evidence: "Enormously complex:" specifically, "a few scientists can be found who privately suggest that because of complex feedback phenomena the net effect of increased CO2 might be global cooling," Abelson (1977). BACK 52a. Gates (1979). BACK 53. "Our confidence in our conclusion... is based on the fact that the results of the radiative-convective and heat-balance model studies can be understood in purely physical terms and are verified by the more complex GCM's. The last... agree reasonably well with the simpler models..." National Academy of Sciences (1979), p. 12. For the Panel’s workings see Bell (2021), p. 284. BACK 54. National Academy of Sciences (1979), pp. 2, 3; see Stevens (1999), pp. 148-49. for Manabe’s account see also Stokstad (2004). Hansen's model was not published until 1983. Already in 1977 W.W. Kellogg, reporting to the WMO, had arrived at the same 3°C "with an uncertainty of roughly a factor of two,"Kellogg (1977), p. vii. Confidence: Bony et al. (2011); on this period in general see Heymann (2013). BACK 55. Hansen et al. (1981); for details of the model, see Hansen et al. (1983). I heard "march with both feet in the air" from physicist Jim Faller, my thesis adviser. BACK 56.