By Jo Nova
Nearly every plea for carbon subsidies depends on “the Social Cost of Carbon”, and it’s wrong
Every ton of carbon dioxide we emit is supposedly going to cause $220 USD in losses in the future, which justifies throwing lots of money at efforts to reduce emissions — like subsidizing EVs and solar panels, and inventing cricket burgers. This is called the Social Cost of Carbon (SCC). But half of that imaginary cost was the devastation higher temperatures would theoretically wreak on agriculture — which doesn’t make sense given that plants eat CO2 for breakfast. But for years bureaucrats and scientists have been telling us the damage in crops was going to cost $102USD per ton of carbon, and investors and politicians have been feeding that into their cash registers, and it’s all wrong.
Ten years ago Challinor et al did a big meta-review of crop changes with temperature, using 1,722 records, but many of these records had no figures for CO2 itself. And the whole point of calculating the social cost of carbon really depends on calculating what happens when CO2 rises, and supposedly causes temperatures to rise too. In 2017 Moore et al took those numbers and simulated them into gloom and doom scenarios which the Biden team converted into a fivefold increase in the “cost of carbon”. So Ross McKitrick took the same data from 2014, and then used an estimate of Equilibrium Climate Sensitivity (ECS) of about 3 °C which is the standard IPCC type figure, and filled in a lot of the missing figures. After recalculating the crop yields at higher temperatures and higher CO2, he found that the benefits of the extra CO2 outdid any downsides of warmer temperatures.
Ross McKitrick shows that even in the unlikely (unbelievable) event that CO2 causes five degrees of warming — it is not going to reduce crop yields.
Billions of dollars has been spent based on the idea that all CO2 emissions are bad, and there is a “social cost of carbon”, but if CO2 increases crops (and farmers already pump it into greenhouses because it does) — then there goes half the “social cost of CO2”. Indeed, increasing crops must add wealth, pushing the net cost figures down even further.
Indeed, if we could arrange another degree or two of warming we could increase corn, rice and wheat by 5 or 10%. It is inhumane to deny the hungry people of the world, so obviously, any responsible civilization should be emitting more CO2. Go forth and drive your pick-up truck, buy that SUV, the boat and the private jet. Do it for the children. 🙂
McKitrick (2025). “Extended crop yield meta-analysis data do not support upward SCC revision”. Sci Rep 15, 5575. Edits were made to the heading by me.
C3 crops like wheat, soybeans and rice ought to benefit the most from extra CO2. C4 crops, like corn and sorghum (top left graph) have evolved to make the most of lower CO2 levels already so will get less of an advantage if CO2 returns to it’s former higher levels. The newer C4 pathways give such a growth advantage, allowing plants to thrive in hotter and drier environments, that they independently evolved at least 45 times in the last 15 to 30 million years. The reason the C4 plants didn’t take over the world is that they need more sunlight and don’t thrive in cooler or shadier areas.
Willie Soon, Ronan and Michael Connolly discuss McKitricks paper below in the video. See also Vijay Jayaraj at the Daily Signal.
REFERENCES
McKitrick (2025). “Extended crop yield meta-analysis data do not support upward SCC revision”. Sci Rep 15, 5575.
Challinor, A. J. et al. A meta-analysis of crop yield under climate change and adaptation. Nat. Clim Change 4(4), 287 (2014).
Moore, F. C., Baldos, U., Hertel, T. & Diaz, D. New science of climate change impacts on agriculture implies higher social cost of carbon. Nat. Commun. 8, 1607. https://doi.org/10.1038/s41467-017-01792-x (2017).
One benefit not mentioned** is that extra CO2 could provide a buffer should the world retreat into an ice age again. We were done close to plant shutdown last time.
**because CO2 is regarded as evil by the Deluded CULT followers.
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We are in an Ice Age now – there is ice at both poles. Our milder temperatures for the last 12,000 years or so are because we’re in an interglacial period.
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Agreed, although there has been a long term (about 5,000 years) where the temperature has declined. Also that there are 2 definitions of an ICE AGE. There have been ice on the South Pole sometime from 14 million and 38 million years ago (NOTE the “accuracy” of guesses) which qualifies as being in one ice age.
The other ICE Age supposedly started about 1 million years ago (but only evidence shows around 750,000 years ago). And (recent discovery) that about 400,000 years ago the centre of Greenland had shrubs and grasses growing when the CO2 level was no higher (Vostok) than 300 p.p.m. – makes me wonder how much ice was there in the North Pole then.
And during the Eemian around 130,000 years ago the seas were 6-8 metres higher and lions, elephants, giraffes lived in the Thames Valley (with hippos in the water & the Rhine delta) from fossils. CO2 around 285 p.p.m. Agin I would wonder how much ice was at the North Pole.
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The social cost of carbon is extremely sensitive to the discount rate when borrowing money. A lower discount rate increases the SCC as this example shows:
“If the EPA uses a 2.5% discount rate, the SCC would be $120, but if it uses a 1.5% discount rate, the SCC would increase to $340. ”
The discount rate increased in 2022 and was at 4.5% at the end of last year. I suspect someone needed to find a way to drive the SCC iup in a high interest rate environment so manipulated crop yields to get there.
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You mean that climate alarmists lied? That’s probably only the tenth time it’s happened … this week.
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Trillions have been spent worldwide, but heck, who’s counting?
Given that much of the spending has added to debt, the return has been disappointing.
Electricity is now more expensive and less reliable and less stable in terms of voltage and frequency. There is massive environmental impact and human rights abuses in faraway places.
The gap between aspiration and achievement calls for investigation.
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The final solution to solar & wind fiasco..
Dump all subsidies & let the free market dictate the way forward.
Renewables will die a natural death without taxpayers having to pay the subsidies.
Our tax $$$ belong to Australian people not to half arsed politicians keen to shower foreign entities with our tax $$$ billions.
This applies to both parties!!
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Subsidies should have been dumped ten years ago, Graham. As we are reminded, subsidies were not required for T model Fords to take over from horses. Outboard motors soon replaced oars for getting your boat from here to there. Even traditional hunters have adopted Remington 243s over spears without subsidies. Their new found wealth for refusing to work does help but it is not a subsidy.
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These people are no better than fairground clairvoyants.
They should be treated with the same wariness and contempt.
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Is the Arctic rapidly warming?
An article in The Australian yesterday would have you believe so. So there would be a contest to see which nation(s) would win control of this area to gain access to resources exposed by melting ice cover.
I thought there was a long term cooling trend in southern Greenland so how could it be?
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The “media” always have to add in their salute to the great climate god, dont they? Pay respect to Greta. It happens so often and I think maybe that now Trump is calling out the whole scam, some in the leftist media will be adding these comments as needles. Yesterday I watched the ” Twister” doco on Netflix about the devastating tornado that hit Joplin, Missouri in May 2011. Right at the end there was the usual garbage acknowledgment to climate change, claiming that in a warmer world these events were more likely, blah, blah, blah. All nonsense of course, because there is no proof of that at all.
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There is no social cost of using “carbon” but a huge social cost of NOT using it.
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Now there’s a calculation that’d be worth doing.
What is the social cost of not using “Carbon”?
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It’s fantastic that atmospheric CO2 is naturally increasing but it’s still not high enough.
It got dangerously low, if it had gone below about 150-200ppm we could have suffered a mass extinction event.
I would like to see it at 800-1000ppm for optimal crop yields and a safety margin.
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Yep
The ‘optimal’ pre-industrial climate that greens want to return to was an era of massive crop failures and starvation with atmospheric CO2 at 280 PPM. It’s not called the ‘Little Ice Age’ for nothing. What moron decided that nightmare climate was optimal? They sure as heck didn’t ask me. I greatly prefer the warmer modern world I grew up in to the climate Hellscape that 17th and 18th century historians/authors described. And that was an Eden compared to the climate our stone age ancestors endured 10,000 years earlier, when atmospheric CO2 dipped to within a hair of sub-200 PPM level where photosynthesis stops and everything dies.
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Now, now, Steve,
What’s with this “Little Ice Age” bit?
Don’tcha know the correct usage is “before the Industrial Revolution”?
Cheers,
Dave B
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Every time a climate catastrophist announces another increase in CO2 – the greatest eeevvvaahhh – we should be rejoicing, not shutting down power stations, not that they have any significant affect on CO2 levels anyway.
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It will be very difficult to get atmospheric CO2 up to 800ppm, and even more difficult to keep it there, because we simply do not have enough fossil fuel. In a few hundred years it could be difficult keeping it above 400ppm, and in a few thousand years keeping it above 300ppm. At some time, I hope the world’s brains will start paying attention, and work out – for humanity’s survival – how to lift CO2 levels and keep them up. The only way I can see is nuclear fusion to break down limestone, but of course technological advance is difficult to predict, especially over hundreds of years.
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I am not suggesting CO2 could be raised with fossil fuel or other artificial means. It would be a natural variation so all we can do is hope for more.
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The everlasting phony climate change fiasco continues on and on. There seems to be no end to the scams, lies and deceptions associated with the whole scam. Not one article in the 100’s or even 1000’s of articles I have read since all this drama started last century has ever convinced me that CO2 is the problem. Greedy, controlling, power mad people are the real problem. As we all know , climate changes all the time, we have warming periods, little ice age etc. No one ever seems to take in to account the role and damage large volcanic eruptions cause. I keep a keen eye on the increasing volcanic activity of late with maybe 3 “super” volcanos stirring, Lake Taupo. Yellowstone and Campi Flegrei in the Bay of Naples. Climate Change people might actually have something to complain about if any or all of those erupt
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NZ’s White Island (who knew sulphuric volcanoes could be way-cyst) has been ‘more active than usual’ as of late, spewing forth large blocks of Vulcan Lego which have then rained down on the sea surrounding it, fisher-folk & divers beware!
On Tuesday a shallow 6.8 rocked the P.R.O.F. faultline halfway between Macquarie Island and our mainland, followed by a swarm of 4-point-somethings just offshore from me, ie. both ends of the Shaky Isles, so hopefully that’s released a little tension for the time being.
Meanwhile seismologists keep telling us the BIG ONE on the Alpine Fault is long overdue; and then there’s the Taupo Mega-Caldera still simmering away…
CO2? Pfft, a fart in a bottle a la Arrhenius.
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Lake Taupo is obviously in a caldera but it is a beautiful spot. I do hope it gives some warning before it pops.
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At last pushback on the climate scare is permitted . We have been living in an age when we have had the best time to be human (As Jo has pointed out), and a hard core of mostly geriatric power brokers has been sabotaging it . Climate insanity , disease insanity and now war insanity . Massive resources being diverted into wasteful and destructive ends . Hopefully this is the beginning of the new renaissance and rationality and accountability will return .
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The Thinking Community is fully aware of the climate scam but there is still no evidence of a change in Government policy in Australia or most Western countries, even after the exposure of huge “mistakes” such as Jo documented.
In Australia, the “opposition” “leader” even reaffirmed his commitment to the Paris Accords right after TRUMP abandoned them.
What exactly will it take to be rid of this insanity?
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Peter Dutton has to stop looking over his shoulder.
I think he can do it.
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CO2 emissions being bad for crops is something only an IYI (Intellectual Yet Idiot) could believe.
For the rest of us normies who have been to a greenhouse, or who learned in elementary school what vegetation looked like when dinosaurs walked the earth or learned the basics of photosynthesis in high school biology, we never lost a wink of sleep over the agricultural ‘cost of carbon’ because we knew it would be negative.
The atmospheric CO2 levels during the Mesozoic era (age of dinosaurs) was between 1000-2000 parts per million (2.5-5.0 times modern levels), and all those giant herbivores had to be eating something to maintain their colossal body mass. A 20 ton brontosaurus needs a ingest a lot of vegetation to get that big. Greenhouses/nurseries regularly pump in CO2 up to 1000 PPM in order to encourage plant growth, and the workers don’t require special gear to work in such conditions. The human body handles it just fine. And biology 101 tells us that CO2 is plant food and greatly enhances photosynthesis and reduces the water needed for plants to grow (which is why Sahara is slowly shrinking as the Sahel grows, because plants can grow in places now that they couldn’t 100 years ago thanks to CO2 fertilization).
Increasing CO2 levels harming crops has always been a preposterous notion. Not a farmer on earth ever believed such a thing. Only indoctrinated overeducated idiots who had never had soil under their fingernails did.
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And the late Jurassic had CO2 rising to about 2,700 p.p.m. as the temperature dropped slightly (to about 2℃ above current) and temperatures rose as CO2 reduced slightly.
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Not so sure of that Steve. I have heard a few farmers on various current affairs programs talking about “modifying their CO2 output” because of “climate change” and possible crop reductions. One wonders what kind of educational background such farmers have. But then, a lot of them seem to be supporting the payments they were going to receive from power companies wanting to put power lines through their properties.
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When it comes to the agricultural impact of carbon, I’ll trust a high school dropout farmer all day, every day over a guy/gal with multiple PHDs from an ‘elite’ university.
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Bumped for the quote
FWIW
“Not An Egg-spert, But-by Foxfier”
Read it all and you get to –
“This information is really easy to find.
If the folks you’re listening to didn’t find it, then please recognize they haven’t gone investigating, they are just theorizing without data.”
And I learned that a Guinea Fowl chick is a keet
https://accordingtohoyt.com/2025/03/24/not-an-egg-spert-but-by-foxfier/
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I’ve been listening to the “feed the world” BS narrative ever since becoming a professional agriculturist, way back in the mid 1980’s. It’s just as nutty as all the doomsday predictions of ag production from the climate mafia. Basically, the world is in a state of agricultural over production. Due mainly to improvements in management, tech, genetics, agronomy, animal husbandry etc over many decades, we’re actually over producing a lot of our basic food products. Also, countless field trials have shown only benefits to crop production under simulated increased CO2/ temp conditions. We need to anyway, because every year around 12m ha of prime agricultural land is lost to things like soil degradation and urbanisation. Gotta love Ross McKitrick- he’s about the only really famous climate scientist who actually lives up to his title. Most, like the IPCC, are just charlatans.
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Also, if you want to be real “sciency” have a look at this reference. There’s countless others, even Australian trials.
Roy, K.S., Bhattacharyya, P., Nayak, A.K., Sharma, S.G. and Uprety, D.C. 2015. Growth and nitrogen allocation of dry season tropical rice as a result of carbon dioxide fertilization and elevated night time temperature. Nutrient Cycling in Agroecosystems 103: 293-309.
Couple of quotes from the paper :-
“In discussing their findings, Roy et al. write that the aboveground plant biomass, root biomass, grain yield, leaf area index and net C assimilation rates of the plants growing under elevated CO2 conditions all showed significant increases (32, 26, 22, 21, and 37 percent, respectively) over their ambient counter-parts”.
“With respect to grain quality, the authors report there was no difference among the parameters they measured in any of treatments, with the exception of starch and amylose content, which were both significantly higher in the elevated CO2 and elevated CO2 plus elevated temperature treatments.”
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Not that there’s any assurances that the earth’s temperature will increase anyway. CO2 increase, probably yes, because it’s in a delay since the end of the LIA/onset of present warming period (1850->?). Nothing that WE do will affect the CO2 levels. Quite possible the world will start to cool off soon. Soon being decades long time frame. If you were a betting man (person?) 50/50 chance of either further warming/ cooling. Remember no-one can see into the future, not even Elon Musk.
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Nobody in the ‘apocalyptic food shortages’ camp saw Norman Borlaug coming. That guy should be a household name up there with the likes of Pasteur, Salk, Curie, etc. But the Club of Rome types despise him for demolishing their nonsensical Malthusian theories by revolutionizing agriculture.
One of my favories sci fi films of all-time is Soylent Green, but boy oh boy has the concept behind it aged badly, due in large part to Borlaug. Still a great flick, but the twin ideas of global food shortages and runaway population growth that underpin the story have largely been proven to be false. But there are still parts of it that have aged very well, such as the government run assisted suicide centers which have become reality in Canada and parts of Europe.
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Again there has been a massive decline in death rates from extreme weather disasters over the last 100 + years and over 6 billion MORE HUMANS at risk today than 1920.
Check out the data for yourselves and understand that very few people die today from extreme weather events.
In fact a 98% drop in death rates over that period of time. Why can’t these so called scientists find and then understand very simple graphs?
https://ourworldindata.org/grapher/death-rates-from-natural-disasters
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The Eemian ( 130 K to 115 K years BP) was 8 C warmer than our Holocene and SLs were 6 to 9 metres higher then than today in 2025.
Here’s the study from the Co2 Coalition Scientists and even Wiki quotes the same data.
So what’s wrong with their so called scientists and why can’t they find and tell the public the truth?
Co2 levels during the Eemian were about 280 ppm and about 424 ppm today in 2025.
https://co2coalition.org/facts/the-last-interglacial-was-8c-14f-warmer-than-today/
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The real social cost is the cost of a carbon tax .
The real environmental cost is the damage done by installation of wind and solar ” farms ” .
Further environmental damage is done by the mining and processing of minerals for the manufacture of wind and solar .
Further social cost is the cost of the ” transition ” to wind & solar .
Coal fired power stations do less social and environmental damage than wind & solar in every possible way .
There has been ENORMOUS social benefit from the cheep and reliable power delivered by coal fired power stations .
Further social cost will come from banning cars that work and replacing then with cars that are not fit for purpose ( and prone to self combust ) .
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Here’s the calories per person from 1961 to 2021.
I’ve listed all the continents and the World over that period of 60 years.
World population just 3.1 billion in 1961 and Africa just 291 million.
But by 2021 world pop about 8 billion and African pop about 1426 million or 1100 million MORE people in Africa by 2021.
World calories per person are 900 calories higher in 2021 and Africa are also much higher as well.
The extra co2 levels are certainly helping to feed 5 billion more people since 1961. See OWI Data link below.
We now know these are the highest calories per person in Human history, so what’s the problem with higher co2 levels?
Again, why can’t the so called scientists look up the data and think?
https://ourworldindata.org/grapher/daily-per-capita-caloric-supply?country=OWID_ASI~OWID_EUR~OWID_NAM~OWID_SAM~OWID_AFR~OWID_OCE~OWID_WRL~AUS
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Again, there has been a massive drop in death rates from fires and burns since 1980. Deaths per 100,000.
There has been a global fall of 220% since 1980 and a 600% fall in Aussie death rates per 100,000 since 1980.
In fact today Aussies now have the lowest death rates from fires and burns in the world. See OWI Data link below.
And billions more people at risk today.
https://ourworldindata.org/grapher/fire-death-rates?tab=chart&country=OWID_WRL~Low-income+countries~High-income+countries~Upper-middle-income+countries~Lower-middle-income+countries~AUS
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Here’s what the Co2 Coalition Scientists tell us about recent dangerous LOW LEVELs of co2 in our atmosphere.
“During each of the last four glacial advances, CO2 concentration fell below 190 ppm. At the end of the last glacial advance, it fell to 182 ppm, thought to be the lowest in the Earth’s history. Why is this alarming? Because below 150 ppm, most terrestrial plant life cannot exist”.
“We came within about 30 ppm (30 molecules out of every one million) to the extinction of most plant life on land, and with it the extinction of all higher terrestrial life-forms that depend on it. Bear in mind that, before we began adding CO2 to the atmosphere, we weren’t sure that we wouldn’t cross that critical 150-ppm threshold during the next glacial period”.
“Please note that many people confuse the glacial advance with “ice age.” The current ice age we are still in began about 2.4 million years ago. The planet altered between very cold periods known as glacials and warm periods called interglacials. We are thankfully in the tail end of interglacial warm trend”.
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Here’s the Co2 Scientist’s link to the past 4 full glaciations and the very dangerous LOW co2 levels.
https://co2coalition.org/facts/dangerously-low-co2-last-four-glacial-advances/#:~:text=During%20each%20of%20the%20last%20four%20glacial%20advances%2C,150%20ppm%2C%20most%20terrestrial%20plant%20life%20cannot%20exist.
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Great, in your face, opening by JoNova, and then, quality comments. The comprehension of what’s going on, per these topics, is almost too big to contemplate.
Yet sure is a refreshing atmosphere when i get a chance to visit.
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A hurricane went thru Florida, circa 1900, and then, in 2024, a same one did. What were the fatality figures, if they had much of so, but the populations of said tropical regions, was what?
500k compared to 10 million?
I don’t know how the native population did it, nor the Caribbean Islands for that matter, pre-the 1900’s where we acquired some forecast ability.
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Australia, at this rate is going to turn into a plantation, mixing rice with rabbit stew.
Al Gore and the club of Rome sure did get lost. And what’s his f?
Paul Ehrlich?
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Looking at the size of the error bars on the 2014 estimate, only soybeans were under threat from climate change anyway. Hardly worth spending trillions for that.
30
The movie Trading Places comes to my head.
(I think it’s the Sylvester tune from the party scene too: https://www.youtube.com/watch?v=hQ9lXRy7ys0&pp=ygUJc3lsdmVzdGVy – don’t keep try to tell me we are all transphobic!)
There must be some clever way we can short futures and bring them all down here.
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Paul Murray (SKY after dark) did a compare the pair – its a bonanza of facts – the taxpayer is Canberra’s slave as far Albo’s cheer mob is concerned and this comparison of now vs 20 years ago shows how badly the taxpayer is treated.
https://www.youtube.com/watch?v=qXQ8uBtm33Y
Population increased in 20 years 33%, tax take increased in 20 years (inf adj) – 96%. – yep the major part of Canberra’s tax is PAYE and the increase has been huge! Meanwhile Canberra’s spending has increased by 128% inflation adjusted. The comparison of public servants and departments shows the 420% fat cat swamp that is Canberra. the addition of states brings it to 555% cost increase over 20 years for 2.5 million public servants (masterful parasites).
It is ironic that this is the very reason Elon joined Trump to change the central government.
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Tricky things numbers. I read an article the other day casting doubt on world population estimates. It appears the powers that we have been greatly understating rural populations. So I guess for the alarmists, its worse than we thought!!
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EROI is another item to file under dubious green accounting practices.
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