"Importantly, if the world continues on the trajectory of decarbonization going forward that it has had since 1960, then we would reach net-zero carbon dioxide by around 2070, which is more or less consistent with a 2 degrees Celsius temperature target."

Sorry, but I don't understand this argument.

The "cabon intensity" is a fraction. It has become smaller since 1960, because GDP (in the denominator) has been growing faster than CO2-emissions (in the numerator). If this process goes on (which is plausible) the fraction will asymptotically approach the zero line around 2070. That's obvious. But relevant for global warming (according to the standard theory) are CO2-emissions and these will steadily grow until 2070, if the past trend holds on (which is plausible).

That means, we will not reach "net-zero carbon dioxide by around 2070" in absolute terms - only in terms relative to GDP. But to stop global warming we will need absolute net-zero carbon dioxide emissions - according to the standard theory.

I hope I am wrong, because that would be really great!

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To be fair, if we reach net zero by 2070 by continuing on with our progress over the last 6 decades, thats all wonderful, who could have an issue with that?

But of course that is not what we are doing, because CLIMATE EMERGENCY!!!!!!!!!!!!!!! so instead we are lighting our hair on fire and talking net zero by 2030/2035/2050 for absolutely no reason other that certain people want to get rich sooner.

There is no one with less credibility on climate than the UN head and yet all i see is statements from him all over the place.

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Dec 12, 2023·edited Dec 12, 2023

"then we would reach net-zero carbon dioxide by around 2070, which is more or less consistent with a 2 degrees Celsius temperature target."

Imaginary cause and effect, it comforts people to believe certain things.

I guess we'll actually find out in 2070.

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Be sure to see the addendum just added to this post

And here is the GDP time series (PPP) used by the GCP:


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Dec 9, 2023·edited Dec 9, 2023

I don't see how we get to net zero by 2070 or so based on the current trend, that means fossil fuels are out. How is that possible? Where is the energy going to come from? Nuclear is always out, and wind/solar can't do it all. Carbon capture doesn't seem at all feasible.

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Looking forward to your thoughts on the COP's long overdue wink & nod in a pro nuclear direction. I am skeptical that the now well subsidized weather restricted power mafia will let it happen. Too much for them to lose, by which I mean everything.

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Perhaps I overlooked something in your article but shouldn't the grams CO2 per US dollar be corrected for inflation? There are a lot more US dollars floating around these days and they buy a lot less.

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"the world’s economy has indeed become less carbon intensive by a great deal over the past 63 years. If that continues, we will indeed achieve net-zero carbon dioxide in the second half of this century." - Roger: please explain how that computes? The only way for emissions to drop while the world continues to use more energy is that decarbonization must increase faster than the rate of energy use. The integral of the difference must be great enough to reduce emissions toward zero in 2100. Looking at the curves, that seems impossible.

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Thanks for bringing visibility to this data, Roger. Even though it’s only adjacent to you climate expertise, it addresses the heart of energy policy.

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This is, as usual, an excellent post. Thank you. Much of the alarmist literature focuses on warming and global temperatures, and they argue for the immediate cessation of fossil fuel use. You have also spoken about the need to wean economy from fossil fuels. Mills, Bryce, Smil and others counter with the argument that the scale of such a program is beyond comprehension (my words).

That said, are you aware of any studies that show, conclusively, how what the global mean temperature if fossil fuels could be stopped tomorrow? Lomborg has argued that the IRA would reduce global temperatures by 0.028 degrees in 2100. I personally do not believe in absolute numbers, particularly when forecast 80 years from now, but Lomborg’s order of magnitude does suggest that “net-zero” (IRA’s goal) is of little value in reducing warming.

We are being asked to accept less reliable energy, at a greater level of economic discomfort, yet no one seems able to tell us even approximately what it will do. If it will make things less warmer, then by how much?

A second question: the world has warmed by 1.3 degrees over the past century. Alarmists tell us that 3 or more will bring global catastrophe. Therefore, there must be some point of inflection in the “good things” to “bad things” curve. Do you where that point is? Does anyone?

This might be a conversation best held over a bottle of good bourbon. Unfortunately, Substack has not yet acquired a liquor license.

Thank you in advance for thinking about this, and please keep up your good work.

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Decarbonization as defined by you is a nice quantity but it does not matter. What does matter is absolute value of emissions. So few can decarbonize til doomsday and still have a doomsday if emissions go up fast enough that as we continue to decarbonize, emissions remain high.

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Dec 8, 2023·edited Dec 12, 2023

"I won’t get into the details here, but the heavy lifting on accelerating decarbonization can only come from reducing the carbon intensity of energy."

The only realistic way to decrease "carbon intensity" is through the use of nuclear energy and possibly hydro power. Other "renewable" sources of energy acceptable today are wind and solar, which are exceedingly inefficient, wildly unpopular where they have been forced on a population , and they are utterly irrelevant in view of the determination of Third World countries to continue using fossil fuels. In fact the Third World's continuing use of FFs is the reason the world has continued to increase levels of CO2 in past decades (concomitant with gratifyingly greater prosperity) despite trillions of dollars spent by western nations on increasingly rejected and hated renewables. They cost too much, they don't work, and our economies are being hijacked by an ideology that is increasingly rejected by the people.

And what are our governments saying to this ? That we, western and prosperous powers , must keep going on this self-destructive transition to unreliable sources of energy because this is somehow going to set an example for the other nations. Well clearly It isn't working, because it doesn't work. Nobody in the Third World is serious about transitioning from FFs, and no one in America is serious about nuclear energy, the only realistic answer to both lower COP2 emissions and continued prosperity. To quote you (Roger Pielke Jr, ), "Whatever else global climate policy has achieved, it has not discernibly altered rates of decarbonization from the historical trend since 1960 — Remarkable!"

Another of your quotes is : "the world’s economy has indeed become less carbon intensive by a great deal over the past 63 years. If that continues, we will indeed achieve net-zero carbon dioxide in the second half of this century." How has this happened? Correct me if I am wrong, but mainly by using natural gas and other fossil fuels with lower emissions, and yet this has also been in lockstep with increasing CO2 emissions and without sacrificing our prosperity.. .Yet the global elites insist we must give up FFs if we are ever to achieve "Net Zero". Why is it that our progress is simply not good enough - because we still use FFs? And why should we accept "Net Zero" when our competitors do not?

It is a travesty that the progress made by the US in lowering CO2 emissions through the use of NatGas (which could also work in Europe) is not good enough in the eyes of the COP-whichever-number -- and perhaps in your eyes also - and is passed over as not good enough because the progress was made using a superior species of FFs. I guess I simply fail to see why you are so committed to Net Zero when it is so detrimental to our future and when it is clearly rejected by the poorest countries who will not sacrifice their futures to a Western ideology that cost too much and makes us poorer.

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what is the numerator in 2070?

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Dec 8, 2023·edited Dec 8, 2023

" Continued efforts to improve efficiency ".

I would dispute that. The political efforts to reduce energy efficiency have increased to an extraordinary level the past decade or so. All such energy scams like Wind, Solar, Hydrogen, Utility Battery Storage, Biomass burning for electricity, Agrofuels, ITER, CCS, Tidal, Wave, Deep Geothermal are all the paragon of Energy Inefficiency. Electrification of Transport has some potential for improving efficiency, but that potential is overwhelmingly in the area of heavy trucking, ferries, buses, LRTs, Rail, short distance shipping, not for Light Vehicles. And for nuclear long distance shipping, which is being boycotted by our illustrious hypocritical leaders. The opposite of what needs to be done is being done.

To maximize Energy Efficiency, the best path forward is obvious replacing fossil with EROI typically ~30:1 with Nuclear, basic PWR tech is 75:1, CANDU's upwards of 120:1, GenIV LSFRs & MSRs upwards of 300:1, some estimates at 2000:1 for MSRs. Certainly you don't want to use Wind & Solar with EROI of <16:1, including buffering <3:1. Or corn ethanol ~1:1 (which Biden is increasing).

Also the drastic efforts to reduce Agricultural Productivity, mostly by restricting fertilizers, but land reforms also, are despicable ways to further reduce Energy efficiency.

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