Democratic Underground - Here's Hansen's graph that Crichton lies about

"Next, and slightly more troubling, we have some rather misleading and selective recollection regarding Jim Hansen’s testimony to congress in 1988. “Dr. Hansen overestimated by 300 percent” (p247). Hansen’s testimony did indeed lead to a big increase in awareness of global warming as a issue, but not because he exaggerated the problem by 300%. In a paper published soon after that testimony, Hansen et al, 1988 presented three model simulations for different scenarios for the growth in trace gases and other forcings (see figure). Scenario A had exponentially increasing CO2, Scenario B had a more modest Business-as-usual assumption, and Scenario C had no further increases in CO2 after the year 2000. Both scenarios B and C assumed a large volcanic eruption in 1995. Rightly, the authors did not assume that they knew what path the carbon dioxide emissions would take, and so presented a spectrum of results. The scenario that ended up being closest to the real path of forcings growth was scenario B, with the difference that Mt. Pinatubo erupted in 1991, not 1995. The temperature change for the decade under this scenario was very close to the actual 0.11 C/decade observed (as can be seen in the figure). So given a good estimate of the forcings, the model did a reasonable job. In fact in his testimony, Hansen ONLY showed results from scenario B, and stated clearly that it was the most probable scenario. The ‘300 percent’ error claim comes from noted climate skeptic Patrick Michaels who in testimony in congress in 1998 deleted the bottom two curves in order to give the impression that the models were unreliable."

http://www.realclimate.org/index.php?p=74#more-74

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