Could Doubling CO2 Increase Earth’s Temperature by 9 Degrees C?

by Emil Morhardt

That is the assertion of a paper in Nature by Carolyn W. Snyder (Snyder, 2016) based on an analysis of the correlation between atmospheric CO2 concentrations and changes in the global average surface temperature (GAST) over the past 800,000 years. Actually the assertion is that the 95% “credible interval” is 7 to 13 degrees Celsius (12.6 to 23 degrees Fahrenheit) Yikes! Even the current scientific consensus value of something on the order of 3 C (5.4 F) (Collins et al., 2013) is frightening when you consider that the difference in the GAST between the last glacial maximum about 20,000 years ago and at present wasn’t much different than that. Continue reading