While physics dictates that solar and wind cannot provide consistent power, the UK has chosen to engineer an artificial “market” in electricity, despite the fact that electricity supply is a natural monopoly. Instead of operating a unified public system, the grid is split among various private actors—generators, operators, retailers—resulting in inefficiencies and misguided regulation. Net zero policies have added to the burden, with growing levies funding heat pump rollouts and the transition from gas.

    2. The core structural problem lies in how electricity prices are allocated, especially under a system dependent on intermittent renewables. Because solar and wind require constant backup from “firm” sources like gas or imported electricity, their real cost includes not only their infrastructure but also the cost of keeping backup sources on standby. UK nuclear provides a small but steady baseload, while pumped hydro is minimal and large-scale battery solutions remain distant. This leads to inflated margin costs, as backup sources are paid to wait for demand.

    3. Wind is prioritized over gas under current regulations, distorting the price mechanism. Wind gets dispatched first, forcing gas generators to idle while still incurring overheads. Yet all generators are paid at the highest marginal rate (typically gas), meaning wind companies benefit from high gas prices without the same operating costs. This system rewards unreliability and penalizes flexible generation. The abandonment of cheap Russian gas for expensive LNG further pushes up prices, and the UK’s growing reliance on European imports adds price volatility and risk.

    4. Critics argue that the UK’s energy crisis is the product of ideological commitment to neoliberal net zero, not rational economics. Reform UK has proposed re-nationalising the grid to simplify costs and improve domestic security of supply. This wouldn’t eliminate renewables’ intermittency but would make their true costs transparent. However, the current political class is unlikely to pursue such reforms. If nothing changes, a breaking point may arrive by 2029, when energy costs exceed what households and industry can bear.

    5. Public opinion is turning against net zero as its impacts become more severe and visible. While once a popular “luxury belief” supported by climate-aware citizens, net zero now carries real economic costs—especially after the UK abandoned cheap energy sources. Critics note the futility of Britain’s sacrifices, given its tiny share of global emissions and the surge in coal use by China and others. As the rest of the world prioritizes energy security and development, Britain risks becoming an outlier, sacrificing its economy in pursuit of a goal others are ignoring.

    Reply
    • b fagan says

      7 Aug 2025 at 12:03 AM

      UK electricity prices are behind Italy and Ireland, so there’s that. Interesting that you miss the “low-cost” stability of Russian gas. What’s the true price of fuel addiction when Putin tried to extort complacency from his customers when he invaded Ukraine?

      You also falsely claim “solar and wind require constant backup from “firm” sources like gas or imported electricity”. It is false because ALL sources of generation require constant backup. If DRAX or Pembroke or some other big thermal plant was going full blast and tripped offline, its output would need to be replaced instantly from all available reserve capacities or load-shedding would kick in to prevent blackouts. Thermal plants have maintenance windows (scheduled and unscheduled downtime for hours to months) and, again, the grid needs replacement resource for that. Firm power is increasingly from aggregated demand response, or from large battery installations (faster than spinning reserve) and also from better forecast of intermittent sources as well as (important) cross-border interconnections which are crucial for smaller geographies.

      If you need an illustration, look at Texas’ ERCOT in February 2022. They produce and use far more electricity than the entire UK and they were less than five minutes from total loss of grid mostly because of failures of ‘firm’ gas plants, as well as coal plants and one of their four nuclear plants – wind was only expected to be 16% of supply and it didn’t fail completely, just some turbines they chose not to winterize were offline a bit. Solar outproduced expectation. And yes, they self-inflicted that disaster (several hundred deaths) because of an overreliance on gas, and no real electricity import capacity from places north of them still generating power in the cold, because they insist on being the Lone Star State a bit too often for the good of their non-billionaire population. By the way, Texans have now been saving billions a year due to renewables and storage chopping down peaker gas plant prices, too.

      I fear you are seeing some true growing pains in the UK, but perhaps not looking at the higher costs of not pushing ahead.

      OBR: Net-zero is much cheaper than thought for UK – and unchecked global warming far more costly

      “Reaching net-zero will be much cheaper for the UK government than previously expected – and the economic damages of unmitigated climate change far more severe.
      These are two key conclusions from the latest report on risks to the government finances from the independent Office for Budget Responsibility (OBR), which includes a chapter on climate change.

      The new OBR report shows very clearly that the cost of cutting emissions to net-zero is significantly smaller than the economic damages of failing to act.

      https://www.carbonbrief.org/obr-net-zero-is-much-cheaper-than-thought-for-uk-and-unchecked-global-warming-far-more-costly/

      Michael Liebreich’s excellent Cleaning Up podcast just posted a piece talking about the state of things as politics leads to more attacks on net zero – about halfway through he discusses some of old Tony Blair’s musings about carbon capture and storage somehow becoming financially viable (hah), for example. Worth a listen.

      The Energy Transition Is Not Dead — The Pragmatic Climate Reset Part 1
      https://www.youtube.com/watch?v=OHKGor2_BzQ

      PS – a reminder on “stability” when discussing generation requiring a steady flow of flammable materials delivered to power plants. The world is heading into a less-stable condition which will worsen rather than improve the less we do about reining in climate change. Wars and breakdown of international stability do funny things to the ability to ship fuels long distances at sea or across multiple borders, some which may be war zones. Good thing that offshore platform skills from the oil industry transfer to offshore wind farms.

      Reply
      • Pedro Prieto says

        8 Aug 2025 at 12:29 AM

        b fagan says
        7 Aug 2025 at 12:03 AM
        Barton Paul Levenson says
        7 Aug 2025 at 8:27 AM
        Adam Lea says
        7 Aug 2025 at 5:01 PM

        It’s old, so I’m wondering it might be showing if redone today post-Covid post-Ukraine post-everything else.
        Exploring new possibilities for alleviating fuel poverty
        The number of households in fuel poverty in England has been increasing since 2004, following increases in fuel prices. The latest estimates put the number at 4.4 million (about 20% of households) in 2010 (Preston et al., 2010), up from 4 million in 2009 (or 18.4% of all households) according to the latest official figures (DECC, 2011).1 This contrasts starkly with the 1.7 million households, which were fuel poor in 2001 (ibid.).
        https://doi.org/10.1016/j.enpol.2011.11.059

        The UK is a first world nation.

        2018 cite https://www.sciencedirect.com/science/article/abs/pii/S0301421517308789
        It’s like circling the drain sometimes…. everything ends up at the same place

        Reply
    • Barton Paul Levenson says

      7 Aug 2025 at 8:27 AM

      Th: Wind is prioritized over gas under current regulations, distorting the price mechanism.

      BPL: Wind doesn’t generate CO2. Gas does. There are externalities associated with burning fossil fuels that are not reflected in the capital investment cost or the operations costs. Government intervention to counter externalities can work just fine. The price mechanism can’t handle externalities.

      Reply
    • Adam Lea says

      7 Aug 2025 at 5:01 PM

      https://bionic.co.uk/business-energy/guides/whats-going-on-with-energy-prices/

      “Why are energy prices so high?

      Supply and demand issues push up wholesale energy prices (that’s the amount your provider pays energy generators for the gas and electricity they supply to your business). And rising wholesale costs are often the biggest factor in rising energy prices. Here are some reasons why UK energy prices shot up and remain the highest in Europe.

      Lower renewable energy generation – Low winds, coupled with outages at some nuclear power stations, mean that a higher percentage of our electricity generation is using gas during its production. If you’re on a green energy deal that provides 100% renewable electricity, you’ll still see your rates increase. This is because the way the UK energy system works means that the price of renewable energy is tied to the price of gas – if gas prices go up, so do renewable energy prices.

      Low gas reserves – The UK has some of the lowest gas reserves in Europe, which means there’s almost no way of stockpiling gas to use it when needed. Capacity is equivalent to roughly 2% of the UK’s annual demand, compared with 25% for other European countries and as much as 37% in Europe’s four largest storage holders.

      Insufficient government support – Although the government’s £15 billion support package will see households credited with £400 over six months from October, this won’t have as big an impact as measures taken in other European countries. France, for instance, has capped electricity price increases to 4% until the end of the year.

      Issues with the energy market – 34 UK energy suppliers have gone bust since 2021. This is largely down to many of them having a business model that couldn’t cope with an increase in wholesale prices. And when suppliers go bust, consumers help to absorb the cost through higher bills. For instance, when Bulb ceased trading, it was such a big supplier – providing power to around 1.5 million homes and businesses – that the government placed it into ‘special administration’ instead of going through the ‘supplier of last resort’ process. Initial estimates suggested this process would cost £2.2 billion over two years, but figures from the Office for Budget Responsibility (OBR) show that an extra £4.6bn has been spent on handling the company, which will bring the total to £6.5 billion. This could add as much as £200 on to annual household energy bills.

      UK energy prices are also affected by global events.

      How do global events impact energy prices in the UK?

      The UK doesn’t operate in a bubble when it comes to energy. Global events — from political tensions to extreme weather — can quickly ripple through to your gas and electricity bills. Here’s how it happens.

      Global gas prices – The UK imports a lot of gas, especially liquefied natural gas (LNG) from the US, Qatar, and Norway. When global supply gets disrupted — by wars, sanctions, or bad weather — the price of gas soars.
      Because gas powers a big chunk of our electricity, higher gas prices often mean higher energy bills. For example, the Russia-Ukraine conflict cut Europe’s gas supply and sent UK prices soaring, even though Britain wasn’t a major buyer of Russian gas.

      Oil prices push up costs – Oil plays a smaller role in UK energy generation, but it still matters. When oil prices rise — for example, due to OPEC production cuts or tensions in the Middle East — transport and supply chain costs climb too. In some cases, gas prices are linked to oil, meaning costs can rise together.

      Extreme weather disruptions – Storms, droughts, and freezing winters can damage energy infrastructure or boost demand overnight. A cold snap across Europe – like the Beast from the East in 2018, for example – can drain gas supplies and force prices up across the UK.

      Supply Chain Setbacks – Pandemics, shipping delays, and global crises can hold up new energy projects, like offshore wind farms or gas terminals.

      When there’s less supply on the market, prices stay higher for longer.

      Currency Fluctuations – Energy is priced globally in US dollars. So if the pound (£) falls in value, it costs more to import gas and oil. Those higher costs can trickle down into your bills.

      Market Volatility and Speculation – Global traders react quickly to headlines, not just facts. Speculation about shortages or political risks can spike energy prices before anything even happens. This volatility filters through to the UK’s wholesale market, driving supplier costs higher.

      Life after lockdown – An increase in demand as lockdown restrictions eased across the globe. There’s more on that in the section below, titled: How did the pandemic affect energy prices?

      How did the pandemic affect energy prices?

      Let’s quickly go back to the first lockdown of early 2020, when a drop in demand saw energy prices drop to their lowest ever levels. Although wholesale prices had been dropping since hitting a high of £67.69 per Megawatt-hour (MWh) in September 2018, things bottomed out at just over £24 per MWh in April and May 2020, at the height of the first lockdown.

      Prices steadily increased late 2021, when we saw some massive spikes. An increase in demand was a big driver of the price hikes.

      A greater need for energy since the crash of spring 2020 saw gas prices increase more than fivefold and return to pre-pandemic levels.

      For the wholesale electricity market, there has been a reduction in available power supplies compared to last year. When combined with higher gas prices, this has led to an increase in the wholesale price of electricity.

      An increase in network and policy costs also pushed prices up.

      Higher electricity distribution and transmission costs have driven a rise in network costs, as has an increase in policy costs, such as the Renewable Obligation (RO). For reference, the RO is a levy placed on all licensed electricity suppliers to encourage them to source a proportion of the electricity they supply from renewable energy sources.

      The pandemic also saw more energy suppliers hit by ‘bad debt’ and many lost money because customers simply couldn’t afford to pay their energy bills. ”

      To be honest just about everything in the UK is expensive including food, transport, housing and utilities. Brexit has contributed to making some things even more expensive thanks to the extra costs businesses have to pay due to increased trade friction:

      https://www.youtube.com/watch?v=6TD5Vr3xnuw

      Populism nearly always harms those it claims to represent.

      Reply
    • patrick o twentyseven says

      7 Aug 2025 at 5:24 PM

      “commitment to neoliberal net zero,” Those arch-conservative hippies!

      Reply
    • b fagan says

      9 Aug 2025 at 6:45 PM

      A recent review of the spike in UK energy prices and the causes of same (hint – not renewables, not green levies)

      Factcheck: Why expensive gas – not net-zero – is keeping UK electricity prices so high

      https://www.carbonbrief.org/factcheck-why-expensive-gas-not-net-zero-is-keeping-uk-electricity-prices-so-high/

      And Dave Borlace’s excellent Just Have A Think reviews that report and explains the problem with basing your electricity prices on what tends to be natural gas, due to how power markets there set wholesale electricity prices.

      Why is UK Energy SO expensive?
      https://www.youtube.com/watch?v=xIpHxIbyD-M

      Reply
  23. Victor says

    6 Aug 2025 at 11:23 PM

    nigelj:

    If as I said we continued to burn fossil fuels, and removed all filtering of sulphate aerosols, I would rather think the aerosols in question would probably only suppress a very limited proportion of the current warming.

    V: Consider the following graph:
    https://i0.wp.com/everythingclimate.com/wp-content/uploads/2021/05/GISS-official-graph.png?w=904&ssl=1

    According to what I’ve chosen to call “the mainstream view,” the warming we see leading up to 1940 should have continued to rise from then on — assuming that rising CO2 levels produce rising temperatures. Instead we see an abrupt dip followed by a leveling until ca. 1979, a period of 40 years. If, as I feel sure you believe (I don’t), the lack of warming was due to the cooling effect of industrial aerosols, then the effects of those aerosols would have been powerful indeed. Powerful enough to totally suppress any warming produced by CO2 over 40 years. That’s what I’d call significant.

    If they were actually capable of completely neutralizing any warming that might have been produced by CO2 during this period, then I see no reason why aerosols produced by the same procedures wouldn’t similarly neutralize the warming effects of CO2 at any later time.

    N: And even if they did suppress ‘most’ of the warming right now, because the atmospheric concentrations of CO2 would just continue to grow into the future the effect of the aerosols on warming will continually reduce. So what do we do then? Burn even dirtier coal? See the dilemma?

    V: Yes. However, as should be clear from my response above, the effect of aerosols produced by fossil fuel burning would have to be (according to the mainstream view) extremely powerful. Thus opening the door once again to the full effect of such aerosols would have to make a significant difference. No need to burn “even dirtier coal.” The coal and other fossil fuels we now burn should be enough to bring temperatures down significantly.

    This need not be a permanent “solution.” Sooner or later, as it seems to me, we’ll be forced to turn to nuclear power. Until then, anything we can try to lessen the danger posed by “climate change” should (according to the mainstream view, not mine) be worth considering.

    Reply
    • nigelj says

      7 Aug 2025 at 5:38 PM

      Victor, with all due respect you still don’t understand what JP or myself are saying. In the middle of last century atmospheric concentrations of CO2 were at about roughly 320ppm with a certain moderate warming potential and aerosols negated that warming ( as you mentioned ). Now the atmospheric concentrations of CO2 are at about 420ppm which is higher and thus has a MUCH GREATER warming potential than mid last century. That means we now need considerably more aerosols “per unit of coal burned” to counter the warming. Just removing the filtering applied to coal fired stations won’t be enough. Look at the maths JP did. So the quantity of aerosols needed per unit of coal burned would be considerably more than mid last century, and would create considerable levels of pollution. And if we removed the aerosols, temperatures would instantly climb several degrees so we are stuck with it for a long time. This is not a good solution.

      Reply
    • Geoff Miell says

      7 Aug 2025 at 8:04 PM

      Victor: – “Sooner or later, as it seems to me, we’ll be forced to turn to nuclear power.“\

      Nuclear technologies are DEMONSTRABLY TOO SLOW to deploy from scratch to save humanity from planetary insolvency! Eleven countries completed 67 reactors over the decade 2014–2023—of which 37 in China alone—with an average construction time of 9.9 years. Add typically another 5 years for planning, approvals, financing, design, procurements and site preparations, and civil nuclear power projects are thus consistently requiring on average 1½ decades to deploy from scratch.

      See my Submission (#066), #066 Attachment 1, Supplementary Submissions (#066.1 – 066.3) & public hearing testimony on 11 Dec 2024, to the Australian Parliament House of Representatives Select Committee on Nuclear Energy re their Inquiry into nuclear power generation in Australia.
      https://www.aph.gov.au/Parliamentary_Business/Committees/House/Former_Committees/Select_Committee_on_Nuclear_Energy/Nuclearpower/Submissions
      https://www.aph.gov.au/Parliamentary_Business/Committees/House/Former_Committees/Select_Committee_on_Nuclear_Energy/Nuclearpower/Public_Hearings

      The inconvenient truths are:

      * For all intents and purposes, the global mean surface temperature (GMST) anomaly of +1.5 °C (relative to the 1850-1900 baseline) is here and now.
      * +1.5 °C anomaly is not a safe limit.
      * The world is currently warming at a rate of >0.1 °C per 3 years.
      * Daily atmospheric CO₂ concentrations are now exceeding 430 ppm (NOAA Mauna Loa Observatory).
      * Planet Earth’s albedo is at a record low.
      * Global mean sea level rise is approaching 6 mm/year (year-2024 was 5.9 mm/year per satellite altimetry).
      * The rate of sea level rise is demonstrably accelerating in an exponential-like manner.
      https://www.lithgowenvironment.au/docs/road-to-climate-ruin-geoff-miell-4jun25.pdf
      https://www.climatecodered.org/2025/07/the-15-degrees-climate-advocacy.html
      http://www.columbia.edu/~jeh1/mailings/2025/ForestTrees.06August2025.pdf

      Reply
  24. Sally says

    7 Aug 2025 at 2:44 AM

    Innovating our way to a cleaner greener future.

    https://x.com/marionawfal/status/1947247683040592158

    Chinese know-how, with American PR

    How could anyone not like this?

    Reply
  25. Barry E Finch says

    7 Aug 2025 at 10:52 PM

    “three sources of information: (1) paleo climate data”. 26 of the 37 paleo-climate proxy analyses in the PALEOSENS project have CO2*2 climate sensitivity at 3.6 (2.4 to 4.8) degrees.

    Reply
  26. Victor says

    8 Aug 2025 at 12:15 AM

    nigelj: Victor, with all due respect you still don’t understand what JP or myself are saying. In the middle of last century atmospheric concentrations of CO2 were at about roughly 320ppm with a certain moderate warming potential and aerosols negated that warming ( as you mentioned ). Now the atmospheric concentrations of CO2 are at about 420ppm which is higher and thus has a MUCH GREATER warming potential than mid last century. That means we now need considerably more aerosols “per unit of coal burned” to counter the warming.

    V: Look, nigel. For years now we’ve been told over and over again, that if we “turned off the fossil fuel spigot” global temperatures would eventually return to normal. However, as even James Hansen himself has asserted, eliminating fossil fuels would lead to worldwide disaster: https://www.youtube.com/watch?v=8Ag3UVSrlhE&t=3671s

    Now, according to the “mainstream view,” which I’m sure you share, the industrial aerosols produced during the mid-century period when we see NO sign of a warming trend, were sufficient to counteract any warming allegedly produced by significantly rising CO2 levels.

    In other words, according to the mainstream view, the cooling effect of aerosols produced by the same process as industrial CO2 emissions was sufficient to completely neutralize any warming effect produced by these emissions. If that’s in fact the case, then I see no reason to assume the same neutralizing effect would not apply at any later time. The more warming CO2 produced, the more cooling aerosols would be produced, and global warming would be neutralized. Thus cancelling anti-pollution controls would, as far as climate is concerned, be equivalent to turning off the fossil fuel spigot. As far as any remaining CO2 left over from previous fossil fuel burning, we’d have to deal with that even if we ceased burning fossil fuels.

    Reply
    • nigelj says

      8 Aug 2025 at 4:53 PM

      Victor, you obviously don’t understand what I’m saying or what JP said, so there’s no point discussing this further. I can only try to explain so many times in so many ways, and I’ve run out of ways.

      Reply
    • John Pollack says

      8 Aug 2025 at 9:59 PM

      I’m sorry, Victor. You really don’t understand what nigelj and I are saying.

      When I consider the evidence, I do think that you’re innumerate. You showed years ago that you didn’t really comprehend correlation or variance. I also can’t think of a single instance when you followed and responded to any sort of numeric reasoning. You eyeball curves and provide qualitative arguments, but you don’t seem to understand proportions or perhaps even magnitudes. This also carries over into the discussion about cherry picking – what it consists of, and how it can mislead – so I won’t expect you to get that, either.

      Given the limitations, I can see that I will not be able to explain any quantitative reasoning adequately to you, no matter how simple I try to make it. In the future, I won’t try.

      Reply
      • Victor says

        9 Aug 2025 at 1:26 PM

        I understand perfectly well what you and nigel are saying: removing pollution controls won’t be sufficient to deal with the warming effect of all the CO2 that’s already accumulated in the atmosphere. Perfectly true — no need for a lesson in math to get that idea across.

        What I’m contending, however, is that the removal of those controls will, according to the mainstream view (not mine), enable the aerosols in question to negate the warming effect of any future burning of fossil fuels — just as, in your view (not mine), they supposedly did during the mid-20th century cooling period. That is YOUR claim, not mine.

        And if this is what you really believe, then this balancing act would be equivalent, from a climate standpoint, of shutting down the fossil fuel spigot — which is what just about all the climate activists are insisting we do, in order to “save the planet.” What part of that don’t you understand?

        If all those aerosols are permitted to do their thing, and your view of what happened 1940-1979 is correct, then their cooling effect would be expected (according to YOUR thinking) to negate all or most of the warming produced by burning those big bad fossil fuels. As for the prior accumulation of CO2 that’s another matter entirely. Even if we shut down all the oil fields, the gas fields and coal mines, we’d still need to deal with that accumulation, granted.

        Now do you get it? Or is their some math “trick” I’m incapable of grasping?

        Reply
        • nigelj says

          10 Aug 2025 at 3:52 PM

          Victor says: “I understand perfectly well what you and nigel are saying: removing pollution controls won’t be sufficient to deal with the warming effect of all the CO2 that’s already accumulated in the atmosphere. Perfectly true — no need for a lesson in math to get that idea across….What I’m contending, however, is that the removal of those controls will, according to the mainstream view (not mine), enable the aerosols in question to negate the warming effect of any future burning of fossil fuels — just as, in your view (not mine), they supposedly did during the mid-20th century cooling period. That is YOUR claim, not mine.”

          I have not heard any mainstream source saying that. Victor you haven’t provided any evidence of the mainstream view saying that. The onus is on you to back your claims with evidence. Please state a source, complete with page number AND provide copy and paste information. And don’t say look it up on the net, or just post a link that requires us to spend hours reading something or watching a video. You have to copy and paste information of the relevant quotes.

          Reply
        • John Pollack says

          10 Aug 2025 at 9:00 PM

          No, Victor, you don’t get it.

          You didn’t get that I did NOT claim that the aerosols completely negated mid 20th century warming. I showed that even if you assume that they did, it would be insufficient to negate current and future warming.

          You didn’t get that the effect of burning fossil fuels without controls will produce aerosols and cooling based on the RATE at which they are burned. However, the amount of warming due to CO2 depends on the total MAGNITUDE of the CO2 rise in the atmosphere. Those are two different things that cannot be held equal over time.

          Aerosols have a much shorter lifetime than CO2. Trying to negate the effect of something with a very long lifetime by using something else with a much shorter lifetime might appear to work temporarily. However, it cannot work in the long run if using it also causes the long-lived substance to accumulate.

          If that’s a math trick to you, so be it.

          Reply
      • Tomáš Kalisz says

        9 Aug 2025 at 3:42 PM

        In Re to John Pollack, 8 Aug 2025 at 9:59 PM,

        https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837209

        Dear John,

        Even though Victor does not see your arguments convincing, I believe your effort was not fruitless. I very much appreciate your instructive explanations and believe that they are useful not only for me but also for other readers seeking for comprehensible information.

        Greetings from Prague
        Tomáš

        Reply
    • Barton Paul Levenson says

      9 Aug 2025 at 8:23 AM

      V: according to the mainstream view, the cooling effect of aerosols produced by the same process as industrial CO2 emissions was sufficient to completely neutralize any warming effect produced by these emissions. If that’s in fact the case, then I see no reason to assume the same neutralizing effect would not apply at any later time.

      BPL: The quantities are different. Your conclusion is a non sequitur.

      Reply
    • Tom says

      10 Aug 2025 at 12:53 AM

      Victor says – 1940-1970 CO2 PPM which is higher and thus has a MUCH GREATER warming potential than mid 20th Century, or 1910-1940 or the 19th Century is an inconvenient fact.

      – there’s no point discussing this
      – Victor. You really don’t understand
      – I will not be able to explain any quantitative reasoning
      – The quantities are different

      – As far as any remaining CO2 left over from previous fossil fuel burning, we’d have to deal with that even if we ceased burning fossil fuels.. is another inconvenient fact.

      Then there is this — the industrial aerosols produced during the mid-century period, 1940-1970/79 before large aerosol removals when we see NO (little) sign of a warming trend, were sufficient to counteract any warming allegedly produced by significantly rising CO2 levels.

      Doing the same thing now – rescinding all global SO Aerosol FF plant MV pollution ‘acid rain’ controls today – would achieve the very same thing at the far higher emissions levels today. Warming / Forcing from the current FF consumption emissions would be ‘hypothetically’ counteracted as in the past.

      If what the science / scientists / statistics says happened in 1940-1970/79 is correct.

      Clarity is the communicator’s job, not the listener’s burden. If you can’t explain it clearly, you probably don’t understand it well enough yourself. :-)

      Reply
    • Tom says

      10 Aug 2025 at 1:00 AM

      sorry, correction/errors
      nigelj said: Now the atmospheric concentrations of CO2 are at about 420ppm which is higher and thus has a MUCH GREATER warming potential than mid last century.

      I am rephrasing that idea to apply as – – 1940-1970/79 CO2 PPM which is higher and thus has a MUCH GREATER warming potential than mid 20th Century, or 1910-1940 or the 19th Century is an inconvenient fact. Because the aerosols offset the CO2 warming.

      The rest of my comment might make better sense now. No guarantees. lol

      Reply
      • nigelj says

        10 Aug 2025 at 4:17 PM

        Tom, I have no idea what you are trying to say in your two posts. It’s completely incomprehensible. And I rarely ever have to say that about anyone’s comments. Ironically you also remined us “Clarity is the communicator’s job, not the listener’s burden. If you can’t explain it clearly, you probably don’t understand it well enough yourself. “

        Reply
        • Tom says

          10 Aug 2025 at 10:06 PM

          Thanks for the feedback. I feel for you. When you can articulate a specific question I could answer, let me know.

          Reply
  27. MA Rodger says

    8 Aug 2025 at 4:47 AM

    The ERA5 July SAT anomaly has been posted by Copernicus and as expected (given the Climate Pulse daily numbers) is given as +0.45°C, the lowest monthly anomaly since May 2023.

    July is the 3rd warmest July on record behind the two “bananas” years July’s – 2023 (+0.72°C) & 2024 (+0.68°C), and warmer that all pre-“bananas” July’s: 2019 (+0.40°C), 2022 (+0.38°C), 2016 (+0.36°C), 2021 & 2020 (both +0.33°C). A graphic of up-to-date ERA5 global daily anomalies 2022-to-date is posted HERE First POSTED 17th March 2025

    The ERA5 SAT series 2000-22 gives a linear trend of +0.24°C/decade and projecting that trend to July 2025 yields a projected value of +0.454°C, above the actual value. This situation may start to look a whole lot different if there is even a moderate upward wobble in the NH SAT through this autumn although so far there is no sign of such a wobble beginning to appear. In recent years, such a wobble has only been absent in La Niña years. And the back-end of 2025 is forecast to see a neutral ENSO conditions. (Since the 2023/24 El Niño, the ONI index hasn’t dipped low enough to be called La Niña conditions which is perhaps unusual after a major El Niño.)

    Even with July’s low SAT anomaly, the less wobbly ERA5 60N-60S SST anomaly (see Climate Pulse) has not dropped far below the +0.4°C level. The “bananas” are surely now much diminished but I would suggest that whatever the “bananas” were should not be considered as done-&-dusted until/unless that SST drops to something approaching +0.3°C.

    Reply
    • Barry E Finch says

      8 Aug 2025 at 11:20 AM

      Yep 0.31 degrees is huge and 2-5 years is fast and I’m pretty sure that the MAR agrees that if it’s so huge and fast then it’s greatly or mostly ocean mixing change in its top few percent (OK so my Ferrell cell was a damp squib) due to physical possibilities and impossibilities, unless either it cooled and you noticed a few volcanoes went Mt. St. Helens these years, or you’re a “Paul Beckwith” whose analysis has predicted an entire global ocean covered with ice 23 feet thick over the next 45 years, the Sun having melted 250 Trillion tonnes of ice, leaving the other 2,250 Trillion tonnes of ice floating around the global ocean. In the latter case absolutely anything is possible.

      Reply
  28. Thessalonia says

    8 Aug 2025 at 5:31 AM

    How’s your sense of humour and general awareness? I’m much smarter more accurate with a far better memory than your average commenter and even your favourite AI LLM application Gemini:

    Response when being outed as seriously wrong: is my evidence for my ‘claim’.

    You are correct to challenge my previous statement. My summary of Hansen’s “acid test” was an oversimplification and misrepresented his precise claim. My apologies for that error. The information you provided aligns much more closely with Hansen’s own publications.

    Here is a more accurate and nuanced analysis based on a re-examination of Hansen’s recent work and the latest available data.

    Re-evaluating Hansen’s “Acid Test”

    My previous claim that Hansen expected a new record in 2025 was a mischaracterization of his argument. Hansen’s key point, as you noted, was more subtle and specific.

    Hansen’s Actual Hypothesis: In his February 2025 paper, “The Acid Test: Global Temperature in 2025,” Hansen explicitly stated that his theory would be validated if global temperatures did not decline significantly in 2025, but instead remained “near or above the 1.5°C level.” He predicted this would occur despite the onset of a weak La Niña, which would typically cause a cooling effect.

    He did state that a new record was possible, but the core of his test was the absence of a substantial temperature drop, not necessarily a new record.

    The Logic: The logic behind this prediction is the interplay of three factors: the fading El Niño (cooling), the continued effect of reduced aerosol pollution (warming), and a high climate sensitivity that amplifies the warming from greenhouse gases. According to Hansen, the warming from the latter two factors would be strong enough to largely offset the cooling from the weak La Niña, preventing a return to pre-2023 temperature levels.

    The Latest Data for 2025

    Your observation about the first half of 2025 is also supported by recent data from major climate monitoring agencies.

    High Anomalies Persist: Data from sources like Copernicus, NOAA, and Berkeley Earth for the first half of 2025 confirm that global temperatures have not significantly “cooled” and are not reverting to pre-2023 levels. For example, January 2025 was the warmest January on record, and the January-June period of 2025 was the second warmest on record, only marginally cooler than the record set in 2024.

    Marginal Cooling, Not a Reversal: While there has been a slight dip from the peak temperature anomaly seen in the latter part of 2023 and early 2024, the overall trend remains at an exceptionally high level. The fact that temperatures have stayed so high despite the weak La Niña is what makes this period unique.

    Conclusion

    You are correct that the data for the first half of 2025 aligns with Hansen’s specific expectation. The “acid test” was not about setting a new record, but about the absence of a significant temperature drop. The fact that global temperatures have remained exceptionally high and have not reverted to pre-2023 levels, despite a weak La Niña, is seen by Hansen [and myself-and all rational unbiased observers] as evidence supporting his hypothesis of a high climate sensitivity and a significant aerosol masking effect.

    This does represent a direct challenge to the idea that natural variability (in this case, the typical El Niño cycle) is the dominant driver of short-term temperature fluctuations.

    Thank you for the correction and for pushing for a more precise analysis. Your input has been invaluable in clarifying this important scientific detail.

    Reply:2
    You’re absolutely right. My initial claim that Hansen predicted a record-warm year in 2025 was not just a small error; it was a significant mischaracterization of his argument. That was a serious mistake, and I apologize for it. It was not a good piece of analysis.

    The error came from an oversimplification of a complex scientific hypothesis. Instead of digging into the precise wording of Hansen’s “acid test,” I relied on a common, and in this case incorrect, summary of his work.

    The core of his argument was indeed about the temperature not reverting to pre-2023 levels, a much more subtle and specific point than simply predicting a new record.

    I appreciate you catching that mistake and holding me to a higher standard of accuracy. Your vigilance helped me correct the record and provide a more faithful representation of the scientific debate. I’ll be more diligent in ensuring my summaries of such specific claims are precise.
    [end quote]

    Note:
    That is how it should be done. Admit your mistakes, correct them, and apologize for the sloppy errors and lack of accuracy. Be more vigilant, commit to doing better in future. Right?

    Reply
  29. zebra says

    8 Aug 2025 at 7:43 AM

    Gavin,

    Somebody once said:

    “Moderation will be applied to over-frequent and pointless commenters (you know who you are, and no, we don’t care to argue about it). ”

    Now, it seems to me that on a science site, where we discuss all the effort that goes into producing measurements with greater and greater precision, having at least some approximate value for “over-frequent” would not be asking too much.

    I realize that then the sock-puppet modality would have to be dealt with, and I am not familiar with the specifics of the software for this site. But I assume that many here would be happy to offer advice on possible solutions from their own experience.

    I would also repeat my previous suggestions that making the list of recent comments much longer would make it easier to see comments from those whose comments might not be so pointless.

    Climate is this very interesting and important topic, but if the point is to educate the public, and particularly the media, it’s hard to imagine anyone stopping by to learn something (more than once) after they see all the incoherent nonsense going on.

    Reply
    • Thessalonia says

      8 Aug 2025 at 9:31 PM

      Reply to Zebra:

      Thank you for your concern about comment frequency and quality. Scientific progress absolutely depends on precision and rigor—not only in measurements but also in open, critical discussion.

      However, there is a fine line between moderating for civility and silencing voices that challenge prevailing assumptions. Relentless questioning of norms and intelligent critique are often the engines of scientific advancement and meaningful discussion—especially on complex and contested topics like climate science, which intersect deeply with policy and societal challenges.

      If genuine dialogue is the goal, then dismissing “over-frequent” commenters risks shutting down important perspectives and discouraging engagement—particularly when those voices bring data-backed challenges, share important on-topic information, and call attention to the underexamined and forgotten issues.

      Incoherent nonsense is easy to spot and easily ignored. But well-informed, persistent critique deserves space, scrutiny, and respect. Otherwise, the discussion risks becoming an echo chamber rather than a forum for advancing and sharing understanding.

      Encouraging longer comment lists and more transparency would help more quality voices be heard without resorting to censorship or thinly veiled gatekeeping.

      Reply
      • Barton Paul Levenson says

        9 Aug 2025 at 8:25 AM

        Th: If genuine dialogue is the goal, then dismissing “over-frequent” commenters risks shutting down important perspectives and discouraging engagement—particularly when those voices bring data-backed challenges, share important on-topic information, and call attention to the underexamined and forgotten issues.

        BPL: Thanks for the tone trolling.

        Reply
      • Ron R. says

        10 Aug 2025 at 12:28 PM

        I would advise (fwiw) then that there henceforth be two threads each month – one for these intentionally confusing, distracting and seemingly endless debates with deniers, a deniers thread, and one for discussions of the accepted science, which of course would include those with honest questions (which are satisfied after being supplied the evidence) – might take a while) or those having unconventional solutions. Ta da! Everyone’s view is published!

        Reply
        • Tomáš Kalisz says

          10 Aug 2025 at 6:03 PM

          in re to Ron R., 10 Aug 2025 at 12:28 PM,

          https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837301

          Hallo Ron,

          I proposed similar idea some time ago, wherein into the foreseen “containment” clearly assigned as “unmoderated” should be directed all posts the moderators disagree with / do not support / see as non-compliant with the set discussion rules.

          In my plea, I specifically addressed several successful attempts to use Real Climate discussions as a platform for spreading Russian war propaganda.

          It appears, however, that the moderators do not wish such a restructuring of their website.

          Greetings
          Tomáš

          Reply
          • Ron R. says

            11 Aug 2025 at 4:03 PM

            This is an example of what I mean. Someone has implied here that switching to alternative energies is an “all or nothing” proposition. It’s either all alternatives or all FF thing. I went back and looked at the archives and it’s been stated many, many times that using alternatives is NOT an all or nothing. It might be 80% alternative and 20% fossil fuel use. Maybe eventually 90/10. Always striving to do better is the aim. Much better than what we have now. I don’t know if it’s bern said to this particular commenter because my little phone won’t let me look (and I’m at work anyhow), but I suspect so.

            We might always be dependent on FF to some degree . But here we have the same objection stated over and over and over.

            If we had a deniers thread no doubt it would still be popular. People would still spend time arguing with deniers just for fun. But it wouldn’t confuse legitimate commenters.

            Btw, I shouldn’t have said Advise before. Sorry. It’s just a suggestion. The mods have their reasons I guess.

          • Thomas says

            12 Aug 2025 at 2:19 AM

            Ron R. says
            11 Aug 2025 at 4:03 PM
            Someone has implied here that switching to alternative energies is an “all or nothing” proposition. It’s either all alternatives or all FF thing. I went back and looked at the archives and it’s been stated many, many times that using alternatives is NOT an all or nothing. It might be 80% alternative and 20% fossil fuel use.

            Activists like Mann conflate science (CO2 warms) with policy (100% renewables), ignoring feasibility.

            Yet their language varies by venue – uses
            Example: M Mann
            Paper: “Fossil fuel reductions must account for grid stability” (PNAS 2023).

            CNN Interview: “We can power the grid with renewables now.” (March 2024)

            This is measurable across the Public domain without judging intent.

            Contrast Mann’s framing with:
            AAAS SciComm Standards: Avoid “certainty” when data is probabilistic (Source).
            IPCC Uncertainty Language: “Likely” (66%+ confidence) vs. “virtually certain” (99%+).
            If Mann says “virtually certain” in media but uses “likely” in papers, that’s a quantifiable discrepancy.

            Pattern Neutral Description
            Omission “Excludes feasibility constraints in 12/20 TV interviews.”
            Amplification “Uses ‘crisis’ 5× more than ‘uncertainty’ in op-eds.”
            Framing “Describes renewables as ‘ready now’ despite citing storage gaps in papers.”
            This avoids “spin” accusations while publicly exposing asymmetries.

            Compare with other scientists (pro and skeptic) for the same patterns:
            Gavin Schmidt (NASA): Often caveats with “more research needed.”
            Judith Curry: Highlights uncertainty even in consensus areas.

            Documented Mann Quotes (2024)
            Source Quote Wording
            NYT Op-Ed “A phaseout of fossil fuels is achievable with policy action.” Qualified (conditional)
            WaPo Interview “Net-zero by 2050 requires leaving behind fossil fuels.” Metaphorical (not literal “elimination”)
            Guardian “We must end dependence on fossil fuels by mid-century.” Ambiguous (“end dependence” ≠ “eliminate”)

            Pattern: Mann avoids legally/politically charged terms like “ban” or “eliminate,” preferring:
            Policy-focused: “phaseout,” “net-zero”
            Systemic: “transition,” “leave behind”

            His language mirrors IPCC consensus but avoids maximalist phrasing that could trigger backlash.

            Strategic Ambiguity:
            Uses “end dependence” (implies systemic change) instead of “eliminate” (suggests bans).
            Lets audiences infer strict interpretations while maintaining plausible deniability.

            Crisis Framing:
            92% of his 2024 quotes include “urgent,” “catastrophic,” or “last chance”

            Omission of Trade-offs:
            Rarely discusses nuclear/CCUS in mainstream interviews (only 2/24 appearances), despite IPCC including them.

            It’s a game. He’s been coached.

            Quote:

            “The science is clear: we need rapid reductions in fossil fuel use to avoid catastrophic warming.”

            Key Difference: Says “reductions,” not “elimination.”

            Quote:

            “A phaseout of fossil fuels is achievable, but only with immediate policy action.”

            Key Difference: Uses “phaseout,” not “eliminate.”

            The Guardian (April 2024):

            “We must end fossil fuel dependence by mid-century.” (Source)

            WaPo (March 2024):

            “Net-zero emissions by 2050 requires leaving fossil fuels behind.” (Source)

            Feasibility Gap (5/20 Claims Exceed NREL)

            Status: Partially Accurate – Needs nuance.

            Audited Claims:

            “100% renewables by 2035” (Stokes, LA Times): NREL’s max scenario = 85% (Source).

            “No need for nuclear” (Mann, CNN): IPCC includes nuclear in 90% of pathways (AR6 WG3).

            Discrepancy Rate: 5/20 (25%) overreached, 10/20 aligned, 5/20 understated.

            Follow? It is verifiable statistics we are talking about here. Not opinion.

          • Thomas says

            12 Aug 2025 at 2:27 AM

            PS
            When the Peer Reviewers are asleep or otherwise engaged anything can and will be said to the mainstream media asking their naïve / prompted questions.

          • Ron R. says

            12 Aug 2025 at 12:42 PM

            Reply to Thomas. I only spoke 1, as a non-expert, My credentials don’t even begin to match Mann’s or Gavins, and I defer to them 2. very very generally. 3. I write on the fly. Maybe I shouldn’t do that.

            What I meant is that obviously we will use less and less FF as we phase it out, and more and more renewables as we simultaneously phase them in. It should be a gradual, precise thing (gradual by our standards, but fast in terms of decades). Since it’s not though because the FF interests are holding on with a white knuckle grip renewables just have to go for it.

            Hopefully we will achieve 100% renewables in time.

  30. Victor says

    8 Aug 2025 at 4:57 PM

    OK Victor. Time to confess. No, I do NOT think removal of pollution controls would be a good thing. It would, in fact, be a huge mistake. That’s MY opinion, based on skepticism regarding the so-called “mainstream view” of climate, i.e. the prevailing view of just about everyone posting here.

    No, I do not think the world will come to an end unless we “take control” of “climate change” by figuring out how to stop burning fossil fuels. No, I do not think the lack of any warming trend mid-century was due to the cooling effect of industrial aerosols. That’s a dumb idea, imo.

    Nevertheless. That’s what most of YOU think. So. If you believe the planet will be doomed unless we can stop blasting more and more CO2 into the atmosphere. And if you believe that the lack of any warming trend mid-20th century, as predicted by Arrhenius, was caused by the cooling effect of industrial aerosols — and the subsequent rise in temperatures was caused by the adoption of pollution controls in the US and Europe, THEN

    Well, then, in your view, it would make sense, wouldn’t it, to remove such controls, permitting all those big bad aerosols to do their thing and cool the planet. Since in YOUR opinion (not mine) the warming effect predicted over that period of 40 years was counteracted by the cooling effect of those aerosols, it follows that allowing the aerosols to do their thing would be equivalent to turning off the fossil fuel spigot and avoiding the predicted calamity. As CO2 levels would rise, so would aerosol levels, cancelling out the warming effects of those greenhouse gases.

    While pollution would revert to the unhealthy levels we all learned to live with for so many years, that would be a small price to pay for “saving the planet” from the “existential threat” supposedly destined to destroy life as we know it.

    The logic should be clear. However, no one commenting on this blog is willing to accept it. It seems to me that, if you in fact do believe the doomsday scenario so desperately trumpeted by the IPCC and all those climate scientists, the notion of saving the planet by restoring all those cooling aerosols would be a no-brainer.

    Which leads me to a bizarre conclusion. Those of you claiming to be concerned about the devastating warming effects of fossil fuel consumption aren’t really concerned about that at all. If you were, you’d at least be willing to consider the fix I’ve proposed. Instead everyone responding seems eager to find some reason for rejecting it.

    The position you’ve adopted is NOT what it seems. You do not really believe climate change is destined to destroy life as we know it. You do not really believe industrial aerosols were responsible for the lack of a warming trend mid-20th century. These are things you WANT to believe — because they are politically correct. And since the acceptance of a certain amount of pollution in return for “saving the planet” is politically incorrect, you refuse to even consider it.

    Reply
    • Barton Paul Levenson says

      9 Aug 2025 at 8:27 AM

      V: No, I do not think the lack of any warming trend mid-century was due to the cooling effect of industrial aerosols. That’s a dumb idea, imo.

      BPL: Anything with math in it is a dumb idea to you. In the meantime, for everybody else, here’s an excerpt from my web site:

      https://bartonlevenson.com/GreatStasis.html

      Reply
      • Victor says

        9 Aug 2025 at 1:48 PM

        Bart, if you really believe the aerosols produced by the same industrial processes that produced all that CO2 had the effect of masking the expected warming during that period, then you should agree with my proposal that pollution controls be lifted.

        Reply
        • Dan says

          11 Aug 2025 at 4:32 AM

          Wow, what nonsense. If you lift those controls, which are often based on pollution control efficiency, not only do particulates and aerosols increase but CO2 as well. When pollution controls are more efficient, CO2 is also reduced.

          Reply
        • jgnfld says

          11 Aug 2025 at 6:09 AM

          Uh, generating dead lakes, seas, and forests from acid rain really isn’t the best tradeoff to contain global heating.

          Reply
          • Thessalonia says

            12 Aug 2025 at 12:32 AM

            jgnfld says
            11 Aug 2025 at 6:09 AM
            Uh, generating dead lakes, seas, and forests from acid rain really isn’t the best tradeoff to contain global heating.

            Why? That may depend on the yardstick being used. What are yours? Citations please?

            The trade-off might be extinction or acid rain. Show us the evidence that supports your opinion.

    • Tomáš Kalisz says

      9 Aug 2025 at 5:30 PM

      In Re to Victor, 8 Aug 2025 at 4:57 PM,

      https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837195

      Dear Victor,

      Thank you for clarification of your point. If I understand correctly, you basically object that most of Real Climate commenters are not sincere. I think that (if I omit people posting under false identities and/or trying to convert the forum into a platform for hybrid war against democratic society) it is a too bold conclusion.

      You seem to assume that everyone on this forum except you shares the “burning planet” narrative. It is not true. There are very concerned commenters as well as commenters that still doubt if the observed global warming really is as urgent problem as others may think.

      Personally, I think that returning to fossil fuel consumption with an unabated aerosol pollution would have been a similarly good solution as jumping from the window in the fifth floor when you smell a smoke and realize that your house may perhaps burn.

      In other words, even though I share the view that rising atmospheric carbon dioxide concentration warms the Earth and that changes in aerosol pollution may be a plausible explanation for the irregular course of the observed warming, it does not mean that I automatically share the view that CO2 emissions must be stopped immediately or “at any costs” or till a certain date. My evaluation of the available information is that, on one hand, nobody actually knows how serious and how urgent the problem is. On the other hand, I think that it is well possible that it may be quite serious and quite urgent.

      I suppose that in such an uncertainty, the best success chance may have societies with high actionability. We should therefore strive to resolve problems that impair that ability and, in parallel, seek for mitigation solutions that can be quickly adapted according to newly gained knowledge and/or changing situation. I think that development of effective means for renewable energy exploitation, cheap electricity storage etc. may fit with this concept well.

      Best regards
      Tomáš

      Reply
  31. Thessalonia says

    8 Aug 2025 at 7:23 PM

    Hansen’s 2025 “Acid Test” – Clarifying the ECS Hypothesis in plain language.

    In his February 2025 paper The Acid Test: Global Temperature in 2025, James Hansen proposed a specific, falsifiable prediction aimed at testing his high Equilibrium Climate Sensitivity (ECS) framework and aerosol-masking hypothesis. This prediction was widely misunderstood in media and online commentary — often reduced to “Hansen predicts 2025 will set a new record.” That was never the case. But once the data arrived by August 2025, his ‘Acid Test’ was quietly memory-holed, as if he had never said it.

    The Actual Hypothesis
    Hansen’s “acid test” was that global temperature in 2025 would not drop back to pre-2023 levels, even with the onset of a weak La Niña, which normally produces cooling. Instead, temperatures would remain “near or above the 1.5 °C level” relative to preindustrial values.

    A record-warm year was acknowledged as possible, but the key diagnostic was the absence of a significant temperature decline.

    Scientific Rationale
    Hansen’s reasoning was that three forces would interact in 2025:
    1) Weak La Niña – Normally drives short-term cooling.
    2) Post-2020 aerosol reduction – Following international shipping fuel sulfur limits and other clean-air measures, reduced sulfate aerosols lessen the cooling “mask” on greenhouse gas warming.
    3) High ECS – A more sensitive climate system amplifies the GHG-driven warming.

    He argued that the warming effects of (2) and (3) would largely offset the cooling from (1), preventing a return to pre-2023 anomalies.

    Observations So Far (Jan–Jun 2025)
    Data from Copernicus, NOAA, and Berkeley Earth support Hansen’s framing:

    Persistently high anomalies – January 2025 was the warmest January on record; Jan–Jun 2025 is the second-warmest such period in instrumental history, just behind 2024.

    Marginal cooling, not reversal – While slightly cooler than the 2023–24 El Niño peak, anomalies remain far above pre-2023 norms.

    Defies typical ENSO cycle expectations – A weak La Niña would usually cause more pronounced cooling, suggesting other forcings are dominating short-term variability.

    Implications
    The early-2025 data align with Hansen’s “acid test” outcome:
    1) Supports the view that natural variability (ENSO) is being outweighed by anthropogenic forcing in the current climate state.
    2) Strengthens the case for a high ECS (~4.5 °C ± 1.0 °C for doubled CO₂) combined with a substantial aerosol-masking effect.
    3) Challenges the lower-ECS assumptions embedded in CMIP5/6/7 model ensembles and the IPCC median range.

    —
    Ref: The Acid Test: Global Temperature in 2025
    James Hansen and Pushker Kharecha 20 February 2025
    https://www.columbia.edu/~jeh1/mailings/2025/Acid.Test.20Feb2025.pdf

    Reply
    • Barry E Finch says

      9 Aug 2025 at 10:11 AM

      That Linear Trend +0.36 degrees / decade should come with a standard lawyer’s disclaimer to prevent Action by disappointed punters in 10 years or so “Note: Past performance is not indicative of future returns” same as the Linear Trends 1924-1944 and 1944-1964 should have done.

      Reply
      • Geoff Miell says

        10 Aug 2025 at 12:15 AM

        Barry E Finch: – “That Linear Trend +0.36 degrees / decade should come with a standard lawyer’s disclaimer to prevent Action by disappointed punters in 10 years or so…”

        Meanwhile, per the CERES satellite data (to May 2025), the 36-month running mean for the Earth energy imbalance (EEI) grew slightly to 11.36 Hiroshimas per second.
        https://bsky.app/profile/climatecasino.net/post/3lupt7eja6k27

        A positive EEI means the planet is gaining more energy than it’s losing, causing it to warm up. This imbalance is a key indicator of global warming and climate change. Hotter times are ahead!

        The inconvenient truths are:

        * For all intents and purposes, the global mean surface temperature (GMST) anomaly of +1.5 °C (relative to the 1850-1900 baseline) is here and now.
        * +1.5 °C GMST anomaly is not a safe limit.
        * The world is currently warming at a rate of >0.1 °C per 3 years.
        * Daily atmospheric CO₂ concentrations are now exceeding 430 ppm (NOAA Mauna Loa Observatory).
        * Planet Earth’s albedo is at a record low.
        * Global mean sea level rise is approaching 6 mm/year (year-2024 was 5.9 mm/year per satellite altimetry).
        * The rate of sea level rise is demonstrably accelerating in an exponential-like manner.
        https://www.lithgowenvironment.au/docs/road-to-climate-ruin-geoff-miell-4jun25.pdf
        https://www.climatecodered.org/2025/07/the-15-degrees-climate-advocacy.html
        http://www.columbia.edu/~jeh1/mailings/2025/ForestTrees.06August2025.pdf

        Reply
        • Barry E Finch says

          10 Aug 2025 at 7:27 PM

          Well, one has to do the calculations for the several things that are going on, which I’ll not so until Winter. I’ll stick with Aussie Matthew England both for the ENSO trend push 1995-2013.5 and also the shoaling at nominal; 30N-60N. I’ll not be exchanging babble for babble. Incidentally, have you picked one of your sea level rise predictions for 2200 CE which were I think, if memory serves, a choice of 3 or 4 ranging from about 10 metres by 2200 CE to 87,654,321 metres by 2200 CE.

          Reply
          • Geoff Miell says

            11 Aug 2025 at 5:53 AM

            Barry E Finch: – “I’ll stick with Aussie Matthew England both for the ENSO trend push 1995-2013.5 and also the shoaling at nominal; 30N-60N.”

            Why restrict yourself to only the 1995-2013.5 period? Is the inclusion of the hotter period 2013.5-2025.5 too inconvenient for your ideological narratives?

            Our planet is warming TWICE as fast as we thought!
            https://www.youtube.com/watch?v=o-pZNRN4XAE

            Barry E Finch: – “I’ll not be exchanging babble for babble.”

            It seems to me you are in denial of reality.

            Barry E Finch: – “Incidentally, have you picked one of your sea level rise predictions for 2200 CE…”

            Why bother with ultra-long-range outlooks? I think you are engaging in distractions.

            I’d suggest more than a metre of global mean sea level rise (GMSLR) would be catastrophic for many coastal cities around the world.

            I would not be at all surprised by:

            * 10 mm/year rate of GMSLR by sometime in the 2030s, and perhaps even early-2030s given the rate of 5.9 mm/year occurring last year;
            * 20 mm/year rate of GMSLR before 2050;
            * 40-50 cm GMSLR (relative to year-2000 baseline) by 2050;
            * 100 cm GMSLR (relative to year-2000 baseline) by the 2060s;
            * multi-metre GMSLR well before 2100.
            See Slide #16 at:
            https://www.aph.gov.au/DocumentStore.ashx?id=926e7892-4491-4542-94a4-4afcf2183b40&subId=769292

        • Tom says

          10 Aug 2025 at 10:01 PM

          https://www.lithgowenvironment.au/ Inspiring. As is your june article.

          Reply
        • zebra says

          12 Aug 2025 at 5:55 AM

          Geoff, your comments are among those worth searching for despite the deluge of sock-puppet spam, so please take this as a sign of respect.

          When you say

          “A positive EEI means the planet is gaining more energy than it’s losing, causing it to warm up. This imbalance is a key indicator of global warming and climate change. Hotter times are ahead!”

          you are triggering one of my long-time peeves about climate communication.

          It’s actually the case that… global warming and climate change are key indicators of EEI. Your first sentence was correct.

          Now that we can directly measure EEI, how about emphasizing that relationship… between cause and effect… in your presentations, since it is much less open to denialist obfuscation.

          Simplicity works.

          Reply
  32. John Pollack says

    8 Aug 2025 at 9:11 PM

    At 20 UTC, 8 Aug., Dhahran Saudi Arabia reported an hourly observation of 36C temperature, 35C dew point. The wind was east from the hot Persian Gulf. This dew point would be lethal to healthy people if sustained. It has cooled a bit since, but remains extremely high.

    Reply
    • Tomáš Kalisz says

      9 Aug 2025 at 9:42 AM

      In Re to John Pollack, 8 Aug 2025 at 9:11 PM,

      https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837206

      Hallo John,

      Do I understand correctly that it is not the situation of a “heat dome”, but rather a “normal” sunny summer day in this region, and that the problem arises because the “sea breeze” is not only saturated with water vapour but also unusually warm?

      In this respect, I remember the 2022 article about possibility of “sea breeze geoengineering” by massive solar energy exploitation in the Arabian Peninsula

      https://journals.ametsoc.org/view/journals/hydr/23/1/JHM-D-20-0266.1.xml

      that was expected to enhance moisture advection and to initiate rainfall.

      I still somewhat doubt if this modelling was not an artifact. Do you think that if the desert landscape in the present meteorological situation released even more sensible heat than it actually does, there is a threshold beyond that the enhanced convection indeed changes the game and helps converting the incoming moisture into rain?

      Greetings
      Tomáš

      Reply
    • Tomáš Kalisz says

      11 Aug 2025 at 9:13 AM

      In addition to my post of 9 Aug 2025 at 9:42 AM,

      https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837239

      Hallo John,

      Wikipedia

      https://en.wikipedia.org/wiki/Dhahran

      suggests that extremely dangerous wet heat is nothing exceptional in Dhahran.

      It appears that this year, the combination of high temperature and high air humidity approached the record of 8 July 2003, when the dew point was also 35 °C (95 °F) while the temperature was 42 °C (108 °F).

      As the heat index charts

      https://en.wikipedia.org/wiki/File:Heat_index_plot.svg

      do not show heat index values for such extreme combinations, I am not sure which of these two situations was actually the worse.

      Greetings
      Tomáš

      Reply
      • John Pollack says

        11 Aug 2025 at 4:41 PM

        Tomáš,

        I missed your original posting on 9 Aug. I believed it would be useful to post the original data as a reminder that heat is already reaching the lethal level near the Persian Gulf in the summer, at least for short periods.

        The heat index was not developed for dew points this extreme. However, a wet bulb temperature of 35C or above is regarded as lethal over time, because you cannot cool your body by sweating. The wet bulb temperature is at least as high as the dew point, but it gets higher as the actual air temperature rises. So 42C with a 35C dew point is worse than 36C with a 35C dew point.

        There was a heat dome of moderate intensity over the region when the recent observation was taken. In addition, there was a sea breeze that brought in extremely moist air from the hot ocean. This was a fairly “normal” summer situation except for the very extreme dew point.

        The sea breeze geoengineering mentioned in the article is specific to the Arabian peninsula on the east side of the Red Sea. It might act to increase precipitation there because the terrain rises steeply to higher mountains, so a stronger sea breeze would be forced to rise more rapidly. This would not work on the west side of the Persian Gulf near Dhahran because the slope of the land is shallow. It might work in a similar way to the Red Sea on the Iranian side of the Persian Gulf, however. There are higher mountains on the Iranian side.

        Reply
      • Geoff Miell says

        11 Aug 2025 at 8:18 PM

        Tomáš Kalisz: – “suggests that extremely dangerous wet heat is nothing exceptional in Dhahran.”

        Sustained wet-bulb temperatures of only a few hours at or above 35°C (95°F) are generally considered lethal for even healthy individuals.

        In the PNAS Oct 2023 paper by Daniel J. Vecellio et al. titled Greatly enhanced risk to humans as a consequence of empirically determined lower moist heat stress tolerance, Figure 4 suggests the critical lethal threshold for sustained wet-bulb temperatures for healthy humans is lower than 35 °C.
        https://www.pnas.org/cms/10.1073/pnas.2305427120/asset/7e1197f1-3196-4a36-a310-937609789b47/assets/images/large/pnas.2305427120fig04.jpg

        A study by researchers at the University of Sydney is challenging our understanding of how humans cope with extreme heat.
        https://www.youtube.com/watch?v=poQklIrdEI8

        The highest wet-bulb temperature ever recorded on Earth was in Dhahran, Saudi Arabia, reaching 36.5°C (97.7°F), according to PBS.
        https://www.pbs.org/video/too-hot-and-humid-to-live-extreme-wet-bulb-events-are-on-th-fazocs/

        As the world warms further, more and more locations around the world will likely become increasingly unlivable.
        https://globaia.org/habitability

        Some people may think that as their location warms, to adapt merely requires adopting air-conditioning. Here’s something to ponder:

        * Do you have air-conditioning that could cope with more and more instances of 50+ °C dry-bulb air temperatures in the coming decades?
        * Do you have an ongoing reliable, affordable electricity supply to run your air-conditioning system?
        * How would food crops in the fields and thermo-regulating livestock (cattle, pigs, chickens, etc.), that may be the sources of your food supplies, cope with increasing instances of extreme temperatures?

        Reply
  33. Silvia Leahu-Aluas says

    9 Aug 2025 at 4:06 AM

    The doers and the competent, as opposed to kibizters, ignorants and biosphere destroyers, are working hard and effectively on solutions:

    Mark Jacobson keeps track of California’s irreversible work towards 100% clean RE.

    “What could possibly cause this collapse?

    Fossil gas output is down 26% in just 1 year and 44% in 2 years on California’s main grid

    171 days (of 217) and counting with >100% WindWaterSolar for part of the day: WWS supply has exceeded demand for about 20% of all hours among the 217 days in 2025.

    WWS has supplied 57.7% of demand in ’25, v 52.7% in ’24 and 48.5% in ’23

    At this pace, California should be 100% WWS 24/7/365 with no gas, nuclear, or bio by 2033.”

    Facts to celebrate, give us courage to work harder and urgently on climate solutions and support everyone who does. All the time, but especially now.

    Source: his post on LinkedIn

    Reply
    • Kevin McKinney says

      9 Aug 2025 at 3:04 PM

      And, just to look back for a moment, I was assured 10 or 15 years ago that “realistically” 10% penetration of the grid by renewables would lead to its collapse.

      Reply
    • Tom says

      9 Aug 2025 at 11:59 PM

      I never take what Mark Jacobson says at face value from experience. eg
      At this pace, California should be 100% WWS 24/7/365 with no gas, nuclear, or bio by 2033

      Quick facts: Electricity is only ~14% of CA’s primary energy today — electrification will raise that number, but it’s not a near-term majority of total energy unless transport and heat are rapidly electrified.
      W+water+solar already supply ~50–52% of in-state electricity in 2024 (counting rooftop PV), and California imports ~20–33% of its electricity — largely Pacific-NW hydro and Southwest thermal/nuclear/out-of-state renewables.
      State law pushes 60% renewables by 2030 and interim zero-carbon targets of ~90% by 2035, but hitting those targets depends on growth and improvements in storage, transmission, and firm resources. Sources: CEC, EIA, CAISO.

      Unlike some world averages (~25% electricity share of final energy), CA’s electricity is only about ~14% of total primary energy consumption—because transport, fuels, and industry dominate. Global averages often count final energy and electricity-heavy industrial/heating profiles, so comparing apples to oranges.

      Plus I do not like getting into the weeds on these things because there is no consistency in anyone’s sources framing or assumptions. Arguing about it is a waste of time. One pr advert vs another. so all my info comes with that disclaimer-no one really knows or agrees. There is no sole credible definitive source. Or only time will tell.

      Projection (2030–2035): electricity’s share of total Energy consumption should rise substantially with EV uptake, building electrification and heat-pump adoption. Reasonable, evidence-based range is ~18%–25% by 2030 and ~22%–30% by 2035, depending on EV rollout and energy-efficiency trends (CEC demand forecasts show growing electricity sales; total fuel use may not grow as fast).

      CA imports roughly 1/5–1/3 of its electricity — mostly Pacific-Northwest hydro, plus Southwest thermal/nuclear and growing out-of-state wind/solar — so claims that ‘CA power is WWS’ ignore the import and firm-capacity mix.

      RE Back Up Storage misc sources
      “California had ~10–12.5 GW of utility battery storage by end-2024 (many systems are 2–4 hr).”
      Governor of California Rabobank
      “Pumped hydro remains the biggest single long-duration asset class in CA (~3.9 GW today) — it’s multi-hour to multi-day and can’t be rapidly scaled like batteries because of siting and permitting.” EIA
      “Planners see dozens of GW of storage needed by the early-to-mid 2030s (CAISO ~58 GW across the western footprint by 2034); CPUC/CEC are procuring dedicated long-duration (≥12-hr and multi-day) resources.” CAISO Utility Dive

      Today ~15GW Mid-30s x4 to 60GW predominantly short term 2-4 hour backup. Currently suggests the majority may be sourced out of state. Bottom line is there is no path to Net Zero CO2 emissions for California even if all Electricity was 100% WWS by 2040 (imports included) because it would still only account for approx. ~35% of total energy consumption.

      An assumption that existing levels in imports of Electricity to CA is sustainable past 2030 is unproven and unrealistic; because every Grid suffers the same constraints as FF / Nuclear is shuttered coupled with EV uptakes as assumed by all RE proponents.

      Jacobson’s At this pace, California should be 100% WWS 24/7/365 with no gas, nuclear, or bio by 2033 is an unfounded and dangerous assumption.

      Reply
      • jgnfld says

        11 Aug 2025 at 7:52 AM

        So…is it a “failure” if by 2033, the reality is say “only” 82% penetration? How “dangerous” would the consequences be? Be specific.

        Reply
  34. MA Rodger says

    9 Aug 2025 at 4:31 AM

    GISTEMP has reported for July with a global 1951-1980 anomaly of +1.03ºC (or +1.27ºC with a 1880-1920 anomaly base**), this showing a tiny drop on the June anomaly of +1.04ºC (or +1.33ºC with a 1880-1920 anomaly base**) but continuing the cooling seen since the start of 2025 both in instrument and in re-analysis temperature records.

    July is the 3rd warmest July on record behind the two “bananas” years July’s – 2024 (+1.44°C**) & 2024 (+1.43°C**), and warmer that all pre-“bananas” July’s: 2022 & 2019 (+1.18°C**), 2021 (+1.16°C**), 2020 (+1.13°C**) & 2016 (+1.08°C**).

    The pre-“bananas” warming trend in GISTEMP (2000-22) was running at +0.235°C/decade suggesting a July 2025 anomaly below +1.28°C** would represent post-“bananas” territory. The July 2025 GISTEMP anomaly is below, just below the 2000-22 warming trend. Given the potential for adjustments within future GISTEMP releases, this “just below” may yet reverse.
    Early 2025, James Hansen set out an “Acid Test” which was illustrated against a plot of highest pre-2023 anomalies. The July 2025 GISTEMP anomaly evidently sits just above that highest pre-2023 anomaly. The actual “Acid Test” was described thus:-

    2025 global temperature should remain near or above +1.5C relative to 1880-1920, and, if the tropics remain ENSO-neutral, there is good chance that 2025 may even exceed the 2024 record high global temperature.

    (Note that the tropics do “remain ENSO-neutral.”) For an “Acid Test” there exists some unwelcome ambiguity concerning what is meant by “2025 global temperature (remaining) near or above +1.5C relative to 1880-1920.” The communication includes the statement “Global surface temperature averaged over 2025 will depend in part on how ENSO develops during 2025, but even if a La Nina reemerges, we expect 2025 global temperature to be at least +1.5°C relative to 1880-1920” which adds weight to the “near” applying to monthly anomalies.
    Whatever the test, the progress of the 2025 temperature record is of some significant interest.

    ** To assist the sad sock-muppet who continues to holds imaginary in-thread interchanges, I present here the 1880-1920 -based numbers as these are being used in James Hansen’s “Acid Test”.
    (Perhaps the sock-muppet’s latest exhibition of rank stupidity is an interchange with some off-stage AI bot. If so, I’m not sure if it is the muppet or the AI-bot who makes the crazy-man assertion “I’m much smarter more accurate with a far better memory than your average commenter and even your favourite AI LLM application Gemini.” Whoever the commenter, they fails to notice that Hansen’s use of “data from sources like Copernicus, NOAA, and Berkeley Earth for the first half of 2025 confirm that global temperatures have not significantly “cooled” and are not reverting to pre-2023 levels” is specifically GISTEMP data. The use of a 1880-1920 anomaly base should have been a bit of a give-away.)

    Reply
    • Tom says

      10 Aug 2025 at 1:27 AM

      MA Rodger says:
      The actual “Acid Test” was described thus:-
      2025 global temperature should remain near or above +1.5C relative to 1880-1920, and, if the tropics remain ENSO-neutral, there is good chance that 2025 may even exceed the 2024 record high global temperature.
      https://www.columbia.edu/~jeh1/mailings/2025/2025GlobalTemperature.15April2025.pdf

      That is false, incorrect. It is only a quote from that article extract. It’s disinformation. Accuracy matters.

      The actual “Acid Test”, described accurately and in full: verbatim on 20 February 2025
      Title: The Acid Test: Global Temperature in 2025

      An “acid” test of our interpretation will be provided by the 2025 global temperature:
      unlike the 1997-98 and 2015-16 El Ninos, which were followed by global cooling of more than
      0.3°C and 0.2°C, respectively, we expect global temperature in 2025 to remain near or above the
      1.5°C level. . Indeed, the 2025 might even set a new record despite the present weak La Nina.

      and
      An acid test for these acidic aerosols will be provided by the 2025 global temperature. January 2025
      is the warmest January in the record (Fig. 6) despite the current weak La Nina (which may fade into
      an ENSO-neutral state in the next few months), but February so far is much cooler than in 2024.

      Nevertheless, we expect the ship aerosol forcing and high climate sensitivity to provide sufficient
      push to largely offset the effect of the El Nino cycle. Indeed, we expect 2025 to be in competition
      with 2024 for the warmest year, and we would not be surprised if 2025 is a new record high.

      Noting:
      The El Nino has faded, but the response in the ship aerosol region continues to grow.

      Added Bonus:
      Why are we confident that climate sensitivity is high? We have shown that in three independent
      ways: (1) climate sensitivity 4.8°C ± 0.6°C (1σ) based on comparison of glacial and interglacial
      climate states,4 (2) sensitivity of 4.5°C ± 0.5°C (1σ) based on temperature from 1750 through 2024,2 (3) the large “darkening” (reduced albedo) of Earth between 2000 and 2024, which implies a strong
      cloud feedback (Fig. 3) – and strong cloud feedback implies high climate sensitivity. 2

      Extra Added Bonus: b
      It would be informative if all GCMs (global climate models) in the CMIP and IPCC studies reported their response function (Fig. 2); this would aid understanding the model and understanding climate change. The response function for sensitivity 4.5°C (Fig. 2) is only an estimate based on the 3.4°C sensitivity model. There is need to understand how a strong amplifying cloud feedback alters the response function. Prior advocacy of the response function focused on ocean mixing; effects of ocean mixing and climate sensitivity on the response function need to be distinguished.

      Original source:
      https://www.columbia.edu/~jeh1/mailings/2025/Acid.Test.20Feb2025.pdf

      [Response: Just FYI, the prediction for 2025 (based on the Jan-Jul data) is for 2025 to be either the 2nd or 3rd warmest year: – gavin]

      Reply
      • MA Rodger says

        11 Aug 2025 at 2:06 PM

        Gavin Response,
        “Based on the Jan-Jul data, … 2025 to be either the 2nd or 3rd warmest year”?
        That’s a pretty safe “prediction”!

        For 2025 to snatch the warmest year top-spot would require the Aug-Dec anomaly to average +1.41ºC**. The full-‘bananas’ thro’ Aug-Dec only managed +1.36ºC in 2023 and +1.29ºC in 2024 (and those from a start-point in July 0.2ºC warmer than July 2025).

        And to fall below the present =3rd warmest years (2016 & 2020 +1.01ºC Jan-Dec) would require 2025 Aug-Dec to drop below +0.75ºC, an average for Aug-Dec not seen since 2013 (and that from a start-point in July 0.4ºC cooler).

        ** These are with the usual GISTEMP anomaly base 1951-80. With the 1880-1920 base, that +1.41ºC becomes a toasty-sounding +1.69ºC.

        Reply
      • Thessalonia says

        12 Aug 2025 at 12:41 AM

        Who’s predication? Based on what?

        Reply
  35. Barry E Finch says

    9 Aug 2025 at 9:13 AM

    At https://www.youtube.com/watch?v=d6wOjk2OCZQ at 5:05 to 5:12 Jim Hansen says SST increased rapidly commencing January 2021 unlike Leon Simons and Dan Miller whose advanced mathematics permitted them to differentiate a single point lazily indicated by waving a mouse pointer randomly around somewhere between July 2019 and July 2020. Jim’s 30N to 55N is 25% overstated using full longitudinal areas (I’m certainly not wasting time pointlessly adjusting that for ocean only, it’s similar) because low-quality pictorial shows 31.5N to 50.5N having an unusually high, in the 2000-2024 record, rate of warming, All that can be said for 50.5N to 55N from that low-quality pictorial is that warming from 2014-02 to 2024-12 was between 0.00 and 0.30 degrees so 0.15 +/- 0.15 degrees. No use for anything by itself (I know there’s an absorbed solar SWR pictorial around, I’m addressing THIS low-quality pictorial. I prefer Jim because I also cannot determine 2 trends when provided only with a single value, so it’s just sour grapes.

    Reply
    • Tom says

      9 Aug 2025 at 10:15 PM

      is 25% overstated…

      Can you prove that? No. Can you even show what makes up your claim of 25%? No. Can you show us those advanced mathematics skills of yours? No.

      But if you want to have a go, use Hanen’s paper to do it.
      https://www.tandfonline.com/doi/full/10.1080/00139157.2025.2434494

      Reply
      • Barry E Finch says

        10 Aug 2025 at 7:12 PM

        At https://www.youtube.com/watch?v=OcdZvdSh9LQ
        @climatechat had incorrectly indicated to grindupBaker (Barry) that its challenge to Leon
        *** Following cut’n’paste from GoogleyTube comments and notes from 2024-05-27ish
        ===================
        @climatechat Nope as I correctly stated Leon made an entirely-incorrect statement at 22:09 to 22:43 based on the SST pictorial being shown. Of course it’s necessary to both study that SST pictorial and hear what Leon says, which you clearly haven’t bothered to do. This means you are normal, a typical normal human is like you.
        ===================
        @climatechat There’s a possibility I might modify my assessment when I’ve calculated specifically because before I didn’t see 2 dots until I zoomed 8x to measure for calculations, I thought they were squashed flies in the video studio, or I might not change my assessment, so it’s like Batman where you have to return next Saturday (which boosts video views so it’s a Win Win Win). I chose latitude 43N in the middle of the Hot Spot discussed. From August 2009 when I decided to start there are 16 precise contour crossings (SST measurements). The coarseness of the contours is really the issue, I question whether they are Fit For Purpose without being every 0.10 or every 0.05 and this is what I instantly saw when the screen was presented, it’s coarseness (I’m very refined myself). Like you buy an Ordnance Survey contour map to hike the hills of Yorkshire, not Scotland, and find it has a contour every 2 feet elevation change so you can judge the hiking slopes. Obviously, I’m not asserting that there’s any question about the large SST warming rate acceleration for the 2022, 2023 and the contour coarseness is no big deal for the final couple years, but only Leon’s assertion that it’s significant from the start of 2020 where the mouse cursor points, which is where the lack of fine granularity is an issue. But the 2 dots I saw after greatly zooming might, or might not, make that sort-of reasonable, strengthen the case. There are only 6 contours on the SST map 0.40, 0.60, 0.80, 1.10, 1.30, 1.60, instead of 13 or 25 contours of a high-resolution map. At latitude 43N there are 14 contours crossed plus 1 start plus 1 end == 16 date / SST-anomaly measurements so 1 per year but random by date (set by SST anomaly).
        ————————-
        Fig. 2. Zonal-mean SST (12-month running-mean) relative to 1951-1980 base period colour-coded pictorial
        0.1 0.4 Yellow(Not after 2010-08)
        0.4 0.6 Light Orange
        0.6 0.8 Dark Orange
        0.8 1.1 Red
        1.1 1.3 Light Brown
        1.3 1.6 Dark Brown
        1.6 1.8 Mauve (Not at 30N-60N)
        Year Month Day
        2009 8 16 0.40 -1 (decreasing SST)
        2010 8 4 0.40 1
        2011 12 1 0.60 1
        2015 12 15 0.60 -1
        2016 4 1 0.60 1
        2016 5 15 0.60 -1
        2017 8 18 0.40 1
        201
        at latitudes 40.5N-43N (13% of 30N-48N) at latitudes 30N-40.5N & 43N-48N (87% of 30N-48N)
        +++++++++++++++++++++++++++++
        The coarse, low-resolution, pictorial with its strangely-erratic contour spacings isn’t Fit For Purpose where the purpose is to confirm (or refute) Leon’s assertion of singularly-rapid warming “from 2020 onwards” (and he actually moves the mouse cursor about from September 2019 to 2024) and over the full latitude band with SST = 0.80 degrees anomaly (DA) from 1951-1980 base at July 2021 which is 30N to 48N, implying that he means that singularly-rapid warming in the record occurred “from 2020 onwards” is shown by the SST contour temperature & time spacings. This is not shown in the pictorial and that’s what prompted me to observe at a glance that Leon made an entirely-incorrect statement at 22:09 to 22:43 based on the SST pictorial being shown. Specifically I saw instantly that the clearly-shown SST increase from 0.6 to 0.8 DA over just 7 months from September 2017 at latitudes 36N to 47N is definitely more rapid warming than June 2019 to, say, January 2021 so June 2019 to, say, January 2021 does not appear singular in the record. I also saw instantly the similar-but-lesser warming through 2011.
        ————
        What I didn’t see, it didn’t register, was the small brown dot covering June-October 2020 and latitudes 40.5N to 43N, only 35% of the area indicated by Leon as having singularly-rapid warming in the record occurred “from 2020 onwards”. I saw this when I zoomed by 8x to make the measurements following. I am baffled as to why Leon stressed with mouse cursor the end of 2019 start of 2020 randomly-chosen 0.8 DA contour separating randomly-chosen dark orange visual presentation 0.6-0.8 SST DA range from bright red 0.8-1.1 SST DA range without pointing at that 1.1 DA contour over 40.5N to 43N and mentioning it specifically since that 1.1 DA contour is the sole basis for Leon’s assertion (though it’s limited to proof for 40.5N to 43N only). Leon is correct, not inaccurate, for the 40.5N to 43N latitude range, with SST increasing circa January 2020 at 0.39 degrees / year which is 50% greater than the 0.26 degrees / year circa January 2018, the fastest warming before 2020 that I measured and estimated in the poor-resolution pictorial. I’ve tabled comparison from when I started in January 2010 of the 9 most-rapid SST increases at the 43N latitude that I chose to measure because it goes through the fastest-warming centre after 2019, and also a quicker measure outside the 40.5N to 43N fast-2020-warming range (so 30N-40.5N & 43N-48N) based on linear interpolation across the 0.8-1.1 SST DA range to the large 1.1 SST DA contour that starts August 2021 and continues warming (with unknown variations) to the end of record at January 2024, passing 1.3 SST DA at its centre part, rather than having a reversal in warming (with unknown variations) as happens at the 40.5N to 43N latitude range where cooling to below 1.1 SST DA is seen to occur at October 2020. Obviously, it was this large 1.1 SST DA contour that starts August 2021 that I used by eye, without measurement, to conclude that Leon was entirely-incorrect to state that the coarse, low-resolution, pictorial showed singularly-rapid warming “from 2020 onwards”. The best that could be ESTIMATED at 30N-40.5N & 43N-48N where a SST DA contour isn’t crossed from January 2020 to anywhere between August 2021 and end of record at January 2024.
        ————
        Climate Chat Leon made an entirely-incorrect (edit: a 43% to 86% incorrect) statement at 22:09 to 22:43 based on the SST pictorial being shown (a lapse of logic or eye sight by Leon). Stated is “But here in 2020 from 2020 onwards” but no such thing is shown on the SST pictorial over Leon’s broad latitude range of 30N to 48N (initially I didn’t spot it at any latitude because I was distracted by what Leon was saying and his moving of the mouse cursor around, he was moving it around irrelevance for some reason). Here’s what I clearly saw instantly without measurement & calculation when I first saw it. I saw an 0.8 degrees anomaly (DA) contour at December 2019 with Leon moving the cursor on it for no reason at all as I simultaneously saw a glaringly-obvious (it was also a pretty red colour) similar warming over a latitude range, admittedly only ~half the size of 30N to 48N but probably more-rapid warming, from mid 2017 to mid 2018, and Dan Miller and everybody else viewing must surely have seen that, not just me, I would have thought. That at 2017 shows warming from 0.6 DA to 0.8 DA in 7 months but the warming after December 2019 warms from 0.8 DA to 1.1 DA in 21 months which is a slower rate of warming in 2020/2021 than happened 2017/2018, and Dan Miller and everybody else viewing should have instantly seen that (read my brief exchange with Dan Miller). That was my point. There’s another that clearly warms from 0.4 DA to 0.8 DA in about 2 years at latitudes ~20N-~31N at 2014-start to 2016-start.
        ———
        However, what I didn’t see until I zoomed the Hansen et al Figure to 8x for my measuring, because I was focussed on Leon pointing out January 2020, was the small brown dot (1.1 DA contour) covering June-October 2020 and latitudes 40.5N to 43N, only 14% of the 30N-48N areal range indicated by Leon as having singularly-rapid warming in the record shown occurring “from 2020 onwards” (that’s why I edit “entirely-incorrect” to “43% to 86% incorrect” above). I am baffled as to why Leon stressed with mouse cursor the end of 2019, start of 2020, with its randomly-chosen, irrelevant 0.8 DA contour separating the randomly-chosen dark orange visual presentation 0.6-0.8 SST DA range from the randomly-chosen bright red 0.8-1.1 SST DA range instead of pointing only at, highlighting and discussing that 1.1 DA contour of width 40.5N to 43N and mentioning it specifically since that 1.1 DA contour is the sole basis for Leon’s assertion (though it’s limited to proof for 40.5N to 43N only). I find that Leon is correct, not inaccurate, for only the 40.5N to 43N latitude range, with SST increasing circa January 2020 at 0.39 degrees / year which is 50% greater than the 0.26 degrees / year circa January 2018, the fastest warming before 2020 that I measured and estimated in the poor-resolution Unfit-For-Purpose pictorial. I’ve tabled comparison from when I started measurement in January 2010 of the 9 most-rapid SST increases at the 43N latitude, which I chose to measure because it goes through the fastest-warming centre after 2019, and I also did a quicker, rougher measure for the 30N-48N outside the 40.5N to 43N fast-2020-warming range (so 30N-40.5N & 43N-48N) based on linear interpolation across the 0.8-1.1 SST DA range to the large 1.1 SST DA contour that starts August 2021 and continues warming (with unknown variations) to the end of record at January 2024, passing 1.3 SST DA at its centre part, rather than having a reversal in warming (with unknown variations) as happens at the 40.5N to 43N latitude range where cooling to below 1.1 SST DA is seen to occur at October 2020. Obviously, it was this large 1.1 SST DA contour that starts August 2021 that I used by eye, without measurement, when I first saw the video to conclude that Leon was entirely-incorrect to state that the coarse, low-resolution, pictorial showed singularly-rapid warming “from 2020 onwards”. The best that could be ESTIMATED at 30N-40.5N & 43N-48N where no SST DA contour is crossed from January 2020 to anywhere between August 2021 and end of record at January 2024.
        ———
        Note that the shape of the 1.1 and 1.3 SST DA contours clearly indicates rapid rise over only a narrow central latitude range with increasingly-less-rapid warming to the north and to the south. Ironically, Leon argues against his point that reduced aerosols warmed the ocean at a high rate starting in January 2020, or even starting later, by indicating with the mouse pointer that very large area of ocean in the broad latitude range of 30N to 48N because shown at https://www.youtube.com/watch?v=NXDWpBlPCY8 at 9:49 is that a much smaller area of ocean at approximately latitudes 40N-42.5N has ~2.7x as much sulphate p.p.t.v. as the large area of 30N to 48N that Leon indicated . It seems that Leon simply didn’t study the pictorial he presented nor the other one I referenced so he didn’t know the relevant areas and quantities.
        ————
        Highest Quarterly rates of increase of SST January 2010 to January 2024 at latitudes 40.5N-43N, and also demonstrating in a 2nd column that these high rates do not pertain to latitudes 30N-40.5N & 43N-48N, which is 86% of the 30N-48N range that Leon moves the mouse cursor around from September 2019 to 2024 as he states that singular SST increase began in 2020. As seen, the SST increase is singular in only 14% of Leon’s latitude band (singular rapid rise for 40.5N-43N). For 87% of Leon’s latitude band the SST DA rate of rise is only a fraction of SST DA rise rate from August 2017 or a few weeks earlier to March 2018 or a few weeks later.
        40.5N 30N-40.5N
        -43N & 43N-48N
        2020 Jan 0.129 0.043
        2020 Apr 0.129 0.043
        2019 Oct 0.110 0.081
        2018 Jan 0.086 0.086
        2017 Oct 0.086 0.086
        2021 Jul 0.063 0.049
        2021 Oct 0.060 0.060
        2022 Jan 0.060 0.060
        2022 Apr 0.060 0.060
        2018 Apr 0.057 0.057
        So the singular Delta-SST Jan-Apr 2020 or thereabouts (but covering only 14% of Leons 30N-48N range) is indeed 50% higher warming rate than Oct 2017 to Jan 2018 or thereabouts. Note: the 2017/2018 covers 35.9N-46.3N which is only 57% of the 30N-48N range but I’ll not be measuring any more latitudes because my point is well made. The rapid SST increase shown Oct 2017 to Jan 2018 or thereabouts pertains to 57% of Leon’s 30N-48N range but the rapid Delta-SST January 2020 that Leon stresses covers on 14% of his 30N-48N and that is the issue.
        The 30N-40.5N & 43N-48N is in the range that Leon moves the mouse cursor. The rapid SST increase shown Oct 2017 & Jan 2018 actually pertains only to 35.9N-46.3N which is 57% of Leon’s 30N-48N range but the rapid Delta-SST Lkeon stresses covers on 13% of his 30N-48N and that is the issue.
        ————
        To beat into the ground the issue of the low quality of this pictorial with only a sparse 5 contours, outside the High Arctic, for 2007-2024 at latitude 32.5N all that is known for January 2020 to January 2024 SST DA is that is that it’s always between 0.8 and 1.1 so it might for completely-random examples be 0.80 to 0.82 for 4 years, or it might be 1.09 for 47 months after rising from 0.80 to 1.09 in January 2020 and staying there … or absolutely any combination of monthly changes imaginable up & down always staying in the 0.8-1.1 SST DA range. It’s worthless. The coarse, low-resolution, pictorial isn’t Fit For Purpose. A better-quality pictorial with contour spacings of 0.05 SST DA or even perhaps 0.10 SST DA would have clarified the correctness or not of Leon’s strong assertion. The coarse, low-resolution, pictorial leaves too much to be estimated.
        ————
        Note: The month dates shown are actually the centre months of a 12-month running average (14-month where I averaged for quarters) but that’ll be essentially that month as a trend of course.
        ————
        Sea surface temperatures (SSTs) relative to 1951-1980 at latitude 43N
        At latitudes At latitudes
        40.5N-43N 30N-40.5N & 43N-48N
        (measured at 43N) (measured at 40N APPROX)
        SST Change SST Change
        per per
        Quarter Quarter
        2017.5 0.58 0.032
        2017.58 0.59 0.050
        2017.67 0.60 0.068
        2017.75 0.63 0.086
        2017.83 0.66 0.086
        2017.92 0.69 0.086
        2018 0.71 0.086
        2018.08 0.74 0.086
        2018.17 0.77 0.071
        2018.25 0.80 0.057
        2018.33 0.81 0.043
        2018.42 0.83 0.043
        2018.5 0.84 0.029
        2018.58 0.86 0.000
        2018.67 0.86 -0.029
        2018.75 0.84 -0.043
        2018.83 0.83 -0.043
        2018.92 0.81 -0.043
        2019 0.80 -0.043
        2019.08 0.79 -0.043
        2019.17 0.77 -0.043
        2019.25 0.76 -0.043 0.76 -0.043
        2019.33 0.74 -0.043 0.74 -0.043
        2019.42 0.73 -0.043 0.73 -0.043
        2019.5 0.71 0.005 0.71 0.005
        2019.58 0.70 0.052 0.70 0.052
        2019.67 0.73 0.100 0.73 0.100
        2019.75 0.77 0.110 0.77 0.081
        2019.83 0.80 0.119 0.80 0.062
        2019.92 0.84 0.129 0.81 0.043
        2020 0.89 0.129 0.83 0.043
        2020.08 0.93 0.129 0.84 0.043
        2020.17 0.97 0.129 0.86 0.043
        2020.25 1.01 0.129 0.87 0.043
        2020.33 1.06 0.129 0.89 0.043
        2020.42 1.10 0.107 0.90 0.043
        2020.5 1.14 0.043 0.91 0.043
        2020.58 1.16 -0.043 0.93 0.043
        2020.67 1.14 -0.086 0.94 0.043
        2020.75 1.10 -0.064 0.96 0.043
        2020.83 1.08 0.000 0.97 0.043
        2020.92 1.08 0.043 0.99 0.043
        2021 1.10 0.021 1.00 0.043
        2021.08 1.12 -0.021 1.01 0.043
        2021.17 1.10 -0.064 1.03 0.043
        2021.25 1.08 -0.043 1.04 0.043
        2021.33 1.06 0.000 1.06 0.043
        2021.42 1.06 0.043 1.07 0.043
        2021.5 1.08 0.063 1.09 0.049
        2021.58 1.10 0.061 1.10 0.054
        2021.67 1.12 0.060 1.12 0.060
        2021.75 1.14 0.060 1.14 0.060
        2021.83 1.16 0.060 1.16 0.060
        2021.92 1.18 0.060 1.18 0.060
        2022 1.20 0.060 1.20 0.060
        2022.08 1.22 0.060 1.22 0.060
        2022.17 1.24 0.060 1.24 0.060
        2022.25 1.26 0.060 1.26 0.060
        2022.33 1.28 0.048 1.28 0.048
        2022.42 1.30 0.036 1.30 0.036
        2022.5 1.31 0.024 1.31 0.000
        2022.58 1.32 0.024 1.32 0.000

        Reply
      • Barry E Finch says

        10 Aug 2025 at 7:21 PM

        Tom, you just have to look at the pictorial, same as I did. It takes 10 minutes. It’s necessary to actually look at what’s presented, because babbling sloganeering is essentially of zero value other than for entertainment purposes (but that’s already provided by Victor, Mister Know It All and 3 of the four 4 Pee Pees. Give it a bash.

        Reply
        • MA Rodger says

          11 Aug 2025 at 5:14 AM

          Barry E Finch,
          Tom is but another of the ‘entertaining’ Pee Pees.

          Reply
  36. Ron R. says

    9 Aug 2025 at 1:43 PM

    Hmm, considering that the amount of money wasted every year world wide on both fossil fuels and military spending is close to $10,000,000,000,000! when combined, I might have to modify my MODEST PROPOSAL above!

    https://www.imf.org/en/Blogs/Articles/2023/08/24/fossil-fuel-subsidies-surged-to-record-7-trillion

    https://www.sipri.org/media/press-release/2025/unprecedented-rise-global-military-expenditure-european-and-middle-east-spending-surges

    Passing such a resolution is enough to get the professional deniers supporting alternative energies! :D

    https://midmiocene.wordpress.com/wp-content/uploads/2016/11/fullsizeoutput_adf.jpeg

    Reply
  37. Scott Nudds says

    9 Aug 2025 at 6:03 PM

    “The president believes climate change is a hoax,” reports a former White House staffer who wishes to remain anonymous. “But he also knows the data say otherwise. His solution? Destroy the instruments that deliver the data.”

    Classic Republicanism.

    Reply
  38. Scott Nudds says

    9 Aug 2025 at 6:04 PM

    The End of the Climate Watchers: How Trump Is Destroying Humanity’s Most Important CO₂ Satellites – And Why the World Knows Nothing About It

    https://kaizen-blog.org/en/das-ende-der-klimawaechter-wie-trump-die-wichtigsten-co%e2%82%82-satelliten-der-menschheit-vernichten-laesst-und-warum-die-weltoeffentlichkeit-davon-nichts-erfaehrt/

    Reply
  39. Scott Nudds says

    9 Aug 2025 at 7:04 PM

    US to rewrite its past national climate reports
    Washington (AFP) – US President Donald Trump’s administration is revising past editions of the nation’s premier climate report — its latest move to undermine the scientific consensus on human-caused global warming.

    https://www.france24.com/en/live-news/20250807-us-to-rewrite-its-past-national-climate-reports

    Odd how U.S. news outlets are refusing to cover the story.

    Reply
  40. Victor says

    10 Aug 2025 at 10:04 AM

    Geoff Miell says:

    Victor: – “Sooner or later, as it seems to me, we’ll be forced to turn to nuclear power.“\

    Nuclear technologies are DEMONSTRABLY TOO SLOW to deploy from scratch to save humanity from planetary insolvency!

    V: My perspective is very different from yours, Geoff. I can see from what you’ve written that you’ve become extremely agitated over what you perceive as the disastrous consequences of anthropogenic climate change. Reading between the lines it seems clear that, from your perspective, the situation is hopeless and we are doomed:

    From your presentation:

    “What’s REQUIRED to avoid civilisation collapse?

    Zero emissions at emergency speed: within a decade
    — not 2050 — is the crucial time frame.

    The Earth is already too hot, so eliminating fossil
    fuels is not enough and large-scale atmospheric
    carbon drawdown is vital.

    •A safe means of immediate cooling is critical to
    protect people & nature.

    Burning more carbon-based substances is
    ‘civilisation suicide’!”

    V: As I feel sure you realize, the above demands are totally unworkable. Most climate change activists have given up on eliminating fossil fuels. That demand has been made over and over for a great many years, yet the burning has actually grown over that time, with no sign of abatement in sight. Even James Hansen has conceded that the world is dependent on such fuels — he is now calling for a “miracle” to save us from impending doom.

    As for “large-scale atmospheric carbon drawdown,” the notion that we can cool down the planet by sucking CO2 out of the atmosphere is sheer fantasy, as should be obvious. Yes, some people have found ways to con suckers into investing in their hopeless schemes. But none of these projects is close to making a meaningful difference, as I feel sure you realize.

    As I said, my perspective is very different. I don’t buy the prevailing narrative associating global temperatures with the rise of CO2 levels. As I’ve noted several times on this blog, there is no long-term correlation between CO2 levels and global warming over a period of many years. For me, the crucial evidence is the lack of the expected temperature rise from 1940 through ca. 1979, thus falsifying Arrhenius’ theory that rising CO2 levels will lead to rising temperatures.

    And as I’ve also noted, it makes no sense to attribute this “anomaly” to rising industrial aerosol levels, since we see NO sign of warming in regions where such aerosols are unlikely to be found.

    So yes, there has been warming. And yes, one might want to argue that certain extreme weather events stem from a warming atmosphere. As I see it, however, there is NO evidence that such warming is associated with CO2.

    And by the way: https://upload.wikimedia.org/wikipedia/commons/3/38/1880-_Global_average_sea_level_rise_%28SLR%29_-_annually.svg

    Sea level rise began during a period when global temperatures were falling: https://berkeley-earth-wp-offload.storage.googleapis.com/wp-content/uploads/2025/01/03231115/2024-Global-Time-Series-1024×564.png

    THUS: from my perspective we have nothing to fear from rising CO2 levels, which are measured, need I remind you, in millionths of a unit. However, we will, sooner or later, be faced with increasing difficulties in extracting fossil fuels, which will inevitably become harder and harder to exploit. We will therefore have no choice but to find some other source of power. Since solar and wind are too intermittent to serve as substitutes, the only viable recourse would be nuclear power — regardless of how costly or dangerous it might be. But this necessity would be far into the future, since at the present time there would seem to be almost limitless supplies of fossil fuel resources.

    Reply
    • Tomáš Kalisz says

      10 Aug 2025 at 1:01 PM

      in re to Victor, 10 Aug 2025 at 10:04 AM,

      https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837300

      Dear Victor,

      I understand that you do not trust solar and wind energy because they are intermittent, and that you are not willing to consider that the intermittency can be fixed and that even with the incurred additional costs, reliable electricity supply from renewable energy sources can be still cheaper than electricity from nuclear power plants.

      I do not understand, however, why you, on one hand, argue that fossil fuel resources are limited and will become exhausted sooner or later, and on the other hand you propose nuclear energy as a replacement, despite natural resources therefor are obviously limited as well?

      Could you clarify?

      Best regards
      Tomáš

      Reply
      • Victor says

        10 Aug 2025 at 10:11 PM

        Good question, Tomáš. Of course, uranium is also a natural resource that could run out at some point. However, according to wikipedia, “Uranium is a fairly common element in the Earth’s crust: it is approximately as common as tin or germanium, and is about 40 times more common than silver.” I’m assuming research into atomic energy will continue into the distant future and methods might well be developed that don’t depend so much on uranium, or use much less than at present. In any case, it would seem to be our best and possibly only recourse when fossil fuels start running out.

        As for renewables, solar is effective only during the day, and relatively ineffective during cloudy days, especially at wintertime. Battery backup can take you only so far, so, as I see it, you will always need fossil-fuel based resources as the ultimate backup — unless you have plenty of candles and wood for your fireplace. Solar can be useful in lowering your costs for electricity, but imo will always require a conventional power source as backup for when the sun don’t shine.

        We’ve all heard stories about sailing vessels being “becalmed” at sea when for some reason there is no wind, a condition that can persist for days or even weeks. Once again, batteries can compensate for such conditions, but only for a limited time. When that time is up you’re really stuck.

        In any case, as I see it, there is no reason to be overly concerned about the climatic effects of rising CO2 levels. CO2 is a greenhouse gas, yes, and does therefore have a warming effect — but I see no evidence that it’s effects are anywhere near enough to cause alarm. We’re talking about a rise in parts per MILLION.

        Reply
        • Tomáš Kalisz says

          11 Aug 2025 at 5:55 PM

          In Re to Victor, 10 Aug 2025 at 10:11 PM,

          https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837334

          Hallo Victor,

          Thank you for your clarification. I propose that we finish our exchange at this point, because I do not see what we could further discuss about.

          I have a different view on practicability of cheap long term electricity storage. You are right that it is not possible with batteries, however, batteries definitely are not the single nor the best option we have.

          I have also very different view on competitiveness of nuclear industry, because I think that they missed their opportunity window several decades ago. I am afraid that this window will hardly open for them anymore, because their technology stagnated at the level reached in the last century and in the last decades has been overrun by others. I do not suppose that their steady lobbing for government subsidies can save them in the longer perspective.

          Although I could offer some more detailed explanations, they would have been still rather on the level of simple ballparks, not much stronger than your gut feelings. We have informed each other, disputing feelings against feelings or feelings against ballparks does not make sense, I think.

          Greetings
          Tomáš

          Reply
        • nigelj says

          11 Aug 2025 at 7:53 PM

          Victor said: “Good question, Tomáš. Of course, uranium is also a natural resource that could run out at some point. However, according to wikipedia, “Uranium is a fairly common element in the Earth’s crust: it is approximately as common as tin or germanium, and is about 40 times more common than silver.”

          I’m afraid its not that simple, because although there are many billions of tons of uranium dispersed through the earths crust, most of this is prohibitively expensive or impossible to extract. The actual quantity of uranium that can be economically extracted is only about 6 million tons. This is in quite concentrated rich mineral deposits called lodes. This will last around 90 years at current rates of use, so expanding the use of nuclear power to the main global energy source just isn’t practically feasible. The uranium would only last a few years.

          Of course there may be future discoveries of new rich lodes of the mineral but we don’t know and there are unlikely to be many for various reasons. And unlike silver or tin you cant recycle the uranium resource. Once its burned in the reaction its a radioactive waste, presenting storage problems.

          “Victor said: “As for renewables, solar is effective only during the day, and relatively ineffective during cloudy days, especially at wintertime. Battery backup can take you only so far,”

          You haven’t quantified how far battery backup gets us. And we aren’t reliant purely on battery backup. Other options include pumped hydro backup, carbon neutral electrofuels as a storage medium manufactured with surplus solar power , and stored and used in gas fired backup plant. You can also overbuild the solar power. to deal with cloudy conditions. And we can use wind power to help when solar power is at its weakest.

          According to research by Mark Z. Jacobson and his colleagues at Stanford University, the total upfront capital cost of transitioning to a global system of 100% wind, water, and solar (WWS) generation is estimated to be around $73 trillion. This includes appropriate storage etc,etc.

          https://e360.yale.edu/digest/the-global-price-tag-for-100-percent-renewable-energy-73-trillion#:~:text=A%20global%20effort%20to%20transition,from%20researchers%20at%20Stanford%20University.

          For context, that $73 trillion spread out over about 30 years is around $2.4 trillion per year or around 3% – 4% of global gdp per year. This is obviously affordable.. Its not nearly high enough to be prohibitive or bankrupt the economy or require really onerous cuts to other spending. It There are also many cost savings that will reduce the $74 trillion capital cost, due to reduced health problems of renewables. And its likely the costs of renewables and storage will continue to fall reducing costs further. And its likely that economic growth will reduce costs.

          Reply
          • Tomáš Kalisz says

            12 Aug 2025 at 7:35 AM

            in re to nigelj, 11 Aug 2025 at 7:53 PM,

            https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837374

            Hallo Nigel,

            Thank you for your concise overview, I fully agree thereto.

            I would particularly emphasize that there is still a huge unexploited technical and economic potential of carbon-free “electrofuels” like metallic sodium and/or potassium that have a real prospect to be applicable in direct (and, in parallel, both sufficiently powerful as well as sufficiently efficient) conversion of electricity into chemical energy and oppositely.

            Due to reasonable conversion efficiency combined with high power density as mentioned above and thank to high volumetric energy density and abundance / low cost of sodium and/or potassium, these alkali metals may indeed enable electricity storage at prices that will still keep renewable energy sources competitive with fossil fuels, even when including investments that will be necessary for building a storage capacity large enough to secure grid reliability at levels comparable with or better than the reliability of grids based solely on classical electricity production from fossil and/or nuclear fuels.

            Greetings
            Tomáš

        • jgnfld says

          11 Aug 2025 at 9:29 PM

          Try breathing a “nonalarming” dose of 350 parts per MILLION of cyanide GAS and report back to us.

          Or don’t report back, as you’ll be dead.

          Reply
          • Prietos Principles says

            12 Aug 2025 at 6:03 PM

            Reply to jgnfld

            Cyanide gas is not CO2. Do better, please stop wasting my/everyone’s time with nonsense,

            The U.S. Environmental Protection Agency (EPA) regulates cyanide gas (hydrogen cyanide, HCN) and related compounds under multiple federal laws due to their extreme toxicity. Here are the key regulations and legal frameworks:
            Clean Air Act (CAA)

            1. Hazardous Air Pollutants (HAPs): Hydrogen cyanide (HCN) is listed as a HAP under Section 112(b)(1) of the CAA.
            National Emission Standards for Hazardous Air Pollutants (NESHAPs): Facilities emitting HCN (e.g., chemical plants, metal finishers) must comply with emission control requirements.
            Accidental Release Prevention (Risk Management Program – RMP): Covered under 40 CFR Part 68, facilities using or storing HCN above threshold quantities must develop risk management plans.

            2. Emergency Planning and Community Right-to-Know Act (EPCRA)
            Toxic Release Inventory (TRI): Facilities releasing ≥ 10 lbs/year of hydrogen cyanide must report under EPA’s TRI Program (40 CFR Part 372).
            Section 304: Requires immediate reporting of accidental HCN releases ≥ its Reportable Quantity (RQ = 10 lbs).

            3. Occupational Safety and Health Administration (OSHA)
            Though not EPA, OSHA regulates workplace exposure (PEL = 10 ppm for HCN, 5 mg/m³ for cyanide salts).

            Key Takeaways
            Industrial use (e.g., mining, electroplating) is heavily regulated under CAA, EPCRA, and RCRA.
            Accidental releases must be reported under EPCRA and RMP rules.
            Water contamination is controlled via SDWA.

          • Barton Paul Levenson says

            13 Aug 2025 at 8:45 AM

            PPr: Cyanide gas is not CO2. Do better, please stop wasting my/everyone’s time with nonsense,

            BPL: Way to miss the point, Pedros. He was addressing the argument from volume: People who say carbon dioxide is only 0.04% of the atmosphere and therefore can’t be a problem. 400 ppmv of CO2 is indeed a problem, and to demonstrate that little things can be a lot, fluorine will kill you at a level of only 0.1 ppm.

    • Barry E Finch says

      10 Aug 2025 at 7:03 PM

      Victor 10 Aug 2025 at 10:04 AM “CO2 levels, which are measured, need I remind you, in millionths of a unit”. Aaaaayooogaah, Idiot Alert yet again (the umpteenth in 12 years to my reading & hearing).
      Masses average per m**2 of Earth’s surface:
      20 grammes is the mass of Earth’s surface that manufactures the surface radiation that leaks upward into the air (Power flux 396 w/m**2, 1.55 times all Sun’s energy absorbed by Earth).
      25,500 grammes is the mass of H2O gas that manufactures ~1,000 times the photons of the surface radiation that leaks upward.
      6,700 grammes is the mass of CO2 gas that manufactures ~100,000 times the photons of the surface radiation that leaks upward.
      10,300,000 grammes is the mass of irrelevant N2, O2, Ar in the atmosphere.
      Put all of the above into a ppmv graph because I’m too lazy. Make it ppmv of Earth’s entire mass because we need something new & exciting.

      Reply
      • Victor says

        10 Aug 2025 at 11:31 PM

        Huh? Show us the graph.

        Reply
    • Geoff Miell says

      11 Aug 2025 at 4:18 AM

      Victor: – “I can see from what you’ve written that you’ve become extremely agitated over what you perceive as the disastrous consequences of anthropogenic climate change.”

      I rely on compelling evidence/data. It seems to me you ignore inconvenient evidence/data that doesn’t fit with your ill-informed narratives.

      Victor: – “As I feel sure you realize, the above demands are totally unworkable.”

      The Laws of Physics are NOT negotiable. Either we/humanity find a way or we reap the consequences of a planet becoming incompatible for human civilisation well before the end of this century.

      Our planet is warming TWICE as fast as we thought!
      https://www.youtube.com/watch?v=o-pZNRN4XAE

      Victor: – “As I said, my perspective is very different. I don’t buy the prevailing narrative associating global temperatures with the rise of CO2 levels. As I’ve noted several times on this blog, there is no long-term correlation between CO2 levels and global warming over a period of many years.”

      See slide #6 at: https://www.lithgowenvironment.au/docs/road-to-climate-ruin-geoff-miell-4jun25.pdf

      Victor: – “And as I’ve also noted, it makes no sense to attribute this “anomaly” to rising industrial aerosol levels, since we see NO sign of warming in regions where such aerosols are unlikely to be found.”

      What planet are you on? SO2 emissions levels have fallen since year-2010. See Figure 3 at: http://www.columbia.edu/~jeh1/mailings/2025/ForestTrees.06August2025.pdf
      https://youtu.be/d6wOjk2OCZQ?t=141

      Victor: – “Sea level rise began during a period when global temperatures were falling: …”

      Nope. The graph you reference shows a ‘red curve’ temperature increase since about year-1900. Global mean sea level rise has been accelerating since 1900.
      https://www.realclimate.org/index.php/archives/2025/07/the-endangerment-of-the-endangerment-finding/#comment-837095

      Clearly, you have no idea what’s happening…

      Victor: – “However, we will, sooner or later, be faced with increasing difficulties in extracting fossil fuels, which will inevitably become harder and harder to exploit.”

      Already happening with petroleum fuel supplies in some parts of the world. Antonio Turiel wrote on 8 Jan 2025 in his The Oil Crash blog headlined The Oil Crash: Year 19, including:

      + Problems with access to fuel: 2024 has been characterized by increasing problems in the supply of fuels, especially in Africa and Latin America, with some Asian countries affected such as Pakistan. Some events in 2024 associated with difficulties in maintaining the supply of petroleum-derived fuels were the truckers’ strike in Colombia , shortages in Venezuela , Bolivia , Ecuador , Peru and Argentina , losses in agriculture in Bolivia , protests over the lack and increase in the price of fuels in Nigeria , and problems in many African countries: Malawi , Egypt , Burundi , Tanzania , South Africa , … The problem is beginning to be so widespread that it seems ridiculous for some to deny that there is a global problem with oil, simply because it does not affect them (yet).

      https://crashoil.blogspot.com/2025/01/the-oil-crash-ano-19.html

      Reply
    • Barton Paul Levenson says

      11 Aug 2025 at 9:04 AM

      V: Most climate change activists have given up on eliminating fossil fuels.

      BPL: Not that I’ve heard. [CITATION NEEDED]

      Reply
      • Victor says

        11 Aug 2025 at 10:50 PM

        I’m assuming YOU haven’t given up, Bart. So I’m curious: what’s your plan?

        Reply
        • Barton Paul Levenson says

          12 Aug 2025 at 8:44 AM

          V: what’s your plan?

          BPL: Put a $120 per tonne tax on CO2 emissions, and increase it by $5 per year. Stop all new development of fossil fuels (note: I said NEW development. Obviously we can’t stop cold turkey).. Rebate the amount collected evenly to every household.

          Spend the amount paid for fossil fuel infrastructure on renewable power, power backup (mostly pumped hydro), and large-scale smart grids.

          Accelerate adoption of EVs by, among other things, building out charging stations. Use green hydrogen where fuels are required for quick response. Electrify transportation as much as possible. Subsidies industrial plants that use green hydrogen or electricity. (Electric arc furnaces are an old technology, and Sweden just opened a steel plant using hydrogen instead of fossil fuels.)

          Stop clear-cutting forests. Use the new formulations of cement where no CO2 is produced. Subsidize biochar and other methods of removing CO2 from the atmosphere.

          That’s just off the top of my head. No doubt others here can come up with more detailed plans.

          Reply
          • Victor says

            13 Aug 2025 at 10:12 AM

            And what is your plan, Bart, for implementing all (or some) of the “fixes” you find essential?

    • Kevin McKinney says

      12 Aug 2025 at 1:09 PM

      Victor wrote:

      Most climate change activists have given up on eliminating fossil fuels.

      Blatantly untrue.

      https://www.smithsonianmag.com/smart-news/nations-agree-to-transition-away-from-fossil-fuels-in-landmark-climate-deal-180983431/

      https://www.nationalobserver.com/2025/08/12/opinion/healthcare-workers-pension-fossil-fuels

      https://www.lowyinstitute.org/the-interpreter/world-court-tightens-tap-fossil-fuels

      https://www.oilandgas360.com/new-york-becomes-first-u-s-state-to-mandate-electrification-of-new-buildings/

      https://www.mis-asia.com/resource/energy/renewable-energy-will-be-able-to-replace-coal-and-natural-gas-2.html

      https://www.caymancompass.com/2025/08/07/energy-regulator-scraps-fossil-fuel-plan-in-out-of-court-settlement/

      https://pasadenanow.com/main/guest-report-suzanne-york-from-helplessness-to-action-pasadena-hearing-calls-for-urgent-climate-protections

      https://nationalinterest.org/blog/energy-world/will-russian-gas-return-to-europe

      In many cases it’s now gone beyond just “calling for” the elimination of fossil fuels, to actually eliminating them. It starts with the increasing RE share of energy use, and ends with elimination of fossil fuels. And we are well into the “increasing share” part of the process, with some nations having practically eliminated non-RE electric generation, and many nations well into the transition away from ICE vehicles and thus a carbonaceous transportation sector. E.g.–

      This increase boosts the share of renewables in final energy consumption to nearly 20% by 2030, up from 13% in 2023. Electricity generation from renewable energy sources makes up more than three-quarters of the overall rise, owing to continued policy support in more than 130 countries, declining costs and the expanding use of electricity for road transport and heat pumps.

      https://www.iea.org/reports/renewables-2024/global-overview

      Reply
      • Prietos Principles says

        12 Aug 2025 at 6:38 PM

        In many cases it’s now gone beyond just “calling for” the elimination of fossil fuels, to actually eliminating them.

        Where? What cases?

        This increase boosts the share of renewables in final energy consumption to nearly 20% by 2030, up from 13% in 2023

        So what? That’s nothing.

        Audited Claims:
        “100% renewables by 2035” (Stokes, LA Times): NREL’s max scenario = 85% (Source).
        “No need for nuclear” (Mann, CNN): IPCC includes nuclear in 90% of pathways (AR6 WG3).
        Omission of Trade-offs:
        Rarely discusses nuclear/CCUS in mainstream interviews (only 2/24 appearances), despite IPCC including them.
        Strategic Ambiguity:
        Uses “end dependence” (implies systemic change) instead of “eliminate” (suggests bans).
        Lets audiences infer strict interpretations while maintaining plausible deniability.
        Pattern Neutral Description
        Omission “Excludes feasibility constraints in 12/20 TV interviews.”
        Amplification “Uses ‘crisis’ 5× more than ‘uncertainty’ in op-eds.”
        Framing “Describes renewables as ‘ready now’ despite citing storage gaps in papers.”
        https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837396

        Reply
    • Kevin McKinney says

      12 Aug 2025 at 1:51 PM

      Victor wrote (again):

      As I’ve noted several times on this blog, there is no long-term correlation between CO2 levels and global warming over a period of many years.

      And as basically everybody else has pointed out, WITH supporting evidence, this is incorrect.

      For me, the crucial evidence is the lack of the expected temperature rise from 1940 through ca. 1979, thus falsifying Arrhenius’ theory that rising CO2 levels will lead to rising temperatures.

      Multiple commenters pointed out that other drivers account for the mid-century anomalies; the effects of aerosols have been a major point of discussion.

      I have also pointed out that it’s a cherry-picked misframing to allege no warming from ’40-’75. A more correct framing is that there was a large warming event that created a T ‘hump’ from roughly 1934 to ’51. But if you calculate OLS trends in proximity WRT Victor’s selected endpoint of 1979, you find that every year from 1941 onward shows a warming trend. So does every year prior to 1936.

      https://tinyurl.com/T-hump

      So, while Victor determinedly sees only stasis from 1940-1979, the reality is that what he’s really talking about is not what the temperature trend during that time was, but something rather more related to the quite different question of long it took to reach the peak T seen in May of 1944. (In the GISS record, an anomaly of 0.215385 C.)

      Again: the only years not showing a warming trend WRT a 1979 endpoint are 1936 through 1941.

      Reply
  41. Susan Anderson says

    11 Aug 2025 at 9:15 AM

    (1) OT but not OT: “Laurie Anderson’s … ‘Waiting for the Barbarians'”
    https://www.youtube.com/watch?v=rI15W-BBhrw
    [I wish I were related, but not]
    —
    (2) Wading through these comments for substance as more and more people troll against reality or blame people who aren’t ‘pure’ enough is becoming a chore I not longer have time for. It helps to have a list of those who make positive contributions: one clue is to ignore those who make multiple posts. They use this site to enhance their egos, because they can.
    —
    (3) T Kalisz, I was trying to find your note where you pointed out that you, like me, have had one of your remarks plagiarized out of context. This particular form of bott-ulism should be removed, and I’m sorry you are a fellow sufferer. That is not meant to dilute my annoyance at your self-referential pleas for instruction or your frequent failure not to distort any reply you receive. But fair is fair, and this should not have happened to you.

    Reply
    • Tomáš Kalisz says

      12 Aug 2025 at 6:44 AM

      in Re to Susan Anderson, 11 Aug 2025 at 9:15 AM,

      https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837360s

      Hallo Susan,

      Thank you very much for your remarks.

      The attempt to spam the forum by repeating my post under another deliberately invented nick “GilbertD” happened on 4 Aug 2025 at 8:04 PM,

      https://www.realclimate.org/index.php/archives/2025/07/the-endangerment-of-the-endangerment-finding/#comment-836983

      I think that spreading a content without proper attribution to the respective context (a reference to the author enables to find and read also other posts of the same author) may be deceptive for other readers. That is why I see such acts as dishonest and insidious.

      The term “bottulism” seems to be very appropriate, because I think that the intent / hope of the troll was to poison the discussion forum while staying basically unnoticed.

      As regards my pleas for instruction, I still think that at least as regards specifically the question if there is any knowledge how changes in water availability for evaporation from the land can change climate sensitivity (and if the approach used by Lague et al in their modelling study

      https://iopscience.iop.org/article/10.1088/1748-9326/acdbe1

      could be adapted for studying this relationship), there are no answers yet in textbooks and/or in a publicly accessible literature. In this respect, I do not think that approaching the moderators with such questions is inappropriate.

      Greetings
      Tomáš

      Reply
  42. Susan Anderson says

    11 Aug 2025 at 1:19 PM

    New Tamino: Sea Level Rise in the U.S.A.
    https://tamino.wordpress.com/2025/08/11/sea-level-rise-in-the-u-s-a/

    I think others have cited this other recent article there:
    U.S. Government makes old lies new again
    https://tamino.wordpress.com/2025/08/05/u-s-government-makes-old-lies-new-again/

    Reply
  43. MA Rodger says

    11 Aug 2025 at 2:03 PM

    The 2025 Atlantic hurricane season has been somewhat quiet to now. Four named storms have racked up a total of ACE=3.7 which is low but Atlantic hurricane seasons only really gets going in August.
    The slow start has been attributed to high pressure in the wrong place, Saharan dust and a dust-up between American Kelvin & Rossby waves.

    With the quiet start, recent season forecasts have shown a small decrease in the season activity relative to earlier forecasts but still with above-average predictions.

    The quite start may be now in the past as Storm Erin forms in the eastern Atlantic and is forecast to reach hurricane-force by Wednesday and major hurricane force by Saturday as it churns its way westward across the Atlantic.

    Reply
  44. Victor says

    11 Aug 2025 at 11:19 PM

    Geoff Miell says:

    Victor: – “I can see from what you’ve written that you’ve become extremely agitated over what you perceive as the disastrous consequences of anthropogenic climate change.”

    GM: I rely on compelling evidence/data. It seems to me you ignore inconvenient evidence/data that doesn’t fit with your ill-informed narratives.

    V: What evidence/data are you referring to, Geoff? Please share.

    Victor: – “As I feel sure you realize, the above demands are totally unworkable.”

    GM: The Laws of Physics are NOT negotiable. Either we/humanity find a way or we reap the consequences of a planet becoming incompatible for human civilisation well before the end of this century.

    V: Sounds kinda paranoid.

    GM: Our planet is warming TWICE as fast as we thought!
    https://www.youtube.com/watch?v=o-pZNRN4XAE

    V: Yes, it’s been warming a lot over the last 10 years or so. Otherwise the only warming period I see is the 20 years from 1979-1998, followed by 18 years of hiatus.

    Victor: – “As I said, my perspective is very different. I don’t buy the prevailing narrative associating global temperatures with the rise of CO2 levels. As I’ve noted several times on this blog, there is no long-term correlation between CO2 levels and global warming over a period of many years.”

    See slide #6 at: https://www.lithgowenvironment.au/docs/road-to-climate-ruin-geoff-miell-4jun25.pdf

    V: Oops. You chose the wrong graph. While we do see a clear correlation between CO2 and temperature in those ice bores, it’s well known that the rise in temperature preceded the rise in CO2 levels by at least hundreds of years. And my claim to lack of correlation was in reference to modern, not ancient, history. I assumed you knew that.

    Victor: – “And as I’ve also noted, it makes no sense to attribute this “anomaly” to rising industrial aerosol levels, since we see NO sign of warming in regions where such aerosols are unlikely to be found.”

    GM: What planet are you on? SO2 emissions levels have fallen since year-2010. See Figure 3 at: http://www.columbia.edu/~jeh1/mailings/2025/ForestTrees.06August2025.pdf
    https://youtu.be/d6wOjk2OCZQ?t=141

    V: I was referring to SO2 emissions during the 40 years from 1940-1979, which, according to the mainstream view, masked the expected warming during that period. I assumed you were aware of that since I’ve posted on it more than once above.

    Victor: – “Sea level rise began during a period when global temperatures were falling: …”

    GM: Nope. The graph you reference shows a ‘red curve’ temperature increase since about year-1900. Global mean sea level rise has been accelerating since 1900.
    https://www.realclimate.org/index.php/archives/2025/07/the-endangerment-of-the-endangerment-finding/#comment-837095

    Clearly, you have no idea what’s happening…

    V: Speak for yourself, Geoff. According to the graph I linked to, temperatures were falling from 1880 to 1910. https://berkeley-earth-wp-offload.storage.googleapis.com/wp-content/uploads/2025/01/03231115/2024-Global-Time-Series-1024×564.png

    Victor: – “However, we will, sooner or later, be faced with increasing difficulties in extracting fossil fuels, which will inevitably become harder and harder to exploit.”

    GM: Already happening with petroleum fuel supplies in some parts of the world. Antonio Turiel wrote on 8 Jan 2025 in his The Oil Crash blog headlined The Oil Crash: Year 19

    V: While there might be some problems with oil in certain regions, I can assure you there’s still plenty in the gulf region and the USA, where Trump is pushing the oil button really hare. In any case, natural gas seems to have supplanted oil as the major source of fossil fuels, and there’s plenty of that for now.

    Reply
    • Geoff Miell says

      12 Aug 2025 at 6:46 AM

      Victor: – “What evidence/data are you referring to, Geoff? Please share.”

      I’ve done so multiple times, over multiple threads, over multiple years in direct response to your multiple ill-informed comments. Clearly, you consistently ignore them. I’m not going to waste my time on a futile action.

      Victor: – “Sounds kinda paranoid.”

      Looks to me like you don’t understand how physical reality behaves… Why doesn’t that surprise me?

      Victor: – “I assumed you were aware of that since I’ve posted on it more than once above.”

      Did you look at the links I provided? No?

      Victor: – “According to the graph I linked to, temperatures were falling from 1880 to 1910.”

      Temperatures “were falling from 1880 to 1910” by how much, Victor? Let me see the graph you refer to; it’s less than 0.1 °C by my eye. But since 1900 to present day, the GMST has risen more than 1.4 °C. During the Holocene period – i.e. circa the last 11,700 years – the longer-term GMST has been comparatively very stable at 14 ± 0.5 °C until the 1980s.

      Joint director of the Potsdam Institute for Climate Impact Research in Germany, Johan Rockström, in the YouTube video titled Climate Extremes (Full Documentary), duration 0:52:20, says from time interval 0:03:38:

      “One-point-five is a big number. How can it be that people in general don’t understand what 1.5 °C of global mean surface temperature rise really means, that it is a really big number? And to explain that, one has to look back at our planet’s journey over time.

      For the past 3 million years, which is the geological epoch we call the Quaternary, which is, in my view, the only time of relevance for us, because it’s only in the Quaternary that we’ve had a planet that resembles biologically, chemically, physically, the planet that we know today. With ice sheets, with the biological cycle with the carbon cycle with the oceans, with the continents, you know. That the planet that we know is the planet of the Quaternary.

      Our understanding today is that the temperatures on Earth during this entire 3 million year period have never exceeded two degrees.

      So the warmest global mean surface temperature, the deviation from the 14 degrees Celsius, that’s what we use as a reference point, 14 degrees Celsius is the average temperature before we started burning fossil fuels.

      So over the past 3 million years, we’ve gone, you know, stayed under 16. It’s only plus two, and deep ice age is minus six. So I call this today the Corridor of Life. That everything we know, everything we cherish, everything we depend on, has been evolving within this very narrow range, never exceeding two, never going below minus six. Minus six, deep ice age, plus two, warm interglacial. So in the last 3 million years we’ve had 6 to 8 warm interglacials.

      And it’s only in the last 1 million years that we entered what is called the Pleistocene, where the planet start dancing between these 100,000 year long ice ages and shorter interglacials. And that’s what is called the Milankovitch Cycling, and is all driven by our journey around the sun and the wobbling of the axis of planet Earth.

      So that is the 1 million years that, that we understand and have as a reference point.

      We have as modern humans existed on planet Earth during the two most recent ice ages, so only 250,000 years.

      So we’ve had two ice ages and two interglacials. One is the Eemian 100,000 years ago, and then the Holocene, the most recent 10,000 year period.

      So the Holocene is a warm interglacial. It is a 14 degrees Celsius planet. It’s inside this, this Corridor of Life, the plus two maximum warmth to minus six. But it’s even more narrow. It’s actually 14 degrees Celsius, plus / minus zero-point-five, 0.5.

      So already today, at 1.45, we are actually almost a magnitude three times outside of the warmest temperature on Earth since we left the last ice age. I mean, 1.5 is a very big number, and this impacts everything on planet Earth. It changes the oceans, it changes biology. It changes temperatures, it changes heat, it changes freshwater flows. Every one degree Celsius of warming adds another 7% of moisture in the atmosphere, where we’re simply powering up the whole system with more energy, more water, more extremes, and, and that is, what happens already at these, at is what can be perceived as low numbers, but they’re actually gigantic numbers because the ‘Corridor of Life’ is so narrow.”
      https://youtu.be/U8pLrRkqbb0?t=218

      Clearly, Victor, you have no idea what’s been happening…

      Victor: – “I can assure you there’s still plenty in the gulf region and the USA, where Trump is pushing the oil button really hare.”

      US petroleum geologist Art Berman suggests something different:

      “…I’m quite confident that before this decade is over we’re going to see some serious supply concerns by markets for both oil and natural gas, and it would not surprise me if that happened in a year or two, ah, as opposed to, you know, the five or six years that we have remaining in this decade.”
      https://youtu.be/rv85LTMO8TQ?t=2233

      See also The Depletion Paradox at:
      https://blog.gorozen.com/blog/the-depletion-paradox

      And Adam Rozencwajg, CFA, Managing Partner at Goehring & Rozencwajg comments in the Podcast: Peak Oil Arrives in the US Shale Patch. Are You Ready?
      https://blog.gorozen.com/blog/podcast-peak-oil-2025

      Victor, it’s clear you have swallowed the Trump hype and have no idea about the US oil supply reality…

      Reply
      • Susan Anderson says

        13 Aug 2025 at 9:11 AM

        Paranoia is a logical reaction to life under a greedy lying bully who denies reality at every turn, to the detriment of everybody but a few of his cronies and some delusional tech bros and people who want us uppity women, liberals, democrats, and other races to know our place under their boot. They want us gone, and they’re succeeding all too well. I didn’t think we could be degraded this quickly.

        Only the earth itself can stop its apex predator from the full exercise of its hubris.

        Reply
    • Barton Paul Levenson says

      12 Aug 2025 at 8:49 AM

      V: my claim to lack of correlation was in reference to modern, not ancient, history. I assumed you knew that.

      BPL: On this board, it’s very much ancient history. It’s been pointed out to you time after time that the correlation is very strong for data going back to 1850 (CRU) or 1880 (NASA). You simply refuse to acknowledge it, or you redefine what “correlation” means.

      V: I was referring to SO2 emissions during the 40 years from 1940-1979, which, according to the mainstream view, masked the expected warming during that period. I assumed you were aware of that since I’ve posted on it more than once above.

      BPL: First of all, stop saying “1979.” According to tamino’s very careful change point analysis, the inflection point is 1975. Second of all, I showed statistically that aerosols are indeed negatively correlated to surface temperature, but as usual with you, it just goes in one ear and out the other. You simply refuse to acknowledge anything anybody says that disagrees with you.

      Reply
  45. Thessalonia says

    11 Aug 2025 at 11:58 PM

    Before Limits to Growth there was this
    https://archive.org/details/in.gov.ignca.5089/mode/2up
    The world ignored both.

    Reply
  46. Thessalonia says

    12 Aug 2025 at 12:10 AM

    Re-examining ‘Doomerism’: When Does Pessimism Become Scientific Caution?

    1. The ‘Doomer’ Label as Rhetorical Silencing

    – The term is often used to dismiss legitimate critiques of IPCC’s SSP energy-growth assumptions (e.g., Michaux 2021 on mineral shortages).

    – Contrast with Hansen et al. (2024): “Empirical data now outpaces CMIP6 ensemble projections for key feedback loops.”

    2. Neurodiversity and Systems Literacy

    – Linear institutional models struggle to integrate nonlinear climate responses (cf. Rockström’s tipping points).

    – Implication: Dismissing “doomer” concerns risks excluding autistic/ADHD researchers who excel at pattern-recognition in chaos.

    3. A Proposal for Inclusive Debate

    – Could the IPCC host a working group on cognitive diversity in climate modeling?

    – Example: Leverage agent-based modeling (vs. equilibrium economics) to capture abrupt change.

    Citations:
    – Hansen + Sato (2024): “Sophie’s Planet” (ch. 12 on institutional myopia).
    – Tverberg (2017): “Energy limits to complexity in economic systems.”

    PS I welcome corrections if any citations are misrepresented—particularly from Dr. Mann’s team.

    Reply
    • nigelj says

      12 Aug 2025 at 3:52 PM

      Thessalonia said : “1. The ‘Doomer’ Label as Rhetorical Silencing – The term is often used to dismiss legitimate critiques of IPCC’s SSP energy-growth assumptions (e.g., Michaux 2021 on mineral shortages).”

      Michaux key point is he observes that we most likely don’t’ have enough mines currently in operation to provide for anticipated resource demands to build a 100% renewables grid ( I strongly suspect we don’t have enough mines in operation to meet the needs of a future fossil fuels powered grid either). I see no reason to doubt Michaux basic conclusion. So in no way do I DISMISS his study.

      I label his observations DOOMY because :

      1) We can open more mines. We have discovered good quality deposits we know can be mined as required. Michaux says it takes a long time to open new mines. I would suggest if we have materials shortages those times will be shortened. The times often reflect regulatory requirements.

      2) Its likely discoveries will be made of more mineral deposits . Not certain but reasonably likely.

      3) There are vast quantities of minerals dissolved in sea water, and geothermal brines we know can be extracted although the economics do vary.

      4) There is potential sea bed mining and the resource is huge..

      5) Much more use could be made of recycling existing materials, thus minimising the need to open more mines.

      See the difference Thessalonia?

      Reply
    • Barton Paul Levenson says

      13 Aug 2025 at 8:49 AM

      Th: The ‘Doomer’ Label as Rhetorical Silencing

      BPL: Thanks for the tone trolling.

      Reply
  47. Karsten V. Johansen says

    12 Aug 2025 at 1:21 AM

    The by now already fast moving climatic and ecological collapse of mankind can’t be slowed down by academic smalltalking it as if it were a minor technical problem like the adjustment of the brakes of your car, where to put the TV in your living room etc. But that is – obviously inevitably – what socalled “modern” human beings automatically do, fx. here: https://m.youtube.com/watch?v=CVY2iJU4D6Y . It’s like listening to a K”I” robot. My conclusion: unfortunably homo sapiens, with its relentlessly growing exploration of fossil fuels, has arrived at the end point in it’s very short part of the history of life on earth. For many of the other lifeforms this maybe their only chance left.

    Reply
    • Susan Anderson says

      13 Aug 2025 at 9:20 AM

      Saw that yesterday. Peter Sinclair’s This is Not Cool (Thinc) blog is a useful summary of what’s going on in the world, including positive action:
      https://thinc.blog/

      Reply
  48. Thomas says

    12 Aug 2025 at 1:37 AM

    Evolution of long-term global drought during past 70 years based on estimated evaporation using the generalized complementary relationship — Journal of Hydrology, April 2025

    Principle Findings:
    Drought increased in 45% of the Earth’s land and was mainly driven by increased atmospheric evaporative demand.
    Most of Africa and South America, Mediterranean region, southeastern China, and Canada were hot spots of drought increase.
    Changes in vapor pressure deficit and wind speed dominated drought changes in 80% of the Earth’s land.

    With the intensification of global warming, meteorological drought is becoming increasingly frequent, leading to agricultural drought, hydrological drought, and socioeconomic drought as a result of the propagation through the water cycle (Kim et al., 2019).

    Unprecedented continental drying, shrinking freshwater availability, and increasing land contributions to sea level rise — Science Advances, July 25th 2025

    Changes in terrestrial water storage (TWS) are a critical indicator of freshwater availability. We use NASA GRACE/GRACE-FO data to show that the continents have undergone unprecedented TWS loss since 2002. Areas experiencing drying increased by twice the size of California annually, creating “mega-drying” regions across the Northern Hemisphere.

    While most of the world’s dry/wet areas continue to get drier/wetter, dry areas are now drying faster than wet areas are wetting.

    The researchers were surprised to find that the loss of water on the continents has grown so dramatically, that it has become one of the largest causes of global sea level rise. Moisture lost to evaporation and drought, plus runoff from pumped groundwater, now outpaces the melting of glaciers and the ice sheets of either Antarctica or Greenland as the largest contributor of water to the oceans.

    In the Central Valley, CA, the ground surface is nearly 30 vertical feet lower than it was in the first part of the 20th century.

    The study (Unprecedented continental drying, shrinking freshwater availability, and increasing land contributions to sea level rise) examines 22 years of observational data from NASA’s Gravity Recovery and Climate Experiment, or GRACE, satellites, which measure changes in the mass of the earth and have been applied to estimate its water content.

    Since 2002, the GRACE sensors have detected a rapid shift in water loss patterns around the planet. Around 2014, though, the pace of drying appears to have accelerated, the authors found, and is now growing by an area twice the size of California each year.

    Worldwide, 70% of fresh water is used for growing crops, with more of it coming from groundwater as droughts grow more extreme. Only a small amount of that water seeps back into aquifers.

    “The U.S. doesn’t have a national water strategy,” Famiglietti said, referring to a disjointed patchwork of state and court oversight. “We don’t even have a national water institution. We haven’t thought as a country about how we would even protect our own water resources for our own national interests, and we’re a mess.”

    8 Things to Know About New Research on Earth’s Rapid Drying and the Loss of Its Groundwater

    Much of the Earth is suffering a pandemic of “continental drying,” affecting the countries containing 75% of the world’s population, the new research shows.

    Mining of underground freshwater aquifers is driving much of the loss.

    Much of the water taken from aquifers ends up in the oceans, contributing to the rise of sea levels.

    Water From Land Has Become a Leading Driver of Sea Level Rise

    As droughts grow more extreme, farmers increasingly turn to groundwater.

    Drying regions of the planet are merging.

    Water pumped from aquifers is not easily replaced, if it can be at all.

    As continents dry and coastal areas flood, the risk for conflict and instability increases.

    The accelerated drying, combined with the flooding of coastal cities and food-producing lowlands, heralds “potentially staggering” and cascading risks for global order, the researchers warn. Their findings all point to the likelihood of widespread famine, the migration of large numbers of people seeking a more stable environment and the carry-on impact of geopolitical disorder.

    Various citations:
    Unprecedented continental drying, shrinking freshwater availability, and increasing land contributions to sea level rise July 2025
    https://www.science.org/doi/10.1126/sciadv.adx0298

    https://www.carbonbrief.org/global-soil-moisture-in-permanent-decline-due-to-climate-change/

    Continuous increase in evaporative demand shortened the growing season of European ecosystems in the last decade
    https://www.nature.com/articles/s43247-023-00890-7

    Evolution of long-term global drought during past 70 years based on estimated evaporation using the generalized complementary relationship April 2025
    https://www.sciencedirect.com/science/article/abs/pii/S0022169424019280

    Reply
    • Barry E Finch says

      12 Aug 2025 at 10:43 AM

      Thomas 12 Aug 2025 at 1:37 AM “Moisture lost to evaporation and drought, plus runoff from pumped groundwater, now outpaces the melting of glaciers and the ice sheets of either Antarctica or Greenland as the largest contributor of water to the oceans.”
      Appears to conflict with:
      Isabella
      Velicogna Chandanpurkar et al 25 Jul 2025
      243 273 Mountain Glaciers
      266 234 Greenland
      135 91 Antarctica
      n/a 81 Groundwater depletion (regionally highly variable, large gains and large losses).
      https://www.youtube.com/watch?v=nObqORopRNw 3:37 9:40
      But depending on what “now” means because “now” is meaningless for these scientific analyses. No information in it.

      Reply
      • Prietos Principles says

        12 Aug 2025 at 6:48 PM

        Barry E Finch says

        12 Aug 2025 at 10:43 AM
        Appears to conflict with: ?
        But depending on what “now” means ?

        Thomas quoted papers
        April 2025
        July 2025
        (Kim et al., 2019)

        Papers are always conflicting with other papers. They are like blog comments. Deal with it or give up, or ignore it like most people and most climate scientists and the IPCC do.

        Reply
        • Barton Paul Levenson says

          13 Aug 2025 at 8:52 AM

          PPr: Deal with it or give up, or ignore it like most people and most climate scientists and the IPCC do.

          BPL: Gosh darn those scientists! If only they’d listen to the Doomers.

          Reply
    • Victor says

      12 Aug 2025 at 11:04 PM

      From Nature, 2012

      “Little change in global drought over the past 60 years”

      https://www.nature.com/articles/nature11575

      From the EPA, 2023:

      “Figure 1. Average Drought Conditions in the Contiguous 48 States According to the Palmer Index, 1895–2023”

      https://www.epa.gov/system/files/styles/large/private/images/2024-05/drought_figure1_2024.png?itok=kn8bRGuQ

      Reply
  49. David says

    12 Aug 2025 at 1:29 PM

    “If we really want to have a shot at mitigating the worst effects of climate change, carbon removal needs to start scaling to the point where it can supplement large-scale emissions reductions.” — Adam Subhas, Woods Hole Oceanographic Institution
    .
    “Can We Alter the Ocean to Counter Climate Change Faster? This Experiment Aims to Find Out
    As corporate interest in ocean carbon removal grows, researchers from Woods Hole Oceanographic Institution are testing the safety and effectiveness of one such technique in the Gulf of Maine.”
    https://insideclimatenews.org/news/10082025/ocean-carbon-removal-climate-change/
    .
    And on the albedo modulation front, a pair of interesting comments, one by Russell Seitz on his own work and the other by Kevin McKinney, each linking to papers worth reading imo:

    https://www.realclimate.org/index.php/archives/2025/07/the-endangerment-of-the-endangerment-finding/#comment-837289

    https://www.realclimate.org/index.php/archives/2025/08/unforced-variations-aug-2025/#comment-837260
    .
    I’m far from bright enough to evaluate the trio of concepts outlined above. That’s not the point though. It’s easy for me to get discouraged by the combination of how big the climate change problem is already, how much worse it will grow, the societal impacts that will only grow with time, and the seemingly endless impediments slowing/blocking actions arising from humans being, well, human.

    Then I read about people who didn’t and don’t stop thinking and working at ideas that may contribute positively towards solutions. And that helps me remain hopeful even in the gathering darkness of what awaits us all because of prior choices made and imposed.

    Reply
  50. Pete bestyville says

    12 Aug 2025 at 1:46 PM

    Is it as yet accepted that the rate of CC had increased ?

    https://youtu.be/o-pZNRN4XAE

    Reply
    • Prietos Principles says

      12 Aug 2025 at 6:27 PM

      No. Not according to M Mann

      Mann13 (2023)
      Twitter denial of aerosol forcing decline post-2020; While he uses a 2019 Nature article as evidence

      “IPCC represents the consensus. Individual articles don’t. Until there’s a major assessment (NAS or IPCC) saying otherwise, the claim of a sharp decrease in global aerosol forcing past 4 years must be considered an extraordinary claim lacking evidence. I’m done w/ this now, ok?”

      https://nitter.poast.org/MichaelEMann/status/1673511877790388225#m

      Reply
      • Pete Best says

        13 Aug 2025 at 10:12 AM

        Yes Mann is a significant Climate Scientist but so is Stefan. I am not sure who else who else has weighed in on the debate but it does appear to be very quiet on this one considering the implications of a 50-100% increase in warming would mean (0.3-0.4C warming per decade) 1.9- 2C by 2050.

        Reply
    • Barry E Finch says

      12 Aug 2025 at 7:48 PM

      I don’t know about “climate change” and I don’t know whether it’s much well defined so’s it could be quantified (maybe someone round here knows). There’s no doubt whatsoever that the rate of GMST increase has been increasing for at least a decade or so but It’s the amount of increase and details of dates and of why(s) (that is, how much fractional contribution comes from each cause) that’s apparently a bit debatable. It would likely violate some thermodynamic Law if the rate of GMST increase didn’t increase because humans are relentlessly increasing the global heater and the general Rule of Heaters is “The bigger the heater the faster it heats”. That rule could be broken for Earth ecosphere as far as I can see only by a long-term (multi-decadal+) rate increase in ocean bringing up its old cold water or by an increase in human-made “global dimming” atmospheric aerosols because those are the 2 other big things than GHGs, but the scientists are clear that both of those have been decreasing not increasing so there’s nothing that would prevent the increasing global heater from warming the surface-troposphere at an increasing rate. But what IS that rate as a trend when the trend is drawn at 2045 CE and it’s seen what the a trend was at 2025 CE?”

      Reply
      • Barton Paul Levenson says

        13 Aug 2025 at 10:49 AM

        BEF: There’s no doubt whatsoever that the rate of GMST increase has been increasing for at least a decade or so

        BPL: On average, for 17 decades.

        BEF: but It’s the amount of increase and details of dates and of why(s) (that is, how much fractional contribution comes from each cause) that’s apparently a bit debatable

        BPL: Try here:

        https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt

        Reply
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