You just made a long series of claims there, but I don't see any reference to associated literature. They mostly seem inaccurate or a gross simplification of positive feedbacks like albedo -- and ignore CH4 (and CH4 hydrate feedbacks) as well as the various halo-carbons and short-lived aerosols -- at least from what I remember from climate science courses I've taken. Would you mind linking something peer-reviewed that I can read? It's certainly possible that you've just outsmarted 10,000 actively-publishing PhDs, but seems relatively unlikely just as a matter of statistical odds, no?
You’re arguing from various angles there, all politically advocacy based, beside the point, & the last sentence especially, totally imaginary.
It’s quite simple.
The IPCCs estimate for equilibrium climate sensitivity, as deduced from climate models, is based on an increase in radiative forcing of 3.7W/m2. This is equal to, & based on a doubling of CO2, because no matter what the atmospheric content of CO2 happens to be, doubling it only ever results in an increase in radiative forcing of 3.7 W/m2, due to the diminishing effect of CO2 as it increases in the atmosphere. This is just basic knowledge, as stated in the wiki link I provided, quote “a doubling of CO2 (which amounts to a forcing of 3.7 W/m2), end quote.
It is also basic knowledge that the range of model projections for a doubling of CO2 is based on the direct increase in forcing from CO2, plus hypothesised positive & negative feedbacks.
The direct effect of doubling CO2 is just 1°C. Again to quote wiki “CO2 climate sensitivity has a component directly due to radiative forcing by CO2, and a further contribution arising from climate feedbacks, both positive and negative. "Without any feedbacks, a doubling of CO2 (which amounts to a forcing of 3.7 W/m2) would result in 1°C global warming, which is easy to calculate and is undisputed. end quote
And from the IPCC, quote “In the idealised situation that the climate response to a doubling of atmospheric CO2 consisted of a uniform temperature change only, with no feedbacks operating, the global warming from GCMs would be around 1.2°C (Hansen et al., 1984; Bony et al., 2006).” End quote.
Now the IPCC’s estimate for an increase in global average temperature, based on climate model projections for an increase in radiative forcing of 3.7 W/m2 (2 x CO2) is 1.5°C to 4.5°C.
The reason for the significant disagreement between the individual model projections (model spread, of 1.5°C to 4.5 °C) is the same reason for why they all project more warming, & not less warming, than for the direct effect of CO2,,,, because they all hypothesise >>>net positive feedback!
Net positive feedback is based on the hypothesis that hypothesised positive feedbacks, primarily water vapour & cloud feedback, not only dominate negative feedbacks, but, quote IPCC “multiple positive feedbacks mutually amplify each other’s impact on climate sensitivity” end quote.
If in reality (not IPCC climate models) feedback was net negative, equilibrium climate sensitivity would be less than the direct effect of CO2.
IPCC 8.6.2.3 What Explains the Current Spread in Models’ Climate Sensitivity Estimates?
The IPCC states “In AOGCMs (climate models), the (positive) water vapour feedback constitutes by far the strongest feedback”
And
“Because the water vapour and temperature responses are tightly coupled in the troposphere, models with a larger (negative) lapse rate feedback also have a larger (positive) water vapour feedback”
“The (positive) water vapour feedback, operating alone on top of (the direct effect of CO2), would
at least double the response”
So, no doubt that the hypothesised positive water vapour feedback in the IPCC models is not only adding a lot more warming to the model projections, but is partly to blame for the “spread” of estimates depending on its computed strength.
As I said in a previous post, the data has disproved the hypothesis of positive water vapour feedback.
The hypothesis says clearly & simply that the rate of warming in the tropical mid/upper troposphere will be significantly faster than the rate of warming in the atmosphere below, down to the surface. Radiosondes & both satellite data sets show the opposite to be true – reduced humidity at that altitude, & a faster rate of warming at the surface than the mid troposphere – the opposite of the models, & in fact, indicating negative water vapour feedback.
Back to the IPCC: “(Positive Cloud feedback) amplifies the basic response (CO2) by 10 to 50%
depending on the GCM.”
So the IPCC models say that the (disproved) positive water vapour feedback, & the hypothesised positive cloud feedback, which are responsible for a reduction in the albedo effect, will be even worse than their individual contributions because the IPCC models again hypothesis ““multiple positive feedbacks mutually amplify each other’s impact on climate sensitivity”
So hypothesised cloud feedback says that total cloud cover will reduce due to warming (even though evaporation will increase), and allow more shortwave radiation (sun light) to reach the Earth’s surface, warming it more, increasing longwave radiation to the atmosphere to be intercepted by greenhouse gasses?
I learnt that the precipitation cycle works like this: - evaporation of water into the sky, forms clouds, rains. Not only are we expected to believe that more evaporation won’t result in an increase in clouds, but a decrease in clouds. Some models do have negative cloud feedback (an increase in total cloud cover) & they’re the only half decent models.
So, the models not only disagree with each other on the strength of water vapour feedback, the data proves they got the response wrong (negative feedback not positive) They also, not only disagree on the strength of cloud feedback, but disagree on whether it’s positive or negative.
It cannot be proven that any warming occurring in the last 300 years or so, or even recent warming, can be attributed to increased greenhouse gasses. Some of the warming probably is, but it cannot be proven that it is anything other than natural variability. One can suggest that is attributable to co2, because it has increased. But correlation does not prove causation, & there are too many other factors & unknowns & uncertainties involved. But, even if all the (assumed) recent warming was attributed to the increase in atmospheric greenhouse gasses that has occurred, all that would show is, that, the climate is not as sensitive to those gasses as the models project.