To further explore the effect of climate and decision factors, the project polled
14 experts for responses to some 30 prescribed scenarios of climate change,
coverage of impacts sectors, and decision choices (such as discount rate). The
experts included well-known advocates for a high SCC as well as for low SCC
values. Each expert was asked to rate their confidence in each response. The
responses were not benchmarked in any way—the interviewer did not prompt
the respondent to anchor the range or the mid-point. The experts received the
results with an opportunity to comment on the conclusions—but this was not an
iterative exercise nor was it designed to achieve a consensus among the experts.
Of the nearly 450 scenario-responses, fully 70% had a confidence rating of very
low or low. None of the scenarios were judged a confidence of very high and
only 3% had a high confidence.