how stupid can denial get?

Originally posted by szaba_the_hut ↑

1a. My view is that recent interglacials have lasted from 10,000 to 30,000 years and moving forward now beyond 12,000 years of interglacial the ice age natural forcing/s is/are probably going to re-occur any time from now to 18000 years from now. It then comes down to a question - is the antropogenic CO2 forcing exceeding the natural forcing/s that cause ice ages?

OK - what is the Anthropogenic CO2 forcing (climate sensitivity)? AR5 consider it is most likely something between 1.5 to 4 degrees C (most likely but not certain) per doubling of CO2. We havent been able to rule out that climate sensitivity is < 1 degrees C per doubling of CO2 (or > 6 degrees C). On that basis we simply do not know if an ice age can be averted by current anhthropogenic CO2 emissions. I have said numerous times that it would be nice if climate sensitivity is sufficient to avert the next ice age but we just do not know if that is possible because we do not know what the climate sensitivity to CO2 concentration exactly is at this time.

1b. noted
1c. See AR5 climate sensitivity estimate range. We can say what it might do under certain assumptions but knowing the wide range of possibilities for CO2 sensitivity many other scenarios are equally as likely including a change from warming to persistent cooling due to ice age transition natural forcing exceeding CO2 forcing.

1d. Models are poor at predcting the future if they require us to assume future variable values when projecting forward - most humans tend to choose values that suit our opinion view/future income stream. If variables are not well understood (like climate sensitivity to CO2) then such a wide range of scenarios is possible that the value of the model as a predictive tool becomes dubious because all future states are predicted from less than 1 degree warming to 6+ with steady state natural forcings!

1e. Previous ice ages were around -12 degrees anomaly to current temp. If anthropogenic CO2 continues at 3PPM per annum (unlikely) it will take 130 years to do the next doubling and hydrocarbon resources will either be mostly exhausted (oil and gas) or replaced (coal) - even at the upper-most end of the likely sensitivity that is +4 degrees C anomaly in 130 years we then have 4870 years of carbon sink response to get to 5000 years. If a -12 degrees anomaly force kicks over the subsequent 5000 years then with 10,000 years of natural carbon sink activity available to reduce concentration and temperature before it does serious battle with 90,000 years of ice age......what will happen? At the bottom end of the likely CO2 sensitivity it is only +1.5 degrees C. Is that enough?

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OK, I'm not going to waste much time on this.

On your first point.
"
OK - what is the Anthropogenic CO2 forcing (climate sensitivity)? AR5 consider it is most likely something between 1.5 to 4 degrees C (most likely but not certain) per doubling of CO2. We havent been able to rule out that climate sensitivity is < 1 degrees C per doubling of CO2 (or > 6 degrees C). On that basis we simply do not know if an ice age can be averted by current anhthropogenic CO2 emissions.
"

As I've hinted at already, climate sensitivity isn't relevant here. Climate sensitivity gives us the equilibrium temperature after warming has been initiated by CO2 gasses, when also accounting for earth feedback processes over time.

Equilibrium outcomes are not relevant when you are determining if there is any net forcing to even initiate a change.

The question is, solely, do insolation changes due to orbital variation reduce radiative forcing by enough to offset the (measured) radiative forcing change of greenhouse gasses. Hence is there ANY net cooling effect from the sum of Milankovitch impacts and CO2 impacts.

The answer is there's no net cooling forcing. Measured CO2 radiative forcing is too much for the Milankovitch impacts to overcome. Equilibrium effects and climate sensitivity has nothing to do with it.

Again, you are denying the science on a false analysis.