evidence: The results: 10 of the model projections closely matched observations. Moreover, after accounting for differences between modeled and actual changes in atmospheric carbon dioxide and other factors that drive climate, the number increased to 14. The authors found no evidence that the climate models evaluated either systematically overestimated or underestimated warming over the period of their projections. "The results of this study of past climate models bolster scientists’ confidence that both they as well as today’s more advanced climate models are skillfully projecting global warming," said study co-author Gavin Schmidt, director of NASA’s Goddard Institute of Space Studies in New York. "This research could help resolve public confusion around the performance of past climate modeling efforts." [...] Schmidt says climate models have come a long way from the simple energy balance and general circulation models of the 1960s and early ‘70s to today’s increasingly high-resolution and comprehensive general circulation models. "The fact that many of the older climate models we reviewed accurately projected subsequent global temperatures is particularly impressive given the limited observational evidence of warming that scientists had in the 1970s, when Earth had been cooling for a few decades," he said.