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Judith Curry: Stalking The Uncertainty Monster

Judith Curry, Climate Etc.

Its time to check in with the Climate Uncertainty Monster.



The occasion for this post is an invitation to present a keynote talk at the 2nd International Workshop on Econometric Applications in Climatology.  The Workshop website is [here.]

To those of you that are new to Climate Etc., the concept of the ‘climate uncertainty monster’ seeded my inaugural posts at Climate Etc. in 2010 (Tag Uncertainty for entire series, see especially the earlier posts).

New presentation

My new ppt presentation can be downloaded here [uncertainty].  Check out the presentation; lots of good monster cartoons. Below is the text of my prepared remarks (I rambled on at the end including some material from my recenttestimony that isn’t included in these remarks):

I’ve long been concerned about how the IPCC treats uncertainty, and in 2003 I started gathering my thoughts on this. A seminal event in my thinking on this subject occurred in 2010, when I attended the Royal Society Meeting on Scientific Uncertainty.

Let me start by describing the uncertainty monster, in context of the debate on climate change.  The “monster” is a metaphor used in analysis of the response of the scientific community to uncertainties at the climate science-policy interface. Confusion and ambiguity is associated with:

  • * knowledge versus ignorance
  • * objectivity versus subjectivity
  • * facts versus values
  • * prediction versus speculation
  • * science versus policy

The climate uncertainty monster has its roots in philosophy and sociology.  Monster theory regards monsters as symbolic expressions of cultural unease that pervade a society and shape its collective behavior.  Dutch philosopher Martijntje Smits articulated the monster as co-existence of public fascination and discomfort with newer technologies.  Dutch social scientists Jeroen van der Sluijs articulated the ‘uncertainty monster’ as related to ways in which the scientific community responds to the monstrous uncertainties associated with environmental problems.

By way of introduction to this topic, I’m going to go through some uncertainty monster coping strategies, that are in evidence at the interface between climate science and policy.

Uncertainty monster hiding or the “never admit error” strategy can be motivated by a political agenda or because of fear that uncertain science will be judged as poor science by the outside world.  Apart from the ethical issues of monster hiding, the monster may be too big to hide and uncertainty hiding enrages the monster.

Ignoring the monster is typified by this statement from President Obama’s web page:  Call out the Climate Deniers – 97% of scientists agree.  A dubious paper that found a 97% consensus on fairly trivial aspects of climate change is then morphed into 97% of scientists agree that human-caused climate change is dangerous.

Monster simplifiers attempt to transform the monster by subjectively quantifying and simplifying the assessment of uncertainty. Monster simplification is formalized in the IPCC  by guidelines for characterizing uncertainty in a consensus approach consisting of expert judgment in the context of a subjective Bayesian analysis.

The uncertainty monster exorcist focuses on reducing the uncertainty through advocating for more research. In the 1990’s, a growing sense of the infeasibility of reducing uncertainties in global climate modeling emerged in response to the continued emergence of unforeseen complexities and sources of uncertainties.  For each head climate science chops off the uncertainty monster, several new monster heads tend to pop up.

The first type of uncertainty monster detective is the scientist who challenges existing theses and works to extend knowledge frontiers.  A second type is the watchdog auditor, whose main concern is accountability, quality control and transparency of the science. A third type distorts and magnifies uncertainties as an excuse for inaction for financial or ideological reasons.

Monster assimilation is about learning to live with the monster and giving uncertainty an explicit place in the contemplation and management of environmental risks.  Assessment and communication of uncertainty and ignorance, along with extended peer communities, are essential in monster assimilation. The challenge to monster assimilation is the ever-changing nature of the monster and the birth of new monsters.

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. The IPCC uses a common vocabulary to express quantitative levels of confidence based on the amount of evidence (number of sources of information) and the degree of agreement (consensus) among experts.   Because of the difficulties of objective uncertainty assessments, the IPCC relies primarily on expert judgment in the context of a subjective Bayesian analysis.  A quantitative likelihood scale represents ‘a probabilistic assessment of some well-defined outcome having occurred or occurring in the future.’

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