Lack of Consistency between Modeled and Observed Temperature Trends

Abstract

The US Climate Change Science Program [CCSP, 2006] reported, and Douglass et al. [2007] and NIPCC [2008] confirmed, a “potentially serious inconsistency” between modeled and observed trends in tropical surface and tropospheric temperatures. However, Santer et al. [2008: hereafter “Santer”], though sharing several co-authors with CCSP [2006], offered “new observational estimates of [tropical] surface and tropospheric temperature trends”, concluding that “there is no longer a serious discrepancy between modelled and observed trends.” Santer's key graph [shown here as Fig. 5] misleadingly suggests an overlap between observations and modeled trends. His “new observational estimates” conflict with satellite data. His modeled trends are an artifact, merely reflecting chaotic and structural model uncertainties that had been overlooked. Thus the conclusion of “consistency” is not supportable and accordingly does not validate model-derived projections of dangerous anthropogenic global warming (AGW).