Accidentally edited ZM's post instead of quoting. Sorry.
ZM's post along my replies is below.
Typhoon wrote:Nonc Hilaire wrote:MS0qLhqaZDM
For those interested in the devil in the details
Climate Etc. - Ross McKitrick | Are Climate Models Overstating Warming?
One should keep in mind that the major part of these climate model simulations are not from first principles: fluid mechanics, thermodynamics, etc., as the computing power to do so does not yet exist. Rather they consist mostly of fitting thousands of parameters to empirical - observational data.
Somewhat useful for studying climate, but with no predictive ability.
This is false. Even GCMs are based on fluid and thermodynamic models.
Current models, due to existing computing limitations, are not even close to the spatial-temporal resolution required to be full first principles fluid + thermodynamic models. If this was the case, then the models would all converge to close agreement.
Instead, massive approximations are made using hundreds of empirical parameters a.k.a. guesstimates.
With four parameters I can fit an elephant, and with five I can make him wiggle his trunk.
~ John von Neumann
Resulting in a dog's breakfast of predictions all of which predict a larger rise in the global temperature anomaly than has been observed.
That the entire climate cannot be simulated from first principles does not invalidate modeling as the best possible investigative approach upon which to base policy decisions.
The current models are toy models, useful for study climate, but with no predictive skill and utility.
Typhoon wrote:The fundamental science behind CO2-driven warming is very well understood.
Yes. Direct CO2 infrared absorption leads to a logarithmic saturating increase in warming.
MODTRAN
This fundamental physics does not give the temperature rise range predicted by the models.
To generate more CO2 driven warming, the models assume additional, empirically unobserved, effects such as CO2 - water vapour positive feedback.
Yet global humidity has not risen.
Along with assumptions about clouds, i.e., the role of the dominant greenhouse gas - water vapour.
It is also well understood that there is no alternative hypothesis that explains both the rising atmospheric carbon concentration and warming trend. Interestingly, Judith Curry (your lone credible source as of late) would strongly disagree with your view on climatology. This article does not support your views. A "systemic error" does not imply the models are useless.
Quite.
Systemic errors, i.e., intrinsic incorrect biases, indicate that the models are wrong and thus less than useless for prediction and policy.
The alternative hypothesis is obvious. Natural climate variation given that climate is a driven dynamic process far from thermodynamics equilibrium.
Or in layman's terms, the climate has been constantly changing since the earth first had a climate.
It is notable that that the time series of purported global anomaly temperature rise since ~1890 cannot cannot be distinguished from a random time series.
Unlike climate change hysterics, the activist MSM, and yourself, the APS [American Physical Society] knows who are the experts in the field.
APS Climate Change Statement Workshop
Invited Experts:
Dr. John Christy
Dr. William Collins
Dr. Judith Christy
Dr. Isaac Held
Dr. Richard Lindzen
Dr. Benjamin Santer
Given what is both known and -- crucially -- unknown about climate processes, you cannot make a rational argument that carbon emissions should continue unabated. They must be slashed, even if that means a temporary decline in "standard of living."
Speculative extrapolation, promoting a ruinous policy, unsupported by evidence.
May the gods preserve and defend me from self-righteous altruists; I can defend myself from my enemies and my friends.