Summer warming 1895-2023 in U.S. cities exaggerated by 100% from the urban heat island effect

September 26th, 2023 by Roy W. Spencer, Ph. D.

We are now getting close to finalizing our methodology for computing the urban heat island (UHI) effect as a function of population density, and will be submitting our first paper for publication in the next few weeks. I’ve settled on using the CONUS (Lower 48) U.S. region as a demonstration since that is where the most dense network of weather stations is. We are using NOAA’s V4 of the GHCN monthly dataset.

I’ve previously described the methodology, where I use many thousands of closely-spaced station pairs to compute how temperature between stations change with population density at 10×10 km resolution. This is done for 22 classes of 2-station average population density, and the resulting cumulative UHI curves are shown in Fig. 1.

Fig. 1. Cumulative urban heat island effect in different multidecadal periods for the contiguous U.S. (CONUS), June/July/August, for GHCN monthly average ([Tmax+Tmin/2]) temperatures calculated from regression of station-pair differences in temperature vs. population density in 22 classes of 2-station average population density. The number of station pairs used to compute these relationships ranges from 210,000 during 1880-1920 to 480,000 during 2000-2010.

It is interesting that the spatial (inter-station temperature difference) UHI effect is always stronger in the homogenized GHCN data than in the raw version of those data in Fig. 1. The very fact that there is a strong urban warming signal in the homogenized data necessitates that there must be a UHI impact on trends in those data. This is because the urban stations have grown substantially in the last 130 years. A recent paper by Katata et al. demonstrates that the homogenization technique used by NOAA does not actually correct urban station trends to look like rural station trends. It does breakpoint analysis which ends up adjusting some stations to look like their neighbors, whether urban or rural. To the extend that spurious warming from UHI is gradual through time, it “looks like” global warming and will not be removed through NOAA’s homogenization procedure. And since all classes of station (rural to urban) have undergone average population growth in the last 130 years, one cannot even assume that rural temperature trends are unaffected by UHI (see Fig. 2).

Fig. 2. Cumulative growth in population density (PD) 1880-2015 at temperature monitoring stations in four classes of initial station urbanization, calculated by summing the average year-on-year increases in HYDE3.2 dataset population density at individual GHCN stations having at least two years of record in the 20°N to 80°N latitude band, for initial station PD of a 0 to 10, b 10 to 100, c 100 to 1,000, and d greater than 1,000 persons per sq. km initial station population density.

The regression estimates of change in temperature with population density (dT/dPD) used to construct the curves in Fig. 1 were used at each individual station in the U.S. and applied to the history of population density between 1895 and 2023. This produces a UHI estimate for each station over time. If I compute the area-average GHCN yearly summertime temperature anomalies and subtract out the UHI effect, I get a UHI-corrected estimate of how temperatures have changed without the UHI effect (Fig. 3).

Fig. 3. Lower-48 (CONUS) summertime U.S. temperature variations, 1895-2023, computed from GHCN “adj” (homogenized) data, versus those data adjusted for the urban heat island warming estimated from population density data.

The data in Fig. 3 are from my 1 deg latitude/longitude binning of station data, and then area-averaged. This method of area averaging for CONUS produces results extremely close to those produced at the NCDC “Climate at a Glance” website (correlation = 0.996), which uses a high resolution (5 km) grid averaged to the 344 U.S. climate divisions then averaged to the 48 states then area averaged to provide a CONUS estimate.

UHI Warming at Suburban/Urban Stations is Large

The UHI influence averaged across all stations is modest: 24% of the trend, 1895-2023. This is because the U.S. thermometer network used in Version 4 of GHCN is dominated by rural stations.

But for the average “suburban” (100-1,000 persons per sq. km) station, UHI is 52% of the calculated temperature trend, and 67% of the urban station trend (>1,000 persons per sq. km). This means warming has been exaggerated by at least a factor of 2 (100%).

This also means that media reports of record high temperatures in cities must be considered suspect, since essentially all those cities have grown substantially over the last 100+ years, and so has their urban heat island.


122 Responses to “Summer warming 1895-2023 in U.S. cities exaggerated by 100% from the urban heat island effect”

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  1. EventHorizon says:

    I always find it hilarious that people whose livelihoods depend on climate (ex: farmers) cannot be bothered about the “climate crisis”, but pencil pushers working in AC’ed buildings, driving AC’ed cars, living in AC’ed homes are scared to the point of neuroticism. I wonder who’s right…

    • Willard says:

      Right on:

      Climate change threatens the existence of humankind on the planet Earth. Owing to its arid climate and poor natural resources base, Saudi Arabia is particularly susceptible to the negative impact of ongoing climate change. Farmers understanding of this global phenomenon is extremely important as it may help determine their adaptation behavior. This study was designed to analyze farmers beliefs and concerns about climate change as well as their views about adaptation different obstacles. Data were collected from 80 randomly farmers of the Al-Ahsa region in Eastern Province using structured interviews. The findings revealed that farmers believed that climate change is mainly occurring due to anthropogenic activities. Drought, insects, crop diseases, and heat stress were their main concerns regarding adverse impacts of climate change. Lack of knowledge about adaptation practices, and poor government and financial support are perceived as the major obstacles to adaptation. The results of non-parametric analysis identified no significant differences in farmers climate change beliefs and concerns, and their views about obstacles to adaptation in relation to their demographic characteristics. Based on the findings, we suggest that capacity building programs should be undertaken by the government for enhancing the adaptive capacity of the farmers as well the provision of financial incentives wherever deemed necessary for promoting the adoption of sustainable agricultural practices and building a resilient national food system.

      https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9876375/

      Must be the UHI.

    • Arkady Ivanovich says:

      Life science company Bayer commissioned an agency to independently interview 800 farmers globally, representing farms large and small from Australia, Brazil, China, Germany, India, Kenya, Ukraine, and the United States in equal numbers.

      71% of farmers say that climate change already has a large impact on their farm, and even more are worried about the impact this will have in the future. 73% have experienced increasing pest and disease pressure. On average, farmers estimate that their incomes had reduced by 15.7% due to climate change in the past two years. One in six farmers even identifies income losses of over 25% during this period.

      Meanwhile, Greece’s agricultural heartland is under water – and recovery will take a long time.

      Athens is asking Brussels for aid after a violent storm brought record rainfall last week, turning the Thessalian plain – home to a quarter of the country’s agricultural production – into a vast lake.

      “We’ve had the worst floods in our history. This is probably one of the most powerful storms to ever hit Europe,” Prime Minister Kyriakos Mitsotakis said after meeting with European Commission President Ursula von der Leyen in Strasbourg on Tuesday.

      The region of Thessaly saw more than a year’s worth of rainfall in 48 hours, inundating the fertile plain at its center. According to the EU’s Copernicus monitoring service, some 73,000 hectares – an area nearly as large as New York City – are under water.

      With the plain accounting for 25 percent of Greece’s agricultural production, the threat of shortages and price hikes now looms large.

      Efthymios Lekkas, a disaster management expert, told state television that it would take at least five years for the plain to become fertile again.

      • Antonio says:

        I have heard that the global world crops are beating records, year after year ( like in https://ourworldindata.org/agricultural-production#interactive-charts-on-agricultural-production ). Interesting that farmers say they have losses in western countries. Maybe expecting some more subsidies?

      • Arkady Ivanovich says:

        “I have heard that the global world crops are beating records, year after year…”

        The EU Crop Monitoring Report September 18, 2023 says:

        The 3% downward revision of the yield forecast for grain maize at EU level is mainly due to a worsened outlook for summer crops in Romania, Bulgaria, and Greece.

        The worsened yield outlook for maize and sunflowers in Romania and Bulgaria is due to persistent drought conditions in large parts of these countries, which further compromised yield formation.

        In Greece, unprecedented floods resulted in a complete loss of summer crops in the Thessaly region, which accounts for 22% of the national production of grain maize. In Slovenia, following the floods reported in the August edition of the Bulletin, well above-average rainfall, including events exceeding 100 mm in some areas, led to additional flooding in fields with already saturated soils.

        Distinct heatwaves in the second half of August negatively affected the outlook for grain maize in part of eastern France (without affecting the outlook at national level), whereas similar conditions in north-western Italy mainly impacted grasslands and maize.
        Rain surplus continued to affect many parts of central and northern Europe, with negative impacts on summer crops (mainly due to increased disease pressure), as well as on the grain quality and yields of winter and spring cereals that could not be harvested on time.

  2. ghall says:

    California – population vs temp – UHIE

    I hope this links: https://wattsupwiththat.files.wordpress.com/2010/01/goodridge_1996_ca-uhi_county.jpg

  3. Arkady Ivanovich says:

    “… media reports of record high temperatures in cities must be considered suspect…”

    It isn’t just cities that are breaking temperature records though.

    The oceans are abnormally warm: https://imgur.com/a/eLWh8NS

    • Myron says:

      Do you have temperature data from 1895-2023 for the oceans? It would be improper to attempt to associate any recent warming of the oceans with over 100 years of city temperature data.

      • Arkady Ivanovich says:

        “Do you have temperature data from 1895-2023 for the oceans?”

        Yes. It is publicly available free of charge.

      • Roy Warren Spencer says:

        The oceans are a different subject. Yes, best estimates are that they have warmed… but the land has warmed more than 50% faster. In climate models, the land warms faster than the oceans, but by an amount less that what is observed. I think the land warming trend has been exaggerated due to urbanization, most of which homogenization algorithms cannot remove (it looks like global warming! how could they remove it??), which means the response to increasing CO2 (if that is the only cause) is not as large as we are being told, which means climate sensitivity over land is less than claimed. We have a press release regarding a just-published paper on some of this in the coming days.

      • Arkady Ivanovich says:

        The ocean has this huge ability to absorb heat.

        Hold your arms out wide, that is about the size of one cubic meter of air. To heat that air by 1 C, it takes about 1,200 joules. But to heat a cubic meter of ocean requires about 4,200,000 joules.

        By absorbing all this heat, the ocean lulls people into a false sense of security that climate change is progressing slowly.

      • Swenson says:

        A,

        At night, the ocean radiates all the heat it absorbed during the day.

        Warm water floats on top of colder, denser water.

        No heat hidden in the depths. That’s just being silly, and denying physical laws.

      • Denny says:

        A

        Except looking at the only direct measurements, that is the tidal gauge sea level rise, there is very little, if any, acceleration in the rate over the last 100 years. The predictions of the past have been miserable failures. How many more decades will we have to wait before the parabolic rise occurs.

      • Arkady Ivanovich says:

        “…the tidal gauge sea level rise, there is very little, if any, acceleration in the rate over the last 100 years.”

        See sea level rise data here: https://www.epa.gov/system/files/images/2022-07/sea-level_download1_2022.png

    • Swenson says:

      A,

      You realise that the deep oceans are not heated by the Sun, do you?

      That is physically impossible. A fantasy shared by GHE cultists who should know better.

      -That’s like saying that a furnace cannot heat your house in winter, but of course it can because the air it heats is transported throughout the house. Similarly (but on a much longer time scale) the oceans slowly overturn, so the water warmed by the sun eventually sink to the bottom. It’s part of the global ocean heat budget. Also, and possibly more importantly on shorter time scales, there is vertical mixing between all ocean layers due to wind (near the surface) and tidally-forced flows over ocean bottom topography (for the deep ocean). So, yes, Swenson, the sun does heat the deep ocean. Read a textbook on basic physical oceanography.
      -Roy

  4. Tim S says:

    The data in Fig. 3 also show that the period from 1930 to 1940 was very warm. More interesting is how much variation there is in the raw data compared to some of the other published datasets that use data smoothing to show a steady progression of warming.

  5. Denny says:

    For me, the specifics are not as important as that we have found yet another reason to pause and reflect whether the establishment narrative has it right. The reasons for caution are piling up.
    For those living and researching the AGW issue in 2100, with much more knowledge than we currently possess, all these discoveries will be fascinating reading as they are revealed, one by one, in slow motion.

    • Anon for a reason says:

      Like you I wonder how history will treat the agw issue. Will new chapters be added to the psychology books about media manipulation or how cancel culture led by a few academics caused trillions to be spent. Will it be called the Mann Syndrome or people suffering from Willardness.

      Or will there be condemnation of scientists who believe that climate models were a pipe dream..

      Or economic & political books on social control.

      Time will tell.

      • Willard says:

        Something tells me you passed over less self-serving possibilities, dear Anon.

        For instance, have you ever wondered that, if our models were a pipe dream, that’s because our climate would go beyond the ballpark they estimated? Or perhaps that the “trillions” you pay lips service to are being invested somewhere and put to good use?

        You got a point, however. Now that Rupert is dead, media manipulation should take a small hit.

      • Swenson says:

        Not just gibberish, obscure gibberish.

        Well done.

      • Willard says:

        What are you braying about, Mike Flynn?

      • Stephen P Anderson says:

        It’s difficult to speak coherently when you’re a propagandist. At least Wiltard’s smart enough to realize.

      • Willard says:

        The point should not that hard to understand, Troglodyte.

        But since your stance rests on not getting it, it’s fine with me.

  6. Ken Gregory says:

    The paper by Katata et al. at the link given says the authors estimate the UHIE bias for the CONUS is about “20% of the long-term warming.” Figure 3 above shows the UHIE is 24%. I think Spencer’s method and result is more accurate. Katata et al also says that the population density is about 10 times than in the USA. They estimate the UHIE is about 60% of the long-term warming.

    This paper https://www.mdpi.com/2225-1154/11/9/179 by Soon, ConnolyX2 compare rural to rural+urban stations and estimated the Northern Hemisphere UHIE is about 40% of the all-station warming trend. That estimate is likely low because the rural stations also must have some UHIE.

    The paper https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/joc.1292 by De Laat and Maurellis 2006 estimated the land mean trend 1979 – 2001 is 0.2518 C/decade as measured and 0.129 C/decade without UHIE, so the UHIE is 49% of the measured trend over land.

    The paper https://www.rossmckitrick.com/uploads/4/8/0/8/4808045/m_m.jgrdec07.pdf by McKitrick and Michaels 2007 with discussion at http://icecap.us/images/uploads/MM.JGR07-background.pdf shows that over 1979-2002, the measured land trend is 0.30 C/decade and without UHIE is would be 0.17 C/decade, so the UHIE is 52% of the measure trend over land.

    • Ken Gregory says:

      In my first paragraph, it should be “Katata et al also says that the population density in Japan is about 10 times that in the USA.”

      • I think it’s clear the whole UHI issue has been ignored for too many years, mainly because the alarmists don’t want anything to damage the AGW narrative. Sloppy science. I’m glad that a number of authors have now published evidence that UHI effects are still inflating land temperature trends. By just how much remains uncertain. This is progress.
        -Roy

      • Antonio says:

        Roy, your first graph is for summer only, as far as I can see. The rest is for all-year? is there any difference between winter and summer?
        Thank you for the interesting work.

  7. Swenson says:

    Whichever way you look at it, it seems that heat produced as a result of human existence is measurable.

    This would seem to go against the claims of GHE supporters who wax lyrical about the comparative amount of energy emitted by the Sun, compared with human energy production.

    Humans generate heat, much of it by burning hydrocarbons which in turn result in raised levels of CO2 and H2O in the atmosphere – the H2O and CO2 being minimum combustion products.. Some slightly slow people think that heat results from additional CO2 and H2O in the atmosphere, believing that correlation implies causation.

    Silly GHE cultists, for example.

    • There was a textbook written many years ago, European author (I don’t remember who) that showed human energy production is trivial compared to energy input from the sun, when averaged over large areas.
      -Roy

      • Swenson says:

        Exactly so, no denial here.

        However –

        “This energy flux is over two orders of magnitude less than the energy received by the Earth from the Sun, but as the solar energy is mainly reradiated into space, it has little effect on temperatures deeper than a few meters in the Earth. Effectively, transfer of solar energy controls the temperature of the Earth’s surface, internal heat controls the Earth’s internal temperatures. About 80% of the Earth’s present internal thermal energy is derived from radioactive decay of long-lived isotopes, primarily 232Th, 238U, 40K, and 235U (listed in order of decreasing importance). The remaining 20% is primordial heat of Earth formation and differentiation (Turcotte and Schubert, 1982). ”

        Just one of many peer-reviewed papers backed up by measurements and experimental data.

        I cannot understand why some people simply refuse to accept the fact that the Earth is now cooler than it was when the surface was molten, or the fact that measurements indicate that the Earth is losing energy at a rate of 40 tW or thereabouts. That’s not heating, that’s cooling.

        I applaud your open mindedness about human heat production in the form of UHI. You may be aware of other research which shows the same effect over island nations such as Japan and Britain after their respective industrial revolutions.

        Obviously, if nighttime minima are elevated, it would be difficult to ascribe this to the GHE, although some would try, I suppose. Human heat production is best noted in the absence of sunshine.

        Time will tell.

  8. gbaikie says:

    Berkeley Earth determined global average land temperature was about
    10 C.
    How much of 10 C is due to urban heat island effect?

    • Good question. Based upon our calculations so far, I’d say less than 1 deg. C, but more than 0.1 deg. C. We will have an estimate at some point.
      -Roy

      • gbaikie says:

        Ok.
        If it was more than 2 C, it would change things for me.

        But +/- 1 C is sort of “normal” error range kind of stuff.
        Or without UHI effect considered, the 10 C global land average was always for me at least +/- 1 C.

      • gbaikie says:

        And what get from Berkeley Earth is wider unknown with average ocean global temperature.
        [Which I guess is somewhere around 17 C. But seems sea ice whether counts as ocean or land is somewhat in the air.
        I count frozen ocean surface as “land”- but I would guess the Berkeley 10 C for land doesn’t do this.

        I would include as land, because it is land. And sea ice is something I consider important, and if included to ocean, it’s effect is “lost” in the average of large area of the warm ocean.
        But if want add as third thing, that could tell you a lot.

      • Entropic man says:

        Back of the envelope:-

        The UK mean annual temperature for 2022 was 10.03C.

        The UK is 6% urbanised.

        Assuming an UHI of 2C, the contribution of urbanisation to the UK mean temperature was 2*0.06=0.12C.

      • Entropic man says:

        The US is 3% urbanised.

        The mean average temperature is 11.9C, of which 2*0.03=0.06C is due to urbanisation.

  9. Stephen P Anderson says:

    >the very fact that there is a strong urban warming signal in the homogenized data……

  10. Curious George says:

    Just curious .. the maximum population density over 8,000/km2 in 1990 does not appear in later data.

    ?? Yes, it does… in the 2000-2010 data. Those population categories are not fixed… I adjust them somewhat based upon available data. Of course, in 1880-1920 data, there were few or no population densities that high… not enough to perform regressions.
    -Roy

  11. Everyone knows cities are a lot warmer than the surrounding rural areas. Especially in the summer. Yet a huge number of people live in those hot cities and some of the fastest growing US cities are in the hot South — Austin, Houston, Atlanta, Orlando, Tampa. Conclusion: Humans like the heat.

    With changes of measurement equipment, weather stations moving to airports, land use changes and UHI likely at BOTH rural and urban weather stations, the calculation of US warming from UHI is just as impossible as the calculation of US warming from CO2.

  12. Darwin Wyatt says:

    It seems to me another warming factor is the Venus effect caused by contrail clouds. If you ask me theyre trying to stall an ice age. Last winter nearly killed me so Im fine with that.

  13. Mark B says:

    [i]This also means that media reports of record high temperatures in cities must be considered suspect, since essentially all those cities have grown substantially over the last 100+ years, and so has their urban heat island.[/i]

    These are usually single station records, albeit across station changes through history. Whether the station is warmer because of greenhouse gases or because of UHI isn’t relevant to the record being broken. It does have implications for the messaging around those records.

  14. Walter says:

    One thing I’ve questioned for years now is why don’t we just get rid of all the bad data and just rollout a global CRN? It’s so much easier to do that because it will record effortlessly and there would be no need for these statistical procedures. Yet they won’t let go? That to me raises a red flag. We could have had like 2 decades worth of excellent data by now.

  15. gbaikie says:

    Causality and climate
    Posted on September 26, 2023 by curryja | 108 Comments

    Guest post by Antonis Christofides, Demetris Koutsoyiannis, Christian Onof and Zbigniew W. Kundzewicz

    On the chicken-and-egg problem of CO2 and temperature.
    https://judithcurry.com/2023/09/26/causality-and-climate/#more-30527


    JC comment: I find this analysis to be very interesting. The global carbon cycle is definitely unsettled science. I think what this paper shows is that CO2 is an internal feedback in the climate system, not a forcing (I think that Granger causality would reveal this?). Yes, this all depends on how we define the system, and humans and their emissions are currently acting outside of the system in most climate models and are considered as an external forcing. Again, as emphasized in the paper, human emissions are small fraction of natural emissions so this issue of internal versus external isnt straightforward. By analogy, in the 1970s climate models specified cloud cover, and hence clouds acted as an external forcing. However, clouds vary in response to the climate, and now with interactive clouds, clouds are now correctly regarded as a feedback and not a forcing.

    • Entropic man says:

      “human emissions are small fraction of natural emissions”

      That turns out not to be the case.

      Total circulating carbon is about 2000Gt. Of that about half is in the atmosphere and the rest in the oceans and biomass.

      About 300Gt is emitted to the atmosphere by diffusion and respiration each year. This is balanced by 300Gt absorbed from the atmosphere by diffusion and photosynthesis.

      Net circulating carbon is constant. Net natural emission to the atmosphere is zero.

      Human emissions are about 6Gt/year. This is adding to the circulating carbon. 6Gt is enough to increase atmospheric carbon by 4ppm/year. Distributed between the three reservoirs it increases atmospheric CO2 by 2ppm/year.

      All of the increase comes from our emissions.

      • Anon for a reason says:

        Why do you believe that the “net circulating carbon is constant”?
        Where once there was marsh land there are towns & cities. Where once there are forests there are construction sites.

        Nothing is n nature is really constant, it is constantly changing albeit slowly.

      • Entropic man says:

        I was talking about the natural fast carbon cycle, which stays fairly constant.

        In the geological long term a small amount, about 0.05Gt/year, is added by volcanoes and removed again in sediments.

        In the mid-term cooling into a glacial period removes some CO2 into peat bogs, and releases it again when you enter an interglacial.

        In modern times none of the natural changes are acting. Artificial changes dominate. As you mention, changes in land use change the balance, increasing circulating CO2. So does removing carbon from geological storage as fossil fuels and burning it.

        There is also an expected positive feedback. As the climate warms permafrost thaws and decays. This will amplify the rate of rise in CO2 and the rate of temperature rise.

      • WizGeek says:

        What is the CO2 cycle modification when an ice starts and when an ice age ends? What cosmological processes contribute to the CO2 cycle? (And don’t bore me with Milankovitch obfuscations.)

      • Entropic man says:

        Tundra(basically a peat bog that covers the whole landscape) forms a ring around the Arctic outside the ice sheets. When the climate cools the the area of tundra increases and it takes CO2 out of the air. Much of this then ends up under the ice sheets as they expand South or frozen as permafrost. The total tundra biomass forms a big carbon sink.

        CO2 reduces from 280ppm to 200ppm, ice albedo increases and temperatures cool by 5C.

        When warming begins the frozen tundra thaws and releases CO2 as it decays. The ice sheet edge retreats North and uncovers more tundra. CO2 increases from 200 to 280ppm, ice albedo decreases and temperatures warm by 5C.

      • Swenson says:

        So the “climate” changes, and CO2 is released, is that it?

        You wrote – “When warming begins the frozen tundra thaws and releases CO2 as it decays.”

        What causes this “warming”?

        Doesn’t sound as though any GHE is involved. Is that really want you meant to say, or did you really mean to say something else?

      • Entropic man says:

        You get an interglacial when the Summer is warm enough to melt the snow that fell during the Winter.

        You get a glacial period when there is not enough summer heat to melt the snow. Then each year the thickness of the snow increases until you have new ice sheets.

        Those who study glacial cycles reckon that the glacial/interglacial switch is the amount of sunlight at 65N latitude. This varies over a 100,000 year, as do glacial cycles.

      • Swenson says:

        Ent,

        So the amount of sunlight at 65N determines the amount of CO2 in the atmosphere, is that it?

        Seems fair, if somebody reckons it is so.

        No GHE, then. Just natural cycles.

      • Entropic man says:

        ” So the amount of sunlight at 65N determines the amount of CO2 in the atmosphere, is that it? ”

        Under natural conditions, yes.

      • Swenson says:

        Ent,

        So when does the amount of sunlight at 65N NOT affect the amount of CO2 in the atmosphere?

        Or are you saying that the amount of CO2 in the atmosphere creates warming which affects the amount of CO2 in the atmosphere?

        All very confusing, in view of the fact that you intimate that cooling removes CO2 from the atmosphere. Nature managed to remove lots of CO2 from the atmosphere and turn it into fossil fuel. What harm does it do to put it back? You realise that removing CO2 from the atmosphere (as a lot of genocidal GHE enthusiasts want) would result in the extermination of all oxygen breathing life on the planet, I hope.

        You seem to be saying that the amount of sunlight at 65N determines glacial and interglacial cycles, except when CO2 does – or something.

        Maybe you could just describe the GHE, and let people make up their own minds.

        By the way, what do you think the optimal level of CO2 in the atmosphere is, and why? You don’t really know, do you?

      • Stephen P Anderson says:

        That’s Ant’s bog math.

      • Entropic man says:

        I’m not surprised you find it confusing. Out of your depth, again.

      • The Original Milankovitch Cycle states:

        “You get an interglacial when the Summer is warm enough to melt the snow that fell during the Winter.

        You get a glacial period when there is not enough summer heat to melt the snow. Then each year the thickness of the snow increases until you have new ice sheets.”


        The Reversed Milankovitch Cycle states:

        You get an interglacial when Winter on North Hemisphere occurs close to Earth’s Perihelion. The Southern Hemisphers’s vast oceanic waters are tilted towards the sun, when Earth is at its closest to the sun.

        Thus, as it occurs in our era, during the North Hemisphere’s warmer Winter, the very much hotter Southern Hemispher’s SUMMER oceanic waters are heavily accumulating, and that is why we observe the current Global Warming.

        https://www.cristos-vournas.com

      • Swenson says:

        But don’t the “emissions” come from burning hydrocarbons originally formed by removing CO2 from the atmosphere and forming fossil fuels?

        All part of the natural process.

      • Willard says:

        You got a point there, Mike.

        What is anthropogenic is also natural.

        In the end, all you got is silly semantic games.

  16. Anon for a reason says:

    Good to see that the UHI effect on climate records is being refined. Anyone who commutes knows of the UHI and the roughs scale of it.

    But somehow certain people are all too eager to dismiss this. Wonder why?

    • Willard says:

      Dismiss what, Anon – the heat that accumulates where people are?

      That about half of the murican states are “suburban” according to Roy’s definition:

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

      ? That the more terrain that definition covers, the less is to extrapolate over?

      So many questions, so little time.

      • Swenson says:

        Willard,

        Heat does not accumulate.

        That’s just silly.

      • Willard says:

        Mike Flynn,

        Please remind us what “UHI” stands for.

        Cheers.

      • Swenson says:

        Weird Wee Willy,

        Don’t you know what UHI stands for?

        Tut, tut. You are an ignorant wee cultists, aren’t you?

      • Willard says:

        Mike Flynn,

        If you knew what “UHI” stands for, you would not say that heat does not accumulate.

        Cheers.

      • Swenson says:

        Weird Wee Willy,

        Dont you know what UHI stands for?

        Tut, tut. You are an ignorant wee cultists, arent you?

      • Willard says:

        Mike Flynn,

        You ignorance is shining through:

        “An urban heat island (UHI) is an urban area that is significantly warmer than its surrounding rural areas due to human activities.”

        How can that happen if heat does not accumulate?

        Keep braying,

      • Swenson says:

        Willard,

        Do you really not know, or are you just being silly?

        You do realise that heat due to human activities is only there while humans are active. No accumulation – activities stop, heat stops.

        Are you really as ignorant as you appear?

      • Willard says:

        Mike Flynn,

        How do I know what – what Roy has been estimating and amplifying for decades?

        You are missing so much by not reading.

        Ah, well.

        Keep braying your irrelevant and ridiculous talking points!

      • Swenson says:

        How do you know what?

        I have no idea. It’s far too obscure for me. What has Roy Lumkin been estimating and amplifying for decades? Or do you mean Dr Roy Spencer?

        You’re not exactly a model of clarity, are you?

        Are you being intentionally obscure, or does it come naturally?

        Either way, it’s not surprising that nobody seems to value your opinion – nobody knows what it is!

        Carry on.

  17. Arkady Ivanovich says:

    Roy W. Spencer, Ph. D. wrote:

    “I think it’s clear the whole UHI issue has been ignored for too many years…”

    The UHI issue has not been ignored.

    The UHI has been a focus area of study in Urban Climatology since Luke Howard first measured the phenomenon.

    Howard released his findings in a three-volume report titled The Climate of London, published between 1818 and 1833.

    He wrote:

    “… we find London always warmer than the country, the average excess of its temperature being 1.579 F.”

    The effect has since been studied with increasing levels of sophistication.

    • Anon for a reason says:

      Arkady, the phrase is a lexical ambiguity.

      Saying something is being ignored also means that the subject is not being study to the extent it needs to be. A bit like how the extinction rebellion folk claiming that climate change is being ignored.

  18. Arkady Ivanovich says:

    2023 is now officially the most expensive, most destructive wildfire season on record in B.C.

    According to the B.C. Wildfire Service (BCWS), a total of 2,217 fires have been detected this year, burning almost 25,000 square kilometres of trees, bush and grassland. That makes it B.C.’s worst season by land burned, easily surpassing the previous record of 13,540 square kilometres in 2018.

    The cost of fighting those fires is also significantly up, to approximately $770 million so far this year, more than the $649 million spent in 2017.

    On Thursday, the B.C. government said higher-than-projected costs to fight wildfires had contributed an additional $2.5 billion to the province’s projected deficit for this fiscal year.

    The government is projecting the total spend for the 2023/24 fiscal year to be $966 million.

    The majority of this year’s fires – approximately 71 per cent – have been sparked by lightning, while 23 per cent are human-caused, the fire service says.

    Underlying conditions of drought made B.C. particularly susceptible to wildfires this year, as tinder-dry conditions made it easier for flames to spread.

    Many fires are still burning, though the service says cooler temperatures are helping ease pressure on crews.

    • Arkady Ivanovich says:

      Reality cannot be ignored except at a price; and the longer the ignorance is persisted in, the higher and the more terrible becomes the price that must be paid.

      • Swenson says:

        A terrible price is being paid for the bizarre notion that a GHE exists, and has adverse consequences.

        Religion is not always a force for good.

    • Entropic man says:

      Gordon’s state taxes will be going up. Climate change is costing him money. :–)

      • Willard says:

        IF Bordo makes more than 22K, which is a stretch.

        Kennui perhaps would be hit, IF his financial advisor sucks as much as his scientific gurus.

      • Swenson says:

        If financial advisors could look into the future, they would not need to work for a living.

        Hucksters and fortune sellers – one and all.

      • Willard says:

        If Mike Flynn could stop braying, he’d have done so by now.

        Sky Dragon cranks – a bunch of sore losers.

      • Swenson says:

        If financial advisors could look into the future, they would not need to work for a living.

        Hucksters and fortune sellers one and all.

        You are right about the Sky Dragon cranks – silly enough to believe in a GHE which they can’t even describe.

        So Mike Flynn spurned your homosexual protestations of love, did he? I don’t blame him.

      • Willard says:

        Poor Mike Flynn,

        Unable to realize that wealth management does not rest on fortune telling.

        No wonder he’s still looking for a job.

      • Swenson says:

        If financial advisors could look into the future, they would not need to work for a living.

        Hucksters and fortune sellers one and all.

        You are right about the Sky Dragon cranks silly enough to believe in a GHE which they cant even describe.

        So Mike Flynn spurned your homosexual protestations of love, did he? I dont blame him.

      • Willard says:

        You already said that, Mike.

      • Swenson says:

        If financial advisors could look into the future, they would not need to work for a living.

        Hucksters and fortune sellers one and all.

        You are right about the Sky Dragon cranks silly enough to believe in a GHE which they cant even describe.

        So Mike Flynn spurned your homosexual protestations of love, did he? I dont blame him.

      • Willard says:

        Thanks for the editorial comment.

      • Swenson says:

        You are most welcome.

        It’s my pleasure.

    • Swenson says:

      Thanks for the news report.

    • Anon for a reason says:

      How many of the fires are due to climate, rather than arson?

  19. Swenson says:

    If financial advisors could look into the future, they would not need to work for a living.

    Hucksters and fortune sellers – one and all.

    • Willard says:

      Have you lost your footing, Mike Flynn?

      • Swenson says:

        If financial advisors could look into the future, they would not need to work for a living.

        Hucksters and fortune sellers one and all.

      • Willard says:

        You don’t need to repeat your comment, Mike Flynn.

        But if that soothes your soul, go ahead.

      • Swenson says:

        If financial advisors could look into the future, they would not need to work for a living.

        Hucksters and fortune sellers one and all.

        Mind you, there is a never ending supply of suckers like you – falling over themselves to give the fortune sellers their money. Pitiable. Someone said that nobody ever went broke underestimating the intelligence of the American public.

        The future is unpredictable, and it hasn’t happened yet.

      • Willard says:

        Thanks for the editorial comment.

      • Swenson says:

        You are most welcome.

        It’s my pleasure.

  20. Anon for a reason says:

    Have you ever travelled throught Greece? I have and was amused by all the flood defenses 100 of meters above sea level.

    The country has thousands of dry river beds that only flow during heavy rain. Culverts and huge gutters by the roads can divert inches of rain safely away from the road surface. Their whole infrastructure has evolved to cope with their climate.

    Of course why would the Greek politicians avoid using climate change as an excuse to get money from Brussels.

    • Arkady Ivanovich says:

      Whatever point you’re trying to make, I hope it isn’t that the region of Thessaly did not see more than a year’s worth of rainfall in 48 hours, inundating the fertile plain at its center.

      If that’s your point, then, show your data.

      • Arkady Ivanovich says:

        More intense rainfall is one of the longest standing predicted impacts of climate change.

      • Anon for a reason says:

        Arkady, so you haven’t been to Greece yourself but instead rely on the news for your data. Do I really need to point out the folly of that.

        To put it bluntly the infrastructure of Greece, like many countries, is based on withstands 99% of extreme weather. To withstand 99.9% would be a magnitude more expensive, and to withstand the 99.99% would be another magnitude of expense.

        Although the flooding is regrettable, it’s not exactly unexpected.

      • Arkady Ivanovich says:

        So, you’re not denying that the region of Thessaly received more than a year’s worth of rainfall in 48 hours, inundating the fertile plain at its center. That is the issue at hand! I’m not interested in your strawman.

        FYI, I own (through one of my companies) a concession in the Ionian Sea, West of Corfu Island. Prior to that, I worked in the Gulf of Kavala in Northern Greece.

      • Anon for a reason says:

        Arkady, unless I see the data I don’t either deny or confirm claims made by others.

        Btw, it’s not a strawman but perhaps it’s a bit too subtle for you. Putting it a bit more bluntly: to make infrastructure capable of withstanding any natural rainfall event it would cost far too much. Name one infrastructure project that can withstand all natural events. fukushima certainly wasnt.

        You also seem to be oblivious of the world around you that you don’t see the massive dry river beds around Greece.

      • Arkady Ivanovich says:

        As I said before, whatever point you’re trying to make, I hope it isn’t that the region of Thessaly did not see more than a year’s worth of rainfall in 48 hours, inundating the fertile plain at its center.

        Because… data: https://imgur.com/a/V2DwwLq

        I’m done with your starwmen and red herrings.

      • Swenson says:

        A,

        I hope you are not claiming that the fact that Thessaly experienced a lot of rain is due to CO2 in the atmosphere.

        Next thing you will be claiming that severe drought is due to CO2 in the atmosphere.

        Or hurricanes. Or earthquakes. Or pleasant weather.

        Monstrously silly, isn’t it?

        The atmosphere is chaotic. Extremes are normal.

        Carry on.

      • Willard says:

        Mike Flynn,

        I hope you are realizing that you are ankle biting in a thread started by an anonymous commentator who happens to know about Greek hydrology.

        Cheers.

      • Swenson says:

        Willard, hope in one hand, urinate in the other.

        See which fills up first.

        You cannot find any facts to rebut what I said, so you try silly diversions.

        Good for you.

      • Willard says:

        Mike Flynn,

        You made only one claim, almost a definition –

        The atmosphere is chaotic.

        Why should anyone refute it?

      • Swenson says:

        Willard,

        What are you blabbering about?

        If you don’t want to refute something, don’t do it. What’s the point of asking me why you do what you do?

        You are a strange one, Willard.

  21. Anon for a reason says:

    Post was aimed at Arkady in reference to Greece.

    Btw why fo the replies randomly appear at the end?

  22. Anon for a reason says:

    @Willard, yes I have wondered if the models are under representing agw. But surely there would be evidence, which does seem to be missing.

    If anything the work of Dr Spenser and others would indicate that the current models are excessively sensitive, so totally over represent the issues.

    • Willard says:

      > But surely there would be evidence

      Evidence usually works better for the past, dear anon. Have you considered the Permian?

      I’m sure you can find lower models than Roy’s, though in fairness 1.9C is quite impressive, considering that 2C is the ultimate limit in justified disingenuousness.

      Probly just a coincidence.

      • Swenson says:

        Silly Willy,

        Have you considered the Hadean?

        Which of your thousands of useless models shows that the Earth cooled, and continues to do so?

        Look at the facts – if the model doesn’t agree, discard the model, it’s useless.

        You agree, surely?

      • Willard says:

        Mike Flynn,

        Yes, I actually did.

        Did you have in mind when there was a thick CO2 and CH4 rich atmosphere, or after oceans were formed?

      • Swenson says:

        Willard,

        You don’t have a model which fits the facts, do you?

        Keep bobbing and weaving. It won’t do you any good.

      • Willard says:

        Mike Flynn,

        Which fact from the Hadean was obtained through direct observation, again?

      • Swenson says:

        Willard,

        You dont have a model which fits the facts, do you?

        Keep bobbing and weaving. It wont do you any good.

        If you don’t want to believe the surface was once molten, good for you. You can live in any fantasy world you choose.

  23. Anon for a reason says:

    Willard, you say that 2C is the limit so it is ok for Dr Roy Spenser’s work to show a lower limit of 1.9C. You seem to miss the point that the 2C is 100% political, where as Dr Roy Spenser is using science. Be g difference.

  24. creon levit says:

    Hi there. I am loving your book “The Great Global Warming Blunder” and am glad to see you are publishing what amounts to “updates” here.

    You might find this little bit of data analysis I did (link below) interesting. Particularly the two stations in Oregon, Portland and Camp Pendleton, relative close to each other. Oregon with a lot of urban development over ~80 years, and Camp Pendleton without much development.

    Search the page for “Oregon”:
    https://creon.substack.com/p/hot-or-not