The analysis at Reference 1 presents a method and equation that accurately calculates average global temperatures since 1895 without considering any influence from change to the level of carbon dioxide or any other greenhouse gas in the atmosphere.
The coefficient of determination, R2, (R2 is discussed in Ref 2) for that calculation is 0.8686 which means that the equation explains 86.86% of the measured average global temperature (agt) anomalies. This is better than has been achieved by any Global Climate Model. The agt anomaly identified in Ref 1 as a prediction is more correctly called a calculation up to the present and a projection (for the condition of no sunspots) thereafter.
The Ref 2 paper includes a determination of the possible influence that added atmospheric CO2 might have on average global temperature. It is a refinement of the previous work which was presented in Ref 1. The Ref 2 work showed that, although assuming no effect of added atmospheric CO2 produced an excellent correlation with measured agt, when a significant contribution from added atmospheric CO2 is included an excellent correlation is also produced, in fact, a tiny bit better.
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