“All in all, and contra to the IPCC reports, there is insufficient evidential basis for the use of carbon dioxide, et cetera, emissions – taken together, the IPCC’s Anthro – as climate policy variables.” − Green and Soon, 2025
A new evidence-based study provides compelling evidence that for decades the IPCC has been engaged “advocacy research,” or the “antiscientific practice of undertaking research designed to support a given hypothesis.”
The IPCC-favored climate model parameters used to support the narrative that climate change is primarily caused by humans burning fossil fuels (referred to as the Anthro models in the study) is so fraught with errors that even a stripped-down benchmark model that merely projects future temperatures will not deviate from the historical average overwhelmingly outperforms the IPCC’s modeling.
“The IPCC’s models of anthropogenic climate change lack predictive validity. The IPCC models’ forecast errors were greater for most estimation samples – often many times greater – than those from a benchmark model that simply predicts that future years’ temperatures will be the same as the historical median.”
The IPCC’s Anthro models that hypothesize CO2 (primarily) will foment dangerous global warming over the coming decades woefully overestimated the warming from 1970-2019 by anywhere from 1.8°C to 2.5°C.
“The errors of forecasts from the anthropogenic models for the era of concern over manmade global warming, starting in 1970, were 1.8°C (AVL), 1.7°C (AVSL), 2.3°C (AVR), and 2.5°C (AVSR) warmer than the measured temperatures.”
Over the 2000 to 2019 period the Anthro models’ forecast errors were a staggering 16 times greater than the simple benchmark model’s errors.
“…forecasts for the years 2000 to 2019 from models estimated with 50 observations of historical data (1850 to 1899) have MdAEs [median absolute errors] of around 17°C or 1600 percent greater than the 1°C MdAE of forecasts from the naïve benchmark model.”
In contrast, the authors found the models that centered on Total Solar Irradiance (TSI) as a climate change factor did indeed have predictive validity, and their error ranges were much smaller.
Considering the magnitude of the error in using CO2 emissions as a basis for climate forecasts, the authors conclude the Anthro models’ unreliability “would appear to void policy relevance.”
Image Source: Green and Soon, 2025
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
I think it would be interesting if some of the climate models could be run with the carbon dioxide emissions effect as zero.
That’s why the Russian model is closest to reality – because it has the smallest assumed CO2 “effect.”
An important proof against the CO2 global warming claim was included in John Christy’s testimony 29 March 2017 at the House Committee on Science, Space and Technology. The text and diagram below are from that document which can be accessed here.
IPCC Assessment Reports show that the IPCC climate models performed best versus observations when they did not include extra GHGs and this result can be demonstrated with a statistical model as well.
“The IPCC inadvertently provided information that supports this conclusion by (a) showing
that the tropical trends of climate models with extra greenhouse gases failed to match
actual trends and (b) showing that climate models without extra greenhouse gases agreed
with actual trends. A report of which I was a co-author demonstrates that a statistical
model that uses only natural influences on the climate also explains the variations and
trends since 1979 without the need of extra greenhouse gases.”
Christy’s testimony is Here:
https://science.house.gov/_cache/files/5/6/56b2c90e-acc2-4cab-bb10-a510d3cb43ac/AD54FE912F5E3094C8B391DA314D1E4C.hhrg-115-sy-wstate-jchristy-20170329.pdf
That’s called a baseline run. Without a CO₂ change, air temperature jitters around the zero line, no matter how large the number of projection years.
“I think it would be interesting if some of the climate models could be run with the carbon dioxide emissions effect as zero.”
Unfortunately, running a zero in coded mathematical functions often has a very bad result on all of the calculations.
Temperature x 0 = 0. Which will propagate as 0.
Without massive “errors” (and massive propaganda )the climate crisis would not and could not exist.
But crisis’ are essential to shift power towards the UN(and WHO as result of the other crisis that made the flu disappear in 2021 ).
And people with globalist ambitions will get all the crisis they need to reach their goals.
Coincidence is always on their side.
The greatest way to influence public opinion is fear.
I thought it was just starting every announcement with “scientists say . .. .. “
and including “good paying union jobs” and ending with “our most vulnerable.”
The headlines are the fear. The rest is the logic fallacy of appeal to authority with the emotional grabbing ending.
And a healthy dose of ‘could possibly’ and ‘predicted to be’….
We have known this for years and years. Willis has made the point in a recent essay that ECS has a continually larger range over the the past 50 years of research and probably trillions in taxpayer’s dollars.
Dr. Pat Frank has shown that the models revert to simple linear projections and have an uncertainty that subsumes any projected value. As shown in this study a simple model performs better.
One would think after one-half century, the modelers would have a serious reflection on their inability to make reasonable projections. Instead they simply retrench and keep on keeping on.
If they admit their models are wrong or have big problems they would be out of a job. So instead the scam continues.
This would require climatologists learning the basics of metrology, especially how measurement uncertainty always accumulates. Judging from the history of the subset that posts to WUWT, this isn’t going to happen anytime soon.
Before they can improve their modes, they’d have to give up on some assumptions around which their professional lives exist.
It would be a pleasant surprise if the modelers incorporated basic electro magnetic fields and waves.
One would think that modelers would have taken Edward Lorenz at his word. Apparently, when research dollars are dumped endlessly into folly, programmers are delighted to engage in that folly.
It takes the saying “learn to code” to a whole new level.
I still find it beyond comprehension that someone can model molecular level interactions with a 25 km grid model.
Although Trump has forced him to take cover, Chicken Little is alive and well in European
Union and Brexit UK Net zero circles, just waiting for the next big hurricane to scare us back into submission.
Climate alarmism is inevitable once one assumes that Schwarzschild’s model of radiant transfer applies to IR-active gases in the lower troposphere.
However, this is likely a specious assumption given that the thermalization of excited GHG molecules by collisions with non-GHG species near the Earth’s surface prevents the spontaneous emission of photons required for radiant transfer models to be valid.
Someone pleasingly knows the definition of thermalize.
This video highlights these issues. The problem with CO2 and Temp models is that they are linear. Backradiation shows a log decay. The climate scientists don’t even know the basics of modeling 101. This video shows the models and how bad they are.
https://app.screencast.com/ZMpNTvkLD7DDJ
This video shows why CO2 won’t cause warming in a very funny manner.
https://app.screencast.com/DFd1viHxsRjq7
So let’s summarize.
The models are garbage.
+10
Some people put too much faith into computer models.
Some people put all of their faith into computer models.
Wait. The models have no equations for faith. The assumptions, yes.
Continuing, so the original statement stands verified.
Admitting that you were wrong is a very hard thing to do; made harder when the hand that feeds you needs you to be right to save their own hides.
Need you to be right. Not quite. Need you to say they are right is more accurate.
They don’t need to admit they’re wrong, that’s been proven by multiple lines of evidence – including the study cited in this post. What’s needed is a complete cessation of funding. It is insanity to keep buying a product that has been proven to be useless.
Back in the early days of the CAGW scare, it must have been tough for them to make their predictions.
I mean, they had to pick a time frame soon enough to cause panic and policy changes to prevent it yet far enough out for the policy changes to be enacted before the “forecasting” could be shown to be false.
(See the “PREDICTIONS” drop down on the title bar.) 😎
Most reflect a running 5 year cycle.
After 50 years of nothing much happening, more climate models are not needed. What is needed is commonsense at all levels of government. Ordinary people are already clear about climate. The climate is working just fine. It is the elite morons whose deep anxieties and rent-seeking goals who keep this fiction alive.
New Analysis: IPCC’s Emissions-Based Climate Model Errors So Massive They Eliminate Predictive Validity
Widely known since 2019.
The IPCC is made up of politicians, and is a fraudulent organisation.