To make predictions on a non-linear, chaotic system for years 100 to 300 years hence takes, how shall I say this, a certain lack of humility. Hubris. That's the word I was looking for. Hubris.

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Thank you for this insight into the world of climate policy sausage making. The unquestioned acceptance of a significant set of assumptions is fantastic. The choice to stay with an extreme anti-scientific projection says a lot. The instructions to us civilians, who have 0 influence on climate policy, irt our ignorance of net 0 is fascinating. Especially when compared to the near complete lack of understanding the political "leaders" on climate demonstrate daily. The lack of critique of the political/big green policy maker's understanding of net 0, energy, data, etc. is even more instructional.

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One very important distinction to keep in mind is that there are two "Net Zeros". There is the scientific definition whereby human GHG contributions - human GHG removals are equal to zero. That is not the Net Zero that is being promoted. What is being promoted is the Carbon Trading Scam called "Net Zero". That is just a devious effort to make giant government guaranteed profits for the uber-wealthy investors, to unscrupulous corporations to greenwash their emissions and virtue signalling for the ultra-rich, while facilitating massive wealth transfer from the Western Middle Class to the Ruling Class Elites. Kleptocracy at its finest. A couple good examples:

And all these companies like Apple that buy wind & solar RECs so they can falsely claim they are "carbon neutral". Sorry, but that's not how the electrical grid works. They are consuming avg grid mix same as every other electricity consumer.

And all their wind & solar does is reduce the efficiency of the electrical grid, which means they don't reduce emissions. In fact, they drastically INCREASE emissions, when you consider their very high opportunity cost.

And consume ~50X the raw materials that Nuclear does for the same amount of energy. I guess Mother Nature doesn't care because most of that is in China. With an overall EROI that is so low that they are a physically impossible replacement for fossil fuel.

You need only compare the emissions reductions failure that is Germany with the emissions reductions success that is France, France with 10X lower GHG emissions per kwh of electricity than Germany. Much lower than that in materials consumed and waste generated. France partially reprocesses their Spent Nuclear Fuel so they only consume 5oz of uranium per person per year for 88% of their domestic electrify supply. About $15 per person per year. While Germany consumed over 80M tonnes of Coal in 2022. About 2200lbs per person for 31% of their electricity production. Equivalent to 5500lbs/person compared to France @ 78% of their electricity production.

As for Apple's forest carbon offsets claims. Read this & weep, Tim Cook:

The Biggest Green SCAM In ESG | Breaking Points, Krystal breaks down the corporate scam of ESG and carbon offset programs in the USA:


Revealed: more than 90% of rainforest carbon offsets by biggest certifier are worthless, analysis shows:



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It is with a feeling of irony that I read this just after reading the Risk Monger’s latest. There seems more than a bit of “scientism” here. Figuring out whether we CAN reach Paris’ artificial target is less important than answering whether we SHOULD. And climate modeling - in whichever direction- can’t answer that.

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If Paris targets can't be achieved, they won't be. And they can't be w/o China, Russia, India, etc full participation. Adaptation is the only reasonable road.

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All of this presumes that anthropogenic GHG are the control knob of climate. To which I ask, what part of Wijngaarden & Happer, 2020 do you disagree with? The curtailment of anthropogenic CO2 is causing great harm to the poor; the rise in atmospheric CO2 and modest temperature is highly beneficial to the biosphere and hence humanity, while the imposition of weather-dependent and low energy dense wind and solar and EVs only benefit the vested interests.

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Thanks for enlarging the scope of the discussion, Roger. Wallace Stevens is right: There are “Thirteen Ways of Looking at a Blackbird.”

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If the goal is to use inverse modelling to assess emissions that meet or get close to Paris targets of 1.5 or 2.0 C, then the choice of value(s) for climate sensitivity must reflect the range of uncertainties associated with climate sensitivity. It would seem that to be reasonably confident of meeting the Paris targets one is compelled to invoke the maximum plausible value for climate sensitivity in the inversion calculations. This might mean including the recently disparaged RCP8.5. Otherwise, its plausible that the goal might not be achieved. How do you deal with these uncertainties in your inverse modelling?

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The graphs look great, but how realistic are the projections? If atmospheric carbon dioxide exceeds 450 ppm by 2050 (likely!), we won't make Paris.

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Oct 30Liked by Roger Pielke Jr.

"The results depend on the value chosen for climate sensitivity..." What value is assumed in creating these charts?

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I appreciate the message in this post, but

Leaving all that aside, recently the alarmist/activist crowd has started shifting the conversation to the next goal, zero combustion.

So forget emissions levels, net zero etc now zero combustion is the coming thing.

As with how these things work we will see more and more “peer reviewed science” that will take this up and then the alarmists will use this “science” to push ever more ludicrous policy that captured governments will try to enact.

An ever widening catastrophe.

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I have heard it said that the forests in Canada absorb much more CO2 than we emit from human causes. Does that mean that Canada is already below net zero?

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All of these studies assume the truth of the hypothesis That more CO2 will absorb more of earth's radiation.

In 30 years of belief, no one has ever shown a proof of this hypothesis. Could it be that the hypothesis is not true?

NASA performed a study in 1991 on the atmospheric transmission/absorption of earth's radiation. It revealed that, in the only wavelength band that CO2 effectively affects, 14-16 microns, the present atmosphere already absorbs ALL the energy, none gets to space. So more CO2 can have no effect.

This study (NASA Technical Memorandum 103957, Lord 1992) lay hidden for 30 years and is only now publicly available. Also now to be found on Kindle.

During this period, it was made available to the infra-red astronomy NASA program Gemini. Its successful use here for decades has proven its reliability.

This disqualifies all the models and predictions to-date.

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Oct 30·edited Oct 30

While I found the post valuable for the non-expert, I think the information in the following para could have been a bit more complete: "The CO2 budget that determines future CO2 concentrations is the sum of sources — anthropogenic emissions and positive feedbacks — offset by sinks of CO2 into the ocean and terrestrial biosphere". As you know well, while the ocean sink is considered fully natural, the terrestrial biosphere's sink is partly natural and partly anthropogenic. In the 2nd half of the century, models assume that the natural terrestrial sink will essentially disappear (or even turn into a source), while they rely on the build-up of anthropogenic terrestrial sinks to offset any remaining (hard-to-abate) fossil emissions. Therefore, to complement your post, I think it's useful to remind to all that 'net-zero' refers to 'anthropogenic emissions + sinks' (i.e. not only emissions).

Closely linked to this is how to define 'anthropogenic sink'. As you know, this is my area of expertise. For any reader interested to know more, I suggest the following papers, which explore the different approaches used by global models (and IPCC AR6) and national GHG inventories in defining what anthropogenic sinks are:

- https://www.nature.com/articles/s41558-021-01033-6.pdf (a summary is here: https://www.carbonbrief.org/guest-post-a-rosetta-stone-for-bringing-land-mitigation-pathways-into-line/)

- https://essd.copernicus.org/articles/15/1093/2023/

Another paper on this issue will come out in a few weeks in a top-level journal.

The implications of different definitions of 'anthropogenic sink' are huge, as they may jeopardise an accurate assessment of the collective climate progress, equity of efforts among countries, and confidence in land use GHG estimates.

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Informed energy policy decision making requires something more important than climate change modelling. More important are study and analysis of the cost/benefit ratio of implementing Article 2 of the Paris Agreement, and fair representation of both the benefits and detriments of global warming. Climate science and energy policy have become the handmaiden of political narratives and inadequately examined aspirational goals, and are, in a word- surreal.

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