Our new climate sensitivity paper has been published

September 29th, 2023 by Roy W. Spencer, Ph. D.

If we assume ALL *observed* warming of the deep oceans and land since 1970 has been due to humans, we get an effective climate sensitivity to a doubling of atmospheric CO2 of around 1.9 deg. C. This is considerably lower than the official *theoretical* model-based IPCC range of 2.5 to 4.0 deg. C. Here’s the Phys.org news blurb from this morning.


118 Responses to “Our new climate sensitivity paper has been published”

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  1. Tim Folkerts says:

    Congratulations. A well-deserved accomplishment

  2. Ireneusz Palmowski says:

    Im afraid that soon waves of cold air will start coming down from the north.
    https://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_HGT_ANOM_ALL_NH_2023.png

  3. Entropic man says:

    Nice one.

  4. Norman says:

    You base your 1.9 C on evidence and accumulated data. Will the science community consider this paper and look deeper at the much higher figures given by others?

  5. Nate says:

    Nice work.

    Do you consider any effects of aerosols to have reduced the warming up to the present?

    • Dave Burton says:

      It’s just the opposite. Aerosol & particulate air pollution abatement is responsible for some of the recent warming.

      Paper:
      https://doi.org/10.5194/acp-2022-295

      Article about the paper:
      https://phys.org/news/2022-09-air-quality-global-decades.html

      If a higher percentage of observed warming is due to aerosol & particulate air pollution abatement, that means a lower percentage of observed warming is due to GHGs. This is yet more evidence that climate sensitivity to CO2 is generally overestimated.

      Additionally, the widely hyped recent spike in air and ocean temperatures is a predictable consequence of the new IMO 2020 international shipping regulations, which curtailed sulfate aerosol emissions from ships.

      The new regulations resulted in “an estimated 46% decrease in ship-emitted aerosols,” and (because ships are a major contributor), a 10% decrease in total global sulphur dioxide (SO2) emissions.

      I’m going to limit the number of links in this comment to two, to try to avoid the moderation queue, but if you want to learn more about it you can search for articles with titles like these:

      ● Global reduction in ship-tracks from sulfur regulations for shipping fuel

      ● NASA Study Finds Evidence That Fuel Regulation Reduced Air Pollution from Shipping

      ● Low-sulfur shipping rules are affecting global warming

      It’s not a problem, it’s good news, because it is evidence that the pollution controls are working.

      It has nothing to do with carbon emissions, and it doesn’t mean people need to scrap their SUVs or freeze in the dark to “save the planet.”

      • Nate says:

        I agree with you on the ship aerosols. Their removal has allowed GW to accelerate.

        Consider that Roy’s analysis is of the warming during the period 1970-present, and assigning that to GHG forcing.

        But during that period aerosols were a cooling influence, and it was not considered.

        With their removal, we are able to see that the GW is accelerating. We have yet to see how much additional warming that will yield.

    • Nate says:

      “Its just the opposite. ”

      Not the opposite. Abatement means removal. Removal of a an effect that ‘reduced warming up to the present’ as I stated.

    • Nate says:

      “If a higher percentage of observed warming is due to aerosol & particulate air pollution abatement, that means a lower percentage of observed warming is due to GHGs. ”

      With aerosols present the effect of GHG is partly cancelled. With abatement of aerosols, the GHG warming is no longer cancelled and we see its full impact.

      • Dave Burton says:

        The Spencer/Christy study used data since 1970. In North American and Western Europe, the 1960s and 1970s were the peak of aerosol & particulate air pollution. But in 1967 the first scrubber was installed in a power plant, and in 1971 the U.S. “New Source Performance Standards” first imposed limits on SO2 emissions from new coal power plants.

        Since then air pollution has been drastically curtailed, though it has worsened in some other places.

        In the 1970s the twin scares w/r/t fossil fuels (besides running out!) were global cooling (loosely, “a new ice age”), and acid rain. Sulfur aerosol emissions were thought to be the chief culprit w/r/t acid rain, and also a major contributor, along with particulates, to global cooling.

        Here’s Newsweek reporting the grim outlook in 1975:

        https://sealevel.info/newsweek_old.htm

        Ground-level air pollution had long been recognized as a significant public health problem. But prior to the “new ice age” (global cooling) and “acid rain” scares, the standard remedy for protecting people from ground level air pollution caused by coal-fired electrical power plants was simply to build very tall smokestacks.

        That was effective for addressing the public health problems (except when thermal inversions brought the smoke back down to ground level, most infamously in Los Angeles). But it had side-effects, such as aerosols which cause cooling.

        So, in the mnid-1970s building tall smokestacks to abate ground-level air pollution went out of fashion in the western hemisphere. The tallest chimney ever built in the United States was apparently at Homer City Generating Station, in Homer City, PA (≈¼ mile tall), in 1977; here’s a photo of it:

        https://sealevel.info/homer-city_jon-dawson-800.jpg

        The global cooling scare of the 1970s, and the acid rain scare of the late 1970s and 1980s, put an end to those giant smokestacks. Power plants still have chimneys, but building taller and taller chimneys hasn’t been considered a primary remedy for air pollution in nearly half a century.

        Power plants in first world countries are very, very clean these days. There are no longer any operating coal-fired power plants in the USA without scrubbers, and there haven’t been for many years.

      • Nate says:

        “though it has worsened in some other places.”

        I agree, in Asia. So it has been ongoing.

      • Nate says:

        BTW. It is a myth that there was a global cooling scare in the 70s.

  6. Swenson says:

    Dr Spencer,

    If you assume that all deep ocean warming is due to human activities, you would be wrong.

    The oceans are the temperature they are because they sit in basins of rock which are hotter than the oceans. Any water heated by the Sun sits on the surface, and radiates the heat of the day to outer space at night. Slowly or quickly makes no difference ultimately.

    The fact that the oceans are as cold as they are is proof that the “heating” effect of CO2 is precisely zero. The oceans are no longer boiling, as was the case when the first liquid water appeared, and CO2 has been present in the atmosphere in far greater concentrations in the past.

    As man made “ocean warming” appears to be negligible, and oceans comprise some 70% of the planet’s surface, your supposed “climate sensitivity” might well reduce to zero, or slightly less.

    There is still precisely no experimental evidence to show that inserting CO2 (or any other gas) between a heat source and a thermometer, makes the thermometer hotter. Therefore, no experimental support for any positive “climate sensitivity” at all.

    Swenson:
    So, you don’t believe the geophysics experts who say the average geothermal heat flux is only a tiny fraction of 1 W per sq. meter, while the global average solar input is ~240?? They have measurements of the temperature profile with depth from boreholes, and that combined with the thermal conductivity of rock, leads to tiny heat flux values. The few deep-sea volcanoes and “smokers” cover such a tiny fraction of the ocean bottom that they make almost no difference, just as they make no difference to atmospheric temperatures. Water temperature measurements near the ocean bottom are exceedingly cold everywhere, only 1 – 3 deg. C, because that bottom water was chilled at the surface at high latitudes, where it became more dense and sank to the bottom.
    Yet you claim the cold deep oceans are heated geothermally? Oh, my.
    -Roy

    • gbaikie says:

      “If we assume ALL *observed* warming of the deep oceans and land since 1970 has been due to humans, we get an effective climate sensitivity to a doubling of atmospheric CO2 of around 1.9 deg. C.”

      So, if we ignore any natural warming {or natural cooling}.
      And what seems to me, according to this, we have already added enough CO2 {assuming it wasn’t naturally added or would not have been subtracted, naturally} to about 1/2 of the 1.9 C.
      And CO2 rises higher 500 ppm {500 to 600 ppm} then we get the other half somewhere in decades after rising higher than 500 ppm as measured from a high elevation volcano in the pacific ocean.

      And at moment average global surface air temperature is about 15 C.
      And it seems if get such warming we get more warming of land surface air temperature, which is around 10 C and less warming ocean surface temperature which don’t know, but is somewhere around 17 C.
      And of the land surface, more warming of Land surface in closer to pole.
      So, Canada with average temperature surface air temperature of about -3 C so could warm up to about -2 C.
      But Canada fast population rate, could result in more urban heat island effects which in terms people living in urban areas, one could a higher air temperature in towns/cities from UHI effects.
      But bottom line is the animals which are freezing to death will have milder freezing to death.

    • Nate says:

      This illustrates nicely the stark difference between a science denier (Swenson), who just declares stuff, and a scientific skeptic (Roy) who supports his claims with science.

      • Swenson says:

        What a load of tosh, Nate!

        As Richard Feynman agreed “It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong.”

        Anybody who claims “science says . . .”, or something similar, does not understand what science is.

        You, for example.

      • Nate says:

        And he keeps on just declaring stuff anyway..

      • Stephen P Anderson says:

        Nate,
        Not really. Dr. Spencer is showing the deniers are on the left. Swenson is saying things like if the actual evidence shows that CO2 follows temperature, then it kind of puts a big hole in the whole GHE thing.

      • Willard says:

        A model that minimizes sensitivity but still accepts that CO2 warms the atmosphere is far from showing that Sky Dragon cranks such as you are correct, Troglodyte.

      • Swenson says:

        A model which does not reflect reality is not fit for purpose.

        SkyDragons believe that CO2 has magic powers, and will result in us all being seared by its fiery breath. Here’s one example “Unless we take action on climate change, future generations will be roasted, toasted, fried and grilled.” – Head of the IMF.

        Really? She believes the climate can be prevented from changing?

        Pardon me while I laugh at SkyDragon fantasies!

        You can’t even describe this GHE which is going to result in us all being “roasted, toasted, fried and grilled”!

        Go on with with your weird SkyDragon cultist beliefs. Do you bow down to pictures of Gavin Schmidt and Michael Mann each morning and evening? More often?

        [chortling]

      • Nate says:

        “SkyDragons believe that CO2 has magic powers”

        Swenson is calling Roy Spencer a SkyDragon, whatever that is?

        And declaring that he (Roy) believes in magic!

        Meanwhile Swenson just cannot seem to grasp that 240 W/m^2 input from the sun is much much MUCH larger than the 0.1 W/m^2 from geothermal heat.

        Yet he insist that this geothermal energy must be what’s heating the ocean!

        It appears that he is the believer in magic.

      • Nate says:

        Stephen missed Roy’s points, in his post, his paper, and his response to science denying Swenson.

      • Swenson says:

        What do mean “science denying”, you silly man?

        Like Richard Feynman, perhaps, who agreed “It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong.”

        You obviously disagree, and you are free to express your opinion, no matter how misguided.

        I support absolute freedom of speech. Facts are facts, whether you deny them or not.

        That’s reality.

      • Nate says:

        “What do mean science denying”

        Pretty obvious to everyone else but you. Roy did science to find evidence to support his claims. You declared it wrong based on no evidence at all.

    • Swenson says:

      Dr Spencer,

      What has the heat flux from the interior to do with sunlight? The influence of the Sun is unnoticeable beyond 30 m or so at maximum, in the crust, maybe 200 m in the ocean.

      Belief has nothing to do with fact, and the fact is that nobody has ever managed to make a thermometer hotter by increasing the amount of CO2 between the thermometer and a heat source.

      As to the bottom waters being cold because water cools at higher latitudes, sinks, and decides to flow around the surface of a sphere for no good reason, that’s just silly. Water doesn’t flow all by itself – it sinks under the influence of gravity – towards the center of the Earth, whether at the poles, or the equator. The densest water is found at the bottom of the water column.

      I guess not many people realise, as NOAA says “The massive mid-ocean ridge system is a continuous range of underwater volcanoes that wraps around the globe like seams on a baseball, stretching nearly 65,000 kilometers (40,390 miles). The majority of the system is underwater, with an average water depth to the top of the ridge of 2,500 meters (8,200 feet).”

      Molten magma meets the deep waters continuously. Just some fairly spectacular minor interior heat reaching the ocean – in addition to a totally unknown amount from hydrothermal vents. In any event, deep ocean currents are due to convection, plain and simple. Chaotic flow, the subject of much of Edward Lorenz’s work – applicable to fluids like water, as well as the atmosphere.

      When you write “Yet you claim the cold deep oceans are heated geothermally? Oh, my.”, your appeal to your own authority falls flat. The deep oceans are indeed heated geothermally, sitting on the surface of a ball of rock which is more than 99% hot enough to glow!

      I suppose you might not believe that Antarctic ice several kilometers thick actually gets warmer as you approach the bedrock, but it does. Here’s a snippet – “For a thick ice sheet such as is the case at South Pole, the temperature distribution near the ice-bedrock interface depends mainly on the geothermal heat flux, . . . ”

      Of course, the thicker the ice or the deeper the ocean, the thinner the crust and the closer the glowing mantle.

      Do you really think the deep cold water at the equator is due to water cooling at the poles, and migrating north and south due to some celestial force overcoming the force of gravity? Oh my!

      Maybe you can put me firmly in my place by producing some facts, rather than beliefs and feelings. I doubt it.

      • Ken says:

        Swenson, Your Homework is to study thermohaline circulation as it pertains to ocean currents.

        The homework will reveal a lots of facts that will overturn your entire system of beliefs and feelings. Good luck.

      • Swenson says:

        Ken,

        My beliefs and feelings have nothing to do with facts.

        Your Homework is to study physics.

        The Wikipedia article on thermohaline circulation is mostly erroneous – based on wishful thinking. However, where it says “The dense water masses formed by these processes flow downhill at the bottom of the ocean, like a stream within the surrounding less dense fluid, and fill up the basins of the polar seas.”, it’s right. However, once a basin is filled with the densest water, it remains “filled”. The water sits there – going nowhere, up, down, or sideways!

        I’m sure you will attempt to explain how this densest water magically “upwells” through overlaying warmer less dense water, or goes on vacation to the equator, but you will fail.

        About as silly as Trenberth and Co. asserting that water warmed on the surface can magically descend into the depths (remaining warmer than the water surrounding it) where it cannot be detected. Even Trenberth said that was a “travesty” – of physical law, that is. Yup. He was right about that, at least.

      • Ken says:

        “However, once a basin is filled with the densest water, it remains filled. The water sits there going nowhere, up, down, or sideways!”

        Fill your bathtub. Leave the taps running. See what happens. For some unknown reason the water doesn’t just sit there; it overflows the tub and keeps spreading.

      • Swenson says:

        Ken,

        Don’t be silly.

        If you want to use silly and irrelevant analogies, fine. If you want to ignore reality, fine.

        If you really believe that the water overflowing your bathtub at the North Pole somehow winds up at just above freezing at the bottom of the Mariana Trench, having traversed the ups and downs of the ocean floor topography, travelled across a series of mid ocean ridges exuding molten magma, and then plunges to the sea floor, displacing colder denser water, due to the awesome power of your will, you might be quite mad.

        You are free to believe anything you want, no matter how unrealistic it may be.

      • Nate says:

        “My beliefs and feelings have nothing to do with facts.”

        Whoops! Accidental truth telling.

      • Nate says:

        “As to the bottom waters being cold because water cools at higher latitudes, sinks, and decides to flow around the surface of a sphere for no good reason, thats just silly. ”

        Swenson continues his science denying ways, declares more stuff that he cannot support with evidence.

      • Swenson says:

        Nate,

        Fact, unless you can provide physical reason for water flowing around a sphere suspended in space. About as silly as dropping a marble at the pole, and expecting it to roll to the equator.

        Give it a try.

        You really are a gullible SkyDragon cultists, aren’t you?

      • Nate says:

        “Fact, unless you can provide physical reason for water flowing around a sphere suspended in space.”

        Your ignorance-based theory that it cannot happen is falsified by the many observations of it happening.

        Feynman sez your theory is BS!

      • Swenson says:

        Nate,

        Water doesn’t flow from the poles to the equator, nor vice versa, without some force being applied.

        Deep ocean currents are due to convection, pure and simple. Keep banging on without providing any supporting information.

        Someone might believe you – another SkyDragon cultist, perhaps?

      • Nate says:

        “Water doesnt flow from the poles to the equator, nor vice versa, without some force being applied.”

        You don’t get that gravity applies a force on denser water?

        Feynman says you need to stop associating his name with such stoopid ideas.

      • Dave Burton says:

        If Swenson doesn’t believe in the AMOC etc. (the slow deep ocean currents which return very cold water from high latitudes to the tropics), then presumably either:

        1. He’s never heard of the Gulf Stream, which carries so much heat from the tropics to the north Atlantic that it makes northern Europe habitable. Or else,

        2. He doesn’t realize that since the Gulf Stream’s warm water flows north, something must also be carrying water back south again. After all, that Gulf Stream water can’t just pile up in the North Atlantic.
         

        Here’s a question: Would you rather live at the latitude of Hudson Bay (known for its polar bears), or the latitude of Scotland (known for its sheep and cattle)?

        {Please think about your answer before reading on.}
        .
        .
        .

        It’s a trick question, because brutally frigid Hudson Bay and merely chilly Scotland are at about the same latitude! The Gulf Stream is the only thing keeping places like Scotland habitable.

        https://sealevel.info/Scotland_centered_on_57.5N_latitude_same_as_Hudson_Bay.png

        Were it not for the Gulf Stream & AMOC, Scotland would be a lot more like Hudson Bay. But the circulation is highly asymmetrical. The transit time for warm surface water water moving north from the Gulf of Mexico toward Europe is measured in mere months. But the deep return currents take about a millennia to return cold water to the tropics.

        https://www.youtube.com/watch?v=2RD3I69k71Y

    • Damian says:

      I think many people on this site are missing the bigger picture. Increasing CO2 in the air normally shouldn’t be a problem, as increasing CO2 increased vegetation which then reduces the temperature.

      https://www.britannica.com/video/179436/Overview-impact-Sahara-discussion-desert-climate-change

      The problem however is that as humans we are cutting down trees faster than they are growing. Especially cutting down old growth forests.

      https://ourworldindata.org/deforestation

      Its seems like we are cutting down trees faster than they can grow. Especially with the whole green bags things which use paper at our local super market which ends up cutting trees down so we don’t use plastic.

      The Earth is quite resilient but we are doing our absolute best to screw over natural heat sinks.

  7. E. Schaffer says:

    “If we assume ALL *observed* warming of the deep oceans and land since 1970 has been due to humans, we get an effective climate sensitivity to a doubling of atmospheric CO2 of around 1.9 deg. C.”

    I feel a lot of pain over this sentence. We simply have to consider aviation induced cirrus clouds! It IS anthropogenic, but it is NOT CO2, and it is heating the Earth more like anything else.

    https://greenhousedefect.com/contrails-a-forcing-to-be-reckoned-with

    E. Scaffer:
    Best estimates of regional to global radiative forcing from contrails are generally below 0.1 W m-2, so negligible. This review paper (link below) discusses the complexities of the subject, and despite the paper’s initial claim that contrails “contribute to anthropogenic climate change”, the numbers in the paper, based upon decades of research by many people, show that such phrasing is an exaggeration.
    https://www.nature.com/articles/s41467-018-04068-0
    -Roy

  8. Ireneusz Palmowski says:

    How the “anomalous” amount of heat in the tropical Pacific at a depth of 150 m has changed since June 2023.
    http://www.bom.gov.au/archive/oceanography/ocean_anals/IDYOC006/IDYOC006.202309.gif

  9. Ireneusz Palmowski says:

    The surface temperature of the Gulf of Alaska is dropping rapidly, promising early snowfall in the Rocky Mountains.
    https://www.tropicaltidbits.com/analysis/ocean/cdas-sflux_ssta_global_1.png

  10. Anon for a reason says:

    Congratulations on getting your good quality research published.

    I do wonder how it will be received by the rest of the AGW industry.

    -Not well, I suspect. Or, it will simply be ignored. -Roy

    • Nate says:

      One should be aware that there are already many papers analyzing climate sensitivity.

      Roy’s is not the first and won’t be the last, and its results are not very different or surprising.

    • Clint R says:

      Dr. Spencer says: Not well, I suspect. Or, it will simply be ignored.

      Exactly. The cult does not want facts. They reject reality.

      I don’t know how this nonsense will end. Even if we had another ice age, I suspect the cult would claim it was due to mankind, somehow!

  11. Nick Stokes says:

    I wondered why this was considerd novel when similar modeling goes back to Manabe and Wetherald 1967, and most recently in the unpublished paper of Happer and Wijngaarden. As the latter show in their Table 5, all the results are consistent, with an ECS for fixed RH of about 2.2. This result is not so different.

    But I was puzzled about the mention of scenarios, and realised that, instead of calculating the radiative forcing, this paper used GCM diagnoses. That might bother some here, but not me. What does bother me is that the latter years of the period wre not observations in any sense, but predictions dependent on assumed scenario.

    – There are only a few years at the end of the period that were scenario predictions of emissions rather than observations, but all of those are nearly the same, because they were so close to the observational period. It’s a non-issue regarding the results.
    -Roy

    • Nick Stokes says:

      Its a non-issue regarding the results.

      But one scenario gave 1.86 C, another gave 2.49 C per doubling. That doesn’t seem like a non-issue.

      -Because over 50 years the accumulated forcing from the 2 scenarios are sufficiently different, but the last few years at the end make little difference.
      -Roy

      • frankclimate says:

        Indeed the (IMO big) difference between the SSP2-4.5 and RCP6 scenario should be discussed. The only issue I can imagine is a different ERF aerosol in the datasets of the scenarios. Is this true?

        -Yes, I suspect the major reason for the difference in forcing scenarios is aerosols.
        -Roy

      • frankclimate says:

        Hi Roy, there is an updated ERF dataset ( up to 2022) from this paper: https://essd.copernicus.org/preprints/essd-2023-166/essd-2023-166.pdf . So you could use this data avoiding the need of any scenario with different EffCS values also for the latest datapoints.
        best Frank

  12. MikeM says:

    I like that you recognize conservation of energy should be included. The old hockey stick curve always seemed like we would go into thermal runaway.

  13. gbaikie says:

    Ok, failed twice.
    You got the listen to Dennis

    • gbaikie says:

      Prager

      • gbaikie says:

        Talking to Kennedy, Jr

      • gbaikie says:

        Robert F. Kennedy, Jr. also prompted about climate change.

        Says could be biggest humans have experience.
        I would say the change on Sahara desert has been biggest.
        I think human can change the Sahara desert and/or “climate change” could change it.
        But it’s sort of what Californians have done in terms of southern
        California but on a much larger scale. And I don’t see as problem.

  14. Tim S says:

    Congratulations Dr. Spencer on getting this completed and published.

    The next topic I would like to see confirmed or refuted is the notion that unusual rain events leading to flooding are caused by increasing CO2, and whether or not that can be considered “climate change”.

    It is well known that instability in the atmosphere makes thunderstorms possible. The claim in the media is that a hotter atmosphere can hold more water vapor. It seems to me that the opposite claim would be more important, that increased instability caused by a cooler upper atmosphere, due to increasing CO2, would be a more likely explanation of increased rain intensity.

    So the question is, are these rain and flooding events, that are covered so heavily by the media, statistically significant on long term trends, and if so, what is the cause?

  15. Entropic man says:

    “The next topic I would like to see confirmed or refuted is the notion that unusual rain events leading to flooding are caused by increasing CO2, and whether or not that can be considered climate change. ”

    They are caused by increasing temperature.

    To what extent the increasing temperatures are due to increasing temperature is a separate issue, which relates to Dr Spencer’s paper.

    Incidentally, the link between increasing atmospheric temperature and increasing absolute humidity is not a claim by the media. It is standard physics.

    • Entropic man says:

      Curses. Make that

      “To what extent the increasing temperatures are due to increasing CO2 is a separate issue, which relates to Dr Spencers paper. “

    • Tim S says:

      An increase in dew point of 1 deg. C is worth about 0.1% increase in absolute humidity (1 part per thousand). What is your next claim?

      • Entropic man says:

        Observe

        https://en.m.wikipedia.org/wiki/Dew_point#/media/File%3ADewpoint.jpg

        Over the range from 0.C to 32C the saturation fraction rises from 0.7 percent to 3.1 percent.

        That is an increase of 3.1-07 = 2.4 percent or 2.4/32 = 0.07% per degree.

        As a percentage of the OC value that is an increase of

        3.1/0.7*100 = 442% or 442/32 = 13.8% per degree.

        We agree, at least approximately, but are expressing the change in different ways.

      • Tim S says:

        You are missing the point entirely. If you just like to argue, please continue without me. Absolute humidity is not a driving force. Do you understand the dynamics of thunderstorms?

        Thunderstorm development requires several things to initiate and then sustain vertical development. The primary driving force is instability to allow hot air at the surface to rise. That initial movement is increased by the near-adiabatic condensation of water vapor which adds temperature and buoyancy. Latent heat is exchanged for sensible heat raising the temperature and buoyancy. The process accelerates if all of the necessary conditions are met.

        Explain how an increase of 0.1% in humidity can cause a dramatic increase in rainfall. I can easily explain how increased instability increases the extent of the rainfall.

      • Entropic man says:

        A typical thunderstorm contains about 500 million kilograms of water vapour.

        Consider how increasing the starting conditions by 1C changes that.A worked example.

        At 20C each kilogram of saturated converting has a saturation fraction of 2% and therefore contains 20g of water vapour. At 21C that increases to 2.1% and 21g of water.

        Assuming that the same mass of air convects into each thunderstorm, a rise to 21C in surface temperature increases the amount of water vapour entering the thunderstorm by 1g per kilogram of air or 5% of the 20C value.

        The water vapour mass of the thunderstorm increases by 5%. When it precipitated that increases rainfall by 5%.

        500 million kg of rainfall from the thunderstorm becomes 525 million kg.

      • Nate says:

        “Explain how an increase of 0.1% in humidity”

        FALSE premise.

        “about 7%
        For every degree Celsius that Earth’s atmospheric temperature rises, the amount of water vapor in the atmosphere can increase by about 7%, according to the laws of thermodynamics.”

        https://climate.nasa.gov/explore/ask-nasa-climate/3143/steamy-relationships-how-atmospheric-water-vapor-amplifies-earths-greenhouse-effect/#:~:text=For%20every%20degree%20Celsius%20that,to%20the%20laws%20of%20thermodynamics.

        OTOH, with increasing T, we can naively expect increasing dynamics.

      • Tim S says:

        Nate, stop and think. 7% humidity is so high that none of my charts even show that. A dew point of 33C (91F) is 5.3 % absolute humidity (volume percent). This is my original quote and it is a reasonable estimate:

        “An increase in dew point of 1 deg. C is worth about 0.1% increase in absolute humidity (1 part per thousand). What is your next claim?”

        In the follow up, I left out the word “absolute” and you reacted to that quote. Let’s do the math lesson. The increase is 0.1%. If the basis is 1%, then the RATE of increase in the absolute increase is actually 10%. A different basis gives a different absolute increase and a different rate as well.

        All of this is speculation. Sadly, NASA has become pure hype. From your link:

        “Water vapor is Earths most abundant greenhouse gas. Its responsible for about half of Earths greenhouse effect”.

        Do you think it is only half?

        Have fun.

      • Entropic man says:

        TimS

        Water vapor is Earths most abundant greenhouse gas. Its responsible for about half of Earths greenhouse effect.

        Do you think it is only half? ”

        Roy’s recent paper tells you so. His conclusion is that climate sensitivity is 1.86+/-0.34, ie between 1.42 and 2.2.

        That tells us that half of the warming is due to the direct effect of the CO2 and the other half is due to indirect feedback effects. The largest indirect effect is the increase in water vapour and the water vapour greenhouse effect.

        It is reasonable to say that half of the observed warming is due to the changing CO2 greenhouse effect and the other half to the changing water vapour greenhouse effect.

        Digging a little deeper we can say that the increase in CO2 since 1880 has produced 0.6C of warming. This has increased the amount of water vapour in the atmosphere, and it’s increased greenhouse effect has caused another 0.6C of warming. The total surface warming is 1.2C as any of the surface datasets will tell you.

      • Entropic man says:

        TimS

        “7% humidity is so high that none of my charts even show that. ”

        Neither Nate or I are saying that the absolute humidity is 7%.

        We are saying that the water content of a unit volume of air at 15C is 107% of the water content at 14C.

      • Nate says:

        I think the point is it is a 7% increase in the amount of water in the cycle of evaporation and precipitation. A 7% increase in the latent heat available to drive weather. Sounds significant to me.

      • Swenson says:

        Nate,

        And yet, the less water in the atmosphere, the hotter the surface gets.

        And, of course, the coldest surface occurs where the atmosphere is driest, as well.

        The Moon is an example of things taken to extremes – its surface gets far hotter and far colder than the Earth’s. No atmosphere at all!

        Simple radiative physics. Possibly too mysterious for simple people like you.

      • Tim S says:

        A lot of people like to argue instead of thinking. The flood events that are making the news can be attributed to one of two things. They could be naturally occurring statistical anomalies, or they could be due to some type of change in the driving forces involved in thunderstorms.

        In order to rule out random chance, there has to be some kind of mechanism that increases the dynamics. Increased atmospheric instability caused by an excessively cold upper atmosphere is one possible mechanism. It could be blamed on increasing CO2, but that completely destroys the narrative that the whole atmosphere is heating up.

        A 7% increase in rainfall potential is not going to explain rainfall events that are sometimes an order of magnitude greater than the typical event for that location. 7% does not represent a substantial change in the system. In my original statement, a 1 part per thousand increase in the number of water molecules seems rather insignificant.

        To be fair, an increase in dew point from 20C to 21C is about a 7.3% increase in absolute humidity (0.16% increase in atmospheric volume), but an almost 6% increase in the enthalpy of the air at constant temperature. That is still only a very marginal increase.

      • Entropic man says:

        TimS

        One thing you haven’t mentioned is a change in the behaviour of storms. They are increasingly likely to become slow moving. Rather than moving on when they strike land, they stop a d dump much more rain on one area. Storm Danial in the Mediterranean this Summer did it twice. It stalled over Greece and flooded Thessaly, then regenerated over the Mediterranean and stalled over Libya.

        A number of recent US hurricanes have behaved in a similar manner.

      • Nate says:

        “It could be blamed on increasing CO2, but that completely destroys the narrative that the whole atmosphere is heating up.”

        Where do you get that narrative from? Certainly not from climate science!

      • Nate says:

        ” In my original statement, a 1 part per thousand increase in the number of water molecules seems rather insignificant.”

        Which is obviously not a useful way to look at it, since it tells you nothing about the relative change.

      • Nate says:

        Have to remember that the system involves nonlinear dynamics, and thus small changes in available energy can have large effects.

        1 C is significant warming in the tropical ocean because deep convection is strongly nonlinear in ocean temperature. And this is a driver of the global general circulation.

        For example El Nino increases equatorial ocean temps by 1 or 2 C, and causes world-wide changes in weather patterns.

      • Dixon says:

        FFS! The main reason floods are increasing is because humans like to build a load of impermeable things on floodplains.

        Sure, heavier thunderstorms could be causing more rain, but you don’t need more rain if the water can’t drain away like it used to.

        Plus we don’t manage waterways as we did 200 years ago (sometimes that’s a good thing).

        The German Floods in 2021 were terrible. But they were tiny compared to the flood of 1342:
        https://en.wikipedia.org/wiki/St._Mary_Magdalene%27s_flood

        Climate change is such a useful patsy that plenty of shrewd people will use it for their own ends. Thank goodness for people like Roy who persistently and thoughtfully consider what ‘truth’ is in spite of considerable personal detriment.

      • Tim S says:

        “‘It could be blamed on increasing CO2, but that completely destroys the narrative that the whole atmosphere is heating up.’

        Where do you get that narrative from? Certainly not from climate science!”

        Nate, you should read your own link. Where does it mention instability?

        https://climate.nasa.gov/explore/ask-nasa-climate/3143/steamy-relationships-how-atmospheric-water-vapor-amplifies-earths-greenhouse-effect/#:~:text=For%20every%20degree%20Celsius%20that,to%20the%20laws%20of%20thermodynamics

        This is a very embarrassing paragraph coming from people who are supposed to do science instead of propaganda. Do you endorse this?

        “It works like this: As greenhouse gases like carbon dioxide and methane increase, Earths temperature rises in response. This increases evaporation from both water and land areas. Because warmer air holds more moisture, its concentration of water vapor increases. Specifically, this happens because water vapor does not condense and precipitate out of the atmosphere as easily at higher temperatures. The water vapor then absorbs heat radiated from Earth and prevents it from escaping out to space. This further warms the atmosphere, resulting in even more water vapor in the atmosphere. This is what scientists call a “positive feedback loop.” Scientists estimate this effect more than doubles the warming that would happen due to increasing carbon dioxide alone”

      • Nate says:

        “This is a very embarrassing paragraph”

        You keep on asserting thinks like this without the slightest explanation of what, specifically, bothers you.

      • Nate says:

        And did you answer the question?

        “‘It could be blamed on increasing CO2, but that completely destroys the narrative that the whole atmosphere is heating up.’

        Where do you get that narrative from? Certainly not from climate science!”

    • Swenson says:

      The link between increasing atmospheric temperature and increasing absolute humidity seems a bit tenuous.

      The hottest places on Earth are characterized by a lack of absolute humidity – Death Valley, Lut desert and so on.

      As are the coldest, on the Antarctic continent.

      And, of course, CO2 concentrations do not result in higher temperatures. Removing CO2 from air makes no difference to the temperature, nor does replacing the air with 100% CO2.

      Standard physics.

      • Nate says:

        “The hottest places on Earth” ever ready with new red herrings..

      • Swenson says:

        As far as I know, both Death Valley and the Lut desert are also hosted for their lack of herrings – red or otherwise.

        Not enough water.

        Are you trying to say something, but unsure what it is that you are trying to say?

        Colour me unsurprised.

      • Dixon says:

        I want to know why most people seem happy to assume geothermal fluxes are constant? Nothing about earth processes seems to be steady state to me.

        I’d stake money there would have been some warmer ocean temps in the vicinity of Tonga almost two years ago. The amount of energy released from that point source makes me think we need pretty good measurements of heat flux from crust to oceans.

        -3C oceans are not cold. There’s 270 K left and its almost always hotter at 5000m below sea level than at 5000m above it, but we do like to worship the sun.

        This recent extreme heat is making a mockery of ‘consensus’ climate science and no one is really calling it out! It’s like no one needs plausible mechanisms now, it’s just ‘extreme weather’.

        We haven’t even fully mapped the sea floor depth in Antarctica, let alone understood the heat flux from it.

        “However, some of the recent drilling initiatives indicate a GHF of more than 115 mW/m2, far exceeding the GHF normally measured over the continental crust (Risk and Hochstein, 1974; Morin et al., 2010; Fisher et al., 2015). Such a high GHF, especially if valid on a regional scale, indicates a remarkably hot subsurface and would clearly have an effect on ice sheet dynamics.”

        https://www.frontiersin.org/articles/10.3389/feart.2020.00105/full

      • Swenson says:

        Dixon,

        The glowing interior of the Earth seems to be in constant motion. Crustal hotspots are measurable, and their tracks seem unpredictable and chaotic in nature. One hypothesis is that hotspots result from magma plumes, which begs the question – what heat gradients drive the convection within the fluid interior of the Earth?

        Why do the magnetic poles wander chaotically, and apparently flip completely from time to time?

        Even though the Earth’s rotation has been slowing in fits and starts, recently it seems to have sped up, and nobody can say why, with any certainty.

        Self styled climate scientists (and their bizarrely unrealistic models) cannot even describe the GHE which they seem to believe in, in any examinable way, let alone explain the movements of the lithosphere, aquasphere and atmosphere. Many of them seem to have a simplistic view of the physical world, and reject fact in favour of fantasy.

        I assume that chaos is the rule of Nature, and that the approximate present is no guide to the approximate future.

        Climate science? A contradiction in terms. Oh well.

      • Nate says:

        “I assume that chaos is the rule of Nature’

        Yes, we are well aware of your ignorance about science and your knee-jerk dismissals of it.

      • Nate says:

        The Earth has varying climates.

        AND the Earth has a global water average vapor content that changes with global average temperature.

        You suggest these two things cannot both be true, without evidence.

      • Dixon says:

        I’m suggesting global average anything is useless information.

      • Swenson says:

        Nate,

        Putting your silly words in my mouth won’t help.

        I suggest nothing, except that nobody can even describe the GHE in any that allows for scientific scrutiny.

        Just repeating that climate changes, and making silly assumptions about water vapour doesnt make you look particularly brilliant. As I have pointed out, hottish places like Furnace Creek in Death Valley, or the Lut desert do not raise the amount of water vapour in the atmosphere above them.

        So carry on, make your silly unsupported assertions and opine away.

        Nature doesn’t care, and neither do I.

      • Nate says:

        “hottish places like Furnace Creek in Death Valley, or the Lut desert do not raise the amount of water vapour in the atmosphere above them.”

        Repeating the same non-relevant facts makes them no more relevant than they were before.

        Oh well!

      • Nate says:

        “Im suggesting global average anything is useless information.”

        Useless for you does not = useless for science.

      • Dixon says:

        “Useless for you does not = useless for science”

        And that, really, is the problem with Climate ‘science’. It’s divided the world into three groups:
        1. Those that think global averages mean something.
        2. Those that think global averages are a terrible proxy for important things.
        3. Those that really don’t care.

        If you can produce some evidence outside of climate science to show global averages are useful I will consider changing my mind.

      • Nate says:

        “If you can produce some evidence outside of climate science to show global averages are useful I will consider changing my mind.”

        Why outside of science?

        As you can see by this blog, it is based around measurements of global temperature, and indeed science needs that data to compare to and test climate models.

        If climate models cannot account for global T as observed, then the models need to be revised.

      • Swenson says:

        Nate,

        Stop distorting. Outside of “climate science”, as opposed to science.

        You can’t describe “climate science” any more than you can describe the GHE. Climate is the historical statistics of weather observations. Not much science there.

        Climate models are useless – you cannot produce even one which is correct.

        If you could at least respond to what people say, rather than what you wish they had said, people might assign some value to them.

        Keep pounding that keyboard.

      • Nate says:

        “If you could at least respond to what people say”

        I did, but you are not here to inform, just to whine.

  16. Ireneusz Palmowski says:

    Snowfall in Alaska will begin. Snow also in the Rocky Mountains.
    https://i.ibb.co/TWWkcjW/mimictpw-alaska-latest.gif

  17. Ireneusz Palmowski says:

    It promises to be an interesting autumn in North America.
    https://i.ibb.co/hmjMgJJ/gfs-o3mr-200-NA-f120.png

  18. Nabil Swedan says:

    There is no climate sensitivity in the real world. That is why it has been difficult to pinpoint.It is a fictional byproduct of the the mind-created greenhouse gas effect.

  19. Nabil Swedan says:

    I finally see climatologists correlate climate parameter with population density. This is a good start. Population on the other hand alters photosynthesis products such as deforestation, fossil fuels, and surface greening. Climate change is all about photosynthesis mass and heat balance, which may not be a surprise to many.

  20. Richard M says:

    As I mentioned on WUWT, this value is likely quite reasonable for the warming effect of CO2. However, since it doesn’t include the cooling effect of CO2, it has nothing to do with climate sensitivity for the doubling of CO2.

  21. As for “the official *theoretical* model-based IPCC range of 2.5 to 4.0 deg. C”: This sounds to me as CMIP6 models, which went wayward with extra warming, while the CMIP 3 & 5 models were starting to show they mostly slightly overpredicted surface warming and greatly overpredicted warming of the tropical upper troposphere. I suspect the CMIP 3 & 5 models got worked with a bad assumption that the cloud albedo is positive with the water vapor feedback being what it would be with unchanged relative humidity. But: I see that as increased water vapor increases ability of water vapor to move heat, a result is cloudy updrafts shrinking in planet coverage and clear downdrafts increasing their planet coverage, which means decrease of average tropospheric relative humidity coming along with decrease of cloud cover.

  22. Ireneusz Palmowski says:

    The amount of heat in the tropical Pacific Ocean is falling. This is current data, not a forecast.
    http://www.bom.gov.au/archive/oceanography/ocean_anals/IDYOC006/IDYOC006.202310.gif

  23. David Overton says:

    I don’t find the 1.9 C figure comforting. At our current rate of CO2 increases (about 25 ppm per decade), we will have doubled CO2 within 5 decades, likely bringing us very close to 2 degrees C of warming.

    Now that we have this data, failing to act aggressively to reduce CO2 emmissions is irresponsible. Any disagreement with that?

  24. Dave Burton says:

    David O, let not your heart be troubled. Global warming is nothing to worry about.

    Although the CO2 level has increased by 50% (from about 280 ppmv to 420 ppmv), that means, in terms of radiative forcing, we’ve already seen 58.5% of a doubling (log2(420/280)=0.585). That means another 140 ppmv increase in CO2 level (to 560 ppmv) would give us only 41.5/58.5 = 71% of the radiative forcing (warming effect) from CO2 which we’ve already seen.

    What’s more, it will be challenging to raise atmospheric CO2 levels that much. Natural CO2 removal processes are already removing >2.5 ppmv of CO2 per year, and those removal processes accelerate by 1 ppmv/year for every 40-50 ppmv rise in atmospheric CO2 concentration. That means if we continue emitting CO2 at the current rate, the atmospheric CO2 level would still plateau well below 560 ppmv.

    But if our (China’s!) CO2 emission rates continue to increase, we could get there, so let’s figure out what that would mean for climate.

    It is usually estimated that the average temperature of the Earth has increased by about 1.15 0.15 C since the late Little Ice Age (LIA). (The warming has been disproportionately at chilly high latitudes, and in winter, which is nice, because they’re much too cold, anyhow.)

    If we generously assume that that warming was entirely due to human GHG emissions (which I doubt), and assume that 80% of it was from CO2 (though Myhre 1998 estimated only 58%), that means 58.5% of a doubling of CO2 caused 0.81.15 = 0.92C of warming. So a full doubling of CO2 would cause 0.92C / 0.585 = 1.57C of warming.

    That’s an estimated upper bound for “practical climate sensitivity,” based on realized warming to date. It’s less than ECS, but greater than TCR. Assuming that it’s about midway between ECS and TCR, if ECS = 1.5TCR (a common estimate), that means:

    ECS = 1.2 1.57C = 1.884C
    TCR = 0.8 1.57C = 1.256C

    Note that the ECS figure is almost identical to the 1.9C reported by Spencer & Christy.

    But about 0.92C of that CO2-caused warming has already occurred, so 1.57 C or 1.884 C of warming doesn’t mean temperatures that much warmer than now. It means less than 1C of warming, compared to our current climate. (Note, too, that there’s a broad consensus among historians that the warming we’ve already seen since the LIA has been beneficial, overall.)

    Because of the logarithmically diminishing effect of additional CO2, if the CO2 level rises another 140 ppmv to 560 ppmv, that increase will give us only 71% of the radiative forcing from CO2 which we’ve already seen. Using the practical sensitivity upper bound of 1.57C per doubling (calculated above), we would get, at most, only (1.57-0.92) = 0.65C of additional warming due to that additional 140 ppmv of CO2 (420 → 560).

    That’s not worrisome. In fact, it would probably be net beneficial, just as the warming which we’ve already seen since the LIA has been beneficial. (That’s why scientists call the warmest climate periods “climate optimums.”)

    If the CO2 level were to remain at 560 ppmv for a few centuries, we’d presumably see the full ECS warming, i.e., at most (1.884-0.92) = 0.964C of additional warming due to CO2.

    Call it “about 1C.” That’s a very slight change.

    1C is the temperature change you get from an elevation change of about 500 feet. (That’s calculated from an average lapse rate of 6.5C/km.)

    At mid-latitudes, 1C is about the temperature change you get from a latitude change of around 60 miles.

    In the American Midwest, farmers can fully compensate for a 1C temperature change by adjusting spring planting dates by about six days.

    In fact, 1C is less than the hysteresis (a/k/a the 2-3F “dead band” or “dead zone”) in a typical home thermostat, which is the amount that your indoor temperatures go up and down, all day long, without you even noticing it.

    For the climate industry to pretend that such a tiny temperature change is an “emergency” is ridiculous. It’s not even a problem. The evidence is compelling that manmade Climate Change is modest and benign, CO2 emissions are beneficial rather than harmful, and the “social cost of carbon” is negative.

    • Dave Burton says:

      Unfortunately, all my special characters (°, ×, ±) disappeared in my comment. So I’m going to re-post it with &entity; syntax, to try to fix it. Roy, if that works, please feel free to deleted the garbled one.

    • Nate says:

      “Natural CO2 removal processes are already removing >2.5 ppmv of CO2 per year, and those removal processes accelerate by 1 ppmv/year for every 40-50 ppmv rise in atmospheric CO2 concentration.”

      That’s not at all obvious.

      The ‘removal’ is not necessarily permanent.

      So when 5 ppm are added to the atmosphere, 2.5 ppm rather quickly are shared with the fast-responding reservoirs, the biosphere, soil and surface ocean, but perhaps only a tiny fraction of this is removed permanently to the deep ocean, because the Revelle factor limits the uptake of carbon into the ocean.

      So these fast reservoirs already have a partial pressure of CO2 that is close to that of the atmosphere, so if the atmosphere partial pressure stops growing from new emissions, then these reservoirs will stop taking up 2.5 ppm annually from the atmosphere.

  25. Dave Burton says:

    (corrected version)

    David O, let not your heart be troubled. Global warming is nothing to worry about.

    Although the CO2 level has increased by 50% (from about 280 ppmv to 420 ppmv), that means, in terms of radiative forcing, we’ve already seen 58.5% of a doubling (log2(420/280)=0.585). That means another 140 ppmv increase in CO2 level (to 560 ppmv) would give us only 41.5/58.5 = 71% of the radiative forcing (warming effect) from CO2 which we’ve already seen.

    What’s more, it will be challenging to raise atmospheric CO2 levels that much. Natural CO2 removal processes are already removing >2.5 ppmv of CO2 per year, and those removal processes accelerate by 1 ppmv/year for every 40-50 ppmv rise in atmospheric CO2 concentration. That means if we continue emitting CO2 at the current rate, the atmospheric CO2 level would still plateau well below 560 ppmv.

    But if our (China’s!) CO2 emission rates continue to increase, we could get there, so let’s figure out what that would mean for climate.

    It is usually estimated that the average temperature of the Earth has increased by about 1.15 ±0.15 °C since the late Little Ice Age (LIA). (The warming has been disproportionately at chilly high latitudes, and in winter, which is nice, because they’re much too cold, anyhow.)

    If we generously assume that that warming was entirely due to human GHG emissions (which I doubt), and assume that 80% of it was from CO2 (though Myhre 1998 estimated only 58%), that means 58.5% of a doubling of CO2 caused 0.8×1.15 = 0.92°C of warming. So a full doubling of CO2 would cause 0.92°C / 0.585 = 1.57°C of warming.

    That’s an estimated upper bound for “practical climate sensitivity,” based on realized warming to date. It’s less than ECS, but greater than TCR. Assuming that it’s about midway between ECS and TCR, if ECS = 1.5×TCR (a common estimate), that means:

    ECS = 1.2 × 1.57°C = 1.884°C
    TCR = 0.8 × 1.57°C = 1.256°C

    Note that the ECS figure is almost identical to the 1.9°C reported by Spencer & Christy.

    But about 0.92°C of that CO2-caused warming has already occurred, so 1.57 °C or 1.884 °C of warming doesn’t mean temperatures that much warmer than now. It means less than 1°C of warming, compared to our current climate. (Note, too, that there’s a broad consensus among historians that the warming we’ve already seen since the LIA has been beneficial, overall.)

    Because of the logarithmically diminishing effect of additional CO2, if the CO2 level rises another 140 ppmv to 560 ppmv, that increase will give us only 71% of the radiative forcing from CO2 which we’ve already seen. Using the practical sensitivity upper bound of 1.57°C per doubling (calculated above), we would get, at most, only (1.57-0.92) = 0.65°C of additional warming due to that additional 140 ppmv of CO2 (420 → 560).

    That’s not worrisome. In fact, it would probably be net beneficial, just as the warming which we’ve already seen since the LIA has been beneficial. (That’s why scientists call the warmest climate periods “climate optimums.”)

    If the CO2 level were to remain at 560 ppmv for a few centuries, we’d presumably see the full ECS warming, i.e., at most (1.884-0.92) = 0.964°C of additional warming due to CO2.

    Call it “about 1°C.” That’s a very slight change.

    1°C is the temperature change you get from an elevation change of about 500 feet. (That’s calculated from an average lapse rate of 6.5°C/km.)

    At mid-latitudes, 1°C is about the temperature change you get from a latitude change of around 60 miles.

    In the American Midwest, farmers can fully compensate for a 1°C temperature change by adjusting spring planting dates by about six days.

    In fact, 1°C is less than the hysteresis (a/k/a the 2-3°F “dead band” or “dead zone”) in a typical home thermostat, which is the amount that your indoor temperatures go up and down, all day long, without you even noticing it.

    For the climate industry to pretend that such a tiny temperature change is an “emergency” is ridiculous. It’s not even a problem. The evidence is compelling that manmade Climate Change is modest and benign, CO2 emissions are beneficial rather than harmful, and the “social cost of carbon” is negative.

    • Nate says:

      “(Note, too, that theres a broad consensus among historians that the warming weve already seen since the LIA has been beneficial, overall.)”

      Really? Can you show us where this comes from?

    • Nate says:

      This ignores the fact that the amount of warming from the LIA to the 20th century, was much much less that the T gradient from N. to S. Europe.

      There is no evidence that the southern parts of Europe have always done better than the northern parts of Europe (e.g. Spain Greece and Italy vs Netherlands, UK, and Germany). In fact lately the southern parts of Europe have been experiencing devastating heat waves and drought conditions.

      This also ignores the fact that our modern civilizations developed in various climates, over a period of centuries with relative climate stability, with cities and agricultural belts arising in places with predictable water sources, weather, and stable coastlines.

      So one could argue that climate stability is the preferred climate condition for human civilization.

      It also ignores the fact that much of the population is now in the tropics and would not benefit at all from additional warmth.

    • David Overton says:

      Thank you for the thoughtful reply to my comment. I suspect we will just have to agree to disagree.

      Despite your explanation, I am still concerned, and here is why: I have closely followed the climate change discussion since the 1990’s and here is what I observed from my perspective. First, those questioning climate change questioned whether warming was occurring at all – the measurements were bad, the trends were not clear. But that is no longer a debate. Dr. Spencer’s data is pretty clear on that. Then they said “ok, it’s warming, but humans aren’t the cause”. That has also gone by the wayside, as now virtually all climate scientists agree that human activity is the major driver (e.g. https://www.climate.gov/news-features/climate-qa/are-humans-causing-or-contributing-global-warming).

      So now, the frequent claim is “it won’t be a problem”. That is largely a claim about the future, and it is hard to know what will happen. I am a layperson in this area, so I tend to rely on relevant experts. And the vast majority of them are clear that continued warming is a serious threat. (for example, https://www.nationalgeographic.com/science/article/why-climate-change-is-still-the-greatest-threat-to-human-health). The DOD also identifies climate change as a serious risk as well (https://www.defense.gov/spotlights/tackling-the-climate-crisis/). And, we are already seeing adverse affects from warming to date (e.g. https://climate.nasa.gov/effects/).

      But this is a complex topic (as Yogi Berra may have said, “predictions are difficult, especially about the future”!), and I will agree that there is a chance that you could be right and the experts could be wrong, and that temperature increases may slow, and/or that warming may not be too bad. But I believe the probability is far higher that the majority of experts are right and that the risk associated with ignoring climate change is unacceptable. I remain seriously concerned.

    • Swenson says:

      Nate wrote –

      “It also ignores the fact that much of the population is now in the tropics and would not benefit at all from additional warmth.”

      Much? It’s around 40%, but who can say more than 50% of these would not benefit from “additional warmth”? What about the majority who do not live in the tropics? Don’t they count?

      If additional warmth is supposed to increase rainfall, those people suffering from drought in the arid tropical regions might indeed benefit.

      Once again, Nate babbles, hoping that others will accept his speculations as fact.

      Some people claim that “climate stability” is a preferred goal – locking the present inhabitants of Siberia, or arid desert wastelands, into their present less-than-wonderful lifestyles.

      Nonsense. The climate always changes – unpredictably. That’s reality, whether we like it or not.

      Nutters like Nate can believe what they want.

      • Nate says:

        “If additional warmth is supposed to increase rainfall,”

        If pigs could fly… If Swenson had a brain…

        Swenson’s possibilities are not useful facts.

      • Swenson says:

        If you say so, Nate, if you say so.

        Others can make up their own minds.

  26. Dixon says:

    Outside of CLIMATE science. FFS!

    Ill take statistics if you like, but if must be global and useful

  27. Dixon says:

    What data concerns you?
    I too have followed climate since the 90s. The late 80s in fact!
    Since then, warming has been significantly less than predicted and C02 emissions at, or above predictions.
    The ability of humans to pour scorn on each other and support dictators scares me far more than a bit of warming that may be due to fossil fuels.

  28. Guido Gramel says:

    Hello everybody, Mr. Spencer,

    my english is not good but i try to ask you my question.
    Did you hear about the theory/thesis that the outbreak of the vulcano in tonga is the reason for the record-temperatures. With the eruption there comes a load of Water in to the stratosphere and spread around the globe. Because of the warming effect of water in this layer there are now high average-temperatures. What do you think of that thesis and what maybe can be the effects to the actual discussion of climate change?

    Mit freundlichen Gren 😉