The problem with existing climate models:
Even those who aver that man’s activity affects climate on a global scale rather than just locally or regionally appear to accept that the existing climate models are incomplete. It is a given that the existing models do not fully incorporate data or mechanisms involving cloudiness or global albedo (reflectivity) variations or variations in the speed of the hydrological cycle and that the variability in the temperatures of the ocean surfaces and the overall ocean energy content are barely understood and wholly inadequately quantified in the infant attempts at coupled ocean/atmosphere models. Furthermore the effect of variability in solar activity on climate is barely understood and similarly unquantified.
As they stand at present the models assume a generally static global energy budget with relatively little internal system variability so that measurable changes in the various input and output components can only occur from external forcing agents such as changes in the CO2 content of the air caused by human emissions or perhaps temporary after effects from volcanic eruptions, meteorite strikes or significant changes in solar power output.
If such simple models are to have any practical utility it is necessary to demonstrate that some predictive skill is a demonstrable outcome of the models. Unfortunately it is apparent that there is no predictive skill whatever despite huge advances in processing power and the application of millions or even billions of man hours from reputable and experienced scientists over many decades.
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