Climate Sensitivity and the Responsiveness of Temperature to Atmospheric CO2

Abstract

Detrended correlation analysis of global mean temperature observations and model projections are compared in a test for the theory that surface temperature is responsive to atmospheric CO2 concentration in terms of GHG forcing of surface temperature implied by the Climate Sensitivity parameter ECS. The test shows strong evidence of GHG forcing of warming in the theoretical RCP8.5 temperature projections made with CMIP5 forcings. However, no evidence of GHG forcing by CO2 is found in observational temperatures from four sources including two from satellite measurements. The test period is set to 1979-2018 so that satellite data can be included on a comparable basis. No empirical evidence is found in these data for a climate sensitivity parameter that determines surface temperature according to atmospheric CO2 concentration or for the proposition that reductions in fossil fuel emissions will moderate the rate of warming.