Every IPCC report first passes through a vetting process where every country in the world as well as every corporate stakeholder must agree with the report's conclusions. The Scientific American article makes a valid complaint that the IPCC process is too conservative saying that, "When there is conflicting evidence of something, the IPCC has tended to say nothing in an effort not to upset anybody." And there's a wide range of anybodies not to upset.
As Sarah van Gelder says in a recent Guardian article, "There's controversy among environmentalists regarding 'whether to downplay the dangers' of global warming for fear of frightening people or being accused of being 'alarmist' by opponents." IMO most folks, when hearing that scientists are spinning their results, will instinctively distrust them, or anyone else, for using a strategy to slant information one way or another.
The article titled 'Climate Scientists Erring on the Side of Least Drama' at Skeptical Science explains why so many climate scientists are biased toward overly cautious estimates, erring on the side of less rather than more alarming predictions, which they call "erring on the side of least drama" (ESLD). It has many cool and easy to understand graphs and graphics along with a very readable text that refers often to a paper recently published in Global Environmental Change titled 'Why Climate Scientists Have Consistently UNDERestimated Key Global Warming Impacts'. In this paper the authors, Brysse et al., examined research evaluating past climate projections, and considered the pressures which might cause climate scientists to ESLD.
As Martin Luther King once said, "It's always the right time to do the right thing". Sounds like good advice for climate science and those producing the upcoming IPCC 5th Assessment. Tomorrow's Mud Report will outline some of the scientific reasons why noted environmentalists like Dr. James Hansen have concluded that, in the long term, climate is twice as sensitive in the real world as it is in the models used by the IPCC.
