http://www.skepticalscience.com/climate ... -esld.html"Erring on the Side of Least Drama" (ESLD) to Avoid Alarmism
The IPCC and climate scientists are often accused of "alarmism", but clearly Brysse et al. demonstrates that these accusations are wholly unfounded and misplaced.
"Our analysis of the available studies suggests that if a bias is operative in the work of climate scientists, it is in the direction of under-predicting, rather than over-predicting, the rate and extent of anthropogenic climate change."
In fact, Brysse et al. suggest that these frequent accusations of "alarmism" and other climate contrarian attacks on climate scientists may be one reason why climate scientists have under-predicted climate change, or erred on the side of least drama.
"The frequent attacks on Stephen Schneider—as well as attacks on other climate scientists such as Benjamin Santer and Michael Mann—suggests that one possible reason why scientists may have underestimated the threat of anthropogenic warming is the fear that if they don’t, they will be accused by contrarians (as was Schneider) of being alarmist fear-mongers. That is to say, pressure from skeptics and contrarians and the risk of being accused of alarmism may have caused scientists to understate their results."
However, Brysse et al. note that from a scientific and statistical standpoint, under-predicting an effect by 10% is no less wrong than over-predicting an effect by 10%. Therefore, ESLD can introduce a systematic bias that leads to a reduction in the accuracy of climate projections.
http://www.sciencedirect.com/science/ar ... 8012001215Abstract
Over the past two decades, skeptics of the reality and significance of anthropogenic climate change have frequently accused climate scientists of “alarmism”: of over-interpreting or overreacting to evidence of human impacts on the climate system. However, the available evidence suggests that scientists have in fact been conservative in their projections of the impacts of climate change. In particular, we discuss recent studies showing that at least some of the key attributes of global warming from increased atmospheric greenhouse gases have been under-predicted, particularly in IPCC assessments of the physical science, by Working Group I. We also note the less frequent manifestation of over-prediction of key characteristics of climate in such assessments. We suggest, therefore, that scientists are biased not toward alarmism but rather the reverse: toward cautious estimates, where we define caution as erring on the side of less rather than more alarming predictions. We call this tendency “erring on the side of least drama (ESLD).” We explore some cases of ESLD at work, including predictions of Arctic ozone depletion and the possible disintegration of the West Antarctic ice sheet, and suggest some possible causes of this directional bias, including adherence to the scientific norms of restraint, objectivity, skepticism, rationality, dispassion, and moderation. We conclude with suggestions for further work to identify and explore ESLD.
