CSS-71 – IPCC Model/Theory Shortcomings – Revisited

CSS-71 – Revisited My posts can be quite detailed. My apologies, but that detail is required. “Climate Change” is complicated, irrespective of the simplistic, unscientific All CO₂, All the Time alarmist narrative pushed by the UN/WEF/IPCC, etc. and their political/academic/media, etc. minions. This post will distill the IPCC’s Model-Theory Shortcomings down to a few charts and highlight the simplistic/complicated differences.

For those that prefer the quick look, summaries are available in the two PDFs listed here (2 Page Summary – Short and 2 Page Summary – More Detail).

#climatechange #delaythegreen #globalwarming #showusthedata

The starting point is the IPCC’s “best estimates” computer model history match (shown above). There are three matches shown here. The Total Radiative Forcings (RF, the blue curve), The Total Anthropogenic RF (the black curve) and the CO₂ RF (on its own, the gold curve). Note the volcanic RF was removed to simplify the chart. The first thing you should notice is that Total RF and the Total Anthropogenic RF history matches are almost identical. The models are intentionally programmed to ignore natural forcings. The IPCC’s Solar RF is limited to just one of the 40+ Total Solar Irradiance (TSI) reconstructions available and totally ignores the many other more powerful Solar RFs (Cosmic Ray Flux (CRF), High Energy Particles (HEP), Solar Wind/Electromagnetic Field Strength, etc.). They also do not include the many ocean cycles that have global impacts. The Atlantic Multidecadal Oscillation (AMO) is easily visible in the HadCRUT5 surface temperatures (despite the over-homogenization). As are the strong El Niño Southern Oscillation (ENSO) pulses in 2015 and 2023/24. Most of the post-2014 temperature increases are ocean related (an indirect solar forcing), not CO₂. The CO₂ forcing curve does correlate well with the HadCRUT5 surface temperature estimates, hence the All CO₂, All the Time alarmist narrative.

Unfortunately for the alarmist community, correlation does not equate to causation. You must look at much longer data sets to establish causation. The Modern Temperature Record (MTR, 1850 to 2025, 175 years) is not a statistically significant dataset in a ‘climate change’ discussion. It equates to less than 6 effective data points based on 30-year averages. Given that ‘climate change’ occurs over decades/centuries/millennia, the Holocene provides a much more representative look at ‘climate change’. We can start by extending the IPCC’s CO₂ correlation (shown previously), back in time over the Holocene (shown below, Figure 2).

Obviously, CO₂ and any other anthropogenic forcings will have little to no impact on climate prior to the MTR. So, was the climate stable and/or unchanging over the pre-MTR Holocene? Absolutely not! The climate (temperature, sea levels, glacier advances/retreats, etc.) was in constant flux as shown below (Figure 3). Somehow the climate was changing (dramatically and in both hemispheres) without any help from CO₂ (the IPCC’s primary answer to ‘climate change’). Those natural forcings (primarily solar through both direct and indirect means) were still active during the MTR and will still be active in the future (just not in the IPCC’s models that have been self-acknowledged to run too hot and use unrealistically high emission scenarios (i.e.: any scenario above ssp2-4.5)).

The IPCC alarmist narrative implies that the MTR warming (1.07 °C according to the IPCC’s August 2021 AR6 report) is due almost exclusively to anthropogenic forcings (primarily CO₂). But is that true? As mentioned earlier, there are 40+ TSI reconstructions available. Many of these reconstructions can be used to model the MTR directly and virtually all of them produce a better history match if used as a proxy (i.e.: to compensate for the IPCC ignoring the many other solar forcings (CRF, HEP, etc. discussed earlier)). That includes the IPCC’s singular Matthes et al 2017 choice.

To highlight this point, the history match below (Figure 4) was produced by starting with the IPCC’s “best estimates”, adding in the Atlantic Multidecadal Oscillation (AMO) and swapping out the IPCC’s Matthes et al 2017 TSI PMOD extended reconstruction with an alternative option. The alternative used here is an average of 6 ACRIM extended TSI reconstructions. The PMOD and ACRIM extended methodologies are discussed in the original post (CSS-71 – IPCC Model/Theory Shortcomings).

The end result, a natural forcing weighted history match is far superior to the simplistic, unscientific anthropogenic forcing version that we started with. Is this history match all encompassing? No, there are many other forcings that could be added in. An obvious one being the ENSO influences readily visible in the post-2014 HadCRUT4 surface temperature data. This history match sets CO₂’s Equilibrium Climate Sensitivity (ECS) at 0.8 °C. Is that the correct value of CO₂’s ECS? Hard to say, given that CO₂’s ECS is nowhere near settled science. But 0.8 °C is a relatively reasonable estimate of the ECS when the discussion is limited to just the radiative forcing on its own (as laid out in my OPS-80 – CO₂ Affects Temperature but Does CO₂ Drive Climate and CSS-69 – CO₂’s Cooling Parameters posts).

I suspect the alarmists’ primary argument against using the solar forcings is that there are no definitive mechanisms to explain how solar activity is driving the climate. That is not true. For example, there is evidence that Cosmic Ray Flux affects the climate by moderating cloud cover albedo (a very important but poorly understood climate parameter). To be fair, the current understanding of the CRF mechanism does not explain all the cloud influence but is that any different than the IPCC’s proposed positive water vapour feedback mechanism that surmises a CO₂ warming increase leads to additional evaporation, which leads to higher atmospheric water concentrations which leads to warmer temperatures, and so on and so on.

The IPCC has put forward a mechanism, but that mechanism is obviously unsubstantiated given that they are still using a wide range of CO₂ ECS (1.8 to 5.7 °C). And their low end ECS is obviously too high given that their models run too hot and use unrealistically high emission scenarios. The models are also ignoring CO₂’s cooling parameters (CSS-69, increasing leaf cover and co-aerosol production). These cooling parameters may already be dominating CO₂’s radiative forcing warming, leaving the IPCC’s positive water vapour feedback mechanism meaningless.

The IPCC has chosen a very simplistic and unscientific approach to ‘climate change’. They can certainly choose to stick with their “best estimates”, but a proper scientific approach would also recognize that there are other reasonable (actually better) alternatives. It is way past time to put Net Zero, the Energy Transition, etc. in the rear view mirror and start addressing the real and actually dangerous problems we are facing, right here within Canada. Sadly, under our current UN/WEF leadership, that future is likely not in the cards.

For more perspective and more detailed analysis, you can also check out some of the following posts.

IPCC Model/Theory Shortcomings – 2 Page Summary – Short

https://climatechangeandmusic.com/wp-admin/upload.php?item=4366

IPCC Model/Theory Shortcomings – 2 Page Summary – More Detail

https://climatechangeandmusic.com/wp-admin/upload.php?item=4365

IPCC Working Group 1 (WG1) Sixth Assessment Report (AR6) Annex III Extended Data

https://zenodo.org/records/5705391

IPCC Working Group 1 (WG1) Sixth Assessment Report (AR6) Annex III Extended Data

https://zenodo.org/records/5705391

Open Letter – Addendum

Addendum

Challenges in the Detection and Attribution of Northern Hemisphere Surface Temperature Trends Since 1850 – Connolly, Soon et al 2023

https://www.researchgate.net/publication/373205213_Challenges_in_the_detection_and_attribution_of_Northern_Hemispheresurface_temperature_trends_since_1850

https://iopscience.iop.org/article/10.1088/1674-4527/acf18e

The Detection and Attribution of Northern Hemisphere Land Surface Warming (1850–2018) in Terms of Human and Natural Factors: Challenges of Inadequate Data – Soon, Connolly² et al 2023

https://www.mdpi.com/2225-1154/11/9/179

Center for Environmental Research and Earth Sciences (CERES)

https://www.ceres-science.com

ACRIM Gap Discussion

(PDF) Comparison of ACRIM and PMOD Total Solar Irradiance composites time series during solar cycles 21 – 23

https://www.researchgate.net/publication/270274810_Comparison_of_ACRIM_and_PMOD_Total_Solar_Irradiance_composites_time_series_during_solar_cycles_21_-_23

Climate Short Story (CSS)

CSS-29 – Climate Model – TSI-AMO-CO₂

Climate Model – TSI-AMO-CO2

CSS-52 – Extreme Weather Events

Extreme Weather Events

CSS-37 – Hurricanes – Accumulated Cyclone Energy (ACE)

Hurricanes – Accumulated Cyclone Energy (ACE)

CSS-69 – CO₂’s Cooling Parameters

CO2’s Cooling Parameters

CSS-71 – IPCC Model-Theory Shortcomings

IPCC Model/Theory Shortcomings

One Page Summary (OPS)

OPS-8 – Basic Climate Model

Basic Climate Model

OPS-56 – The Holocene & Solar Activity

The Holocene & Solar Activity

OPS-80 – CO₂ Affects Temperature but Does CO₂ Drive Climate?

CO2 Affects Temperature but Does CO2 Drive Climate?