Interesting link from Sam (at Elizaphanian) by Judith Curry “Climate Change – no consensus on consensus“.
The issue is to escape the denial, and simply recognize the big science decisions – to agree or criticize with “findings” are not scientific, they are political, tactical, strategic, etc … value-based.
The key IPCC consensus finding from its latest assessment report is this statement:
“Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.”
The IPCC consensus findings on attribution have been echoed in position statements made by many scientific organizations. The IPCC consensus is portrayed as nearly total among scientists with expertise and prominence in the field of climate science. The idea of a scientific consensus surrounding climate change attribution has been questioned by a number of people, including scientists and politicians. Much effort has been undertaken by those that support the IPCC consensus to discredit skeptical voices, essentially dismissing them as cranks or at best rebels, or even politically motivated ‘deniers’.
That is, both sides need to recognize that they are politically motivated. It discredits science when scientists claim to be being scientific when they are clearly (and quite rightly) not.
How to reason about uncertainties in the complex climate system and its computer simulations is neither simple nor obvious. Scientific debates involve controversies over the value and importance of particular classes of evidence as well as disagreement about the appropriate logical framework for linking and assessing the evidence. The IPCC faces a daunting challenge with regards to characterizing and reasoning about uncertainty, assessing the quality of evidence, linking the evidence into arguments, identifying areas of ignorance and assessing confidence levels. An overarching concern is how the issue of climate change is framed scientifically and how judgements about confidence in complex scientific arguments are made in view of the cascade of uncertainties.
Given the complexity of the climate problem, ‘expert judgements’ about uncertainty and confidence levels are made by the IPCC on issues that are dominated by unquantifiable uncertainties. It is difficult to avoid concluding that the IPCC consensus is manufactured and that the existence of this consensus does not lend intellectual substance to their conclusions.
No, but it’s practically useful trust and authority they are meant to create, not “intellectual substance”.
So, ultimately, I don’t actually agree with the conclusions of the paper, that somehow because the IPCC consensus on climate change was “manufactured” and had unintended “denial” consequences, the consensus creation was therefore wrong. No, what is wrong is the expectation that consensus (on “wicked” as opposed to “linear” or “tame” questions) is anything other than manufactured. It is always about establishing some political authority on practical decision-making. Only the weak-minded confuse that with imposing “dogma” on science. The science goes on.
As with any politics its about trusting those you entrust with authority and the checks and balances your system has. There is no “solid evidence” to back judgements, however much the scientistic fundamentalists demand evidence-based policy.