More consistent assessment of uncertainties by the Intergovernmental Panel on Climate Change (IPCC)

Reports by the IPCC employ an evolving framework of calibrated language for assessing and communicating degrees of certainty in scientific findings. One challenge for this framework has been ambiguity in the relationship between multiple degree-of-certainty metrics. A new paper in the journal Climatic Change aims to better systematize the interrelation between the IPCC’s probability language and their confidence language, with benefits for consistency among findings and for usability in downstream modeling and decision analysis. [link to the article]

A broader philosophy of decision under severe uncertainty

All decision making involves figuring out what decision needs to be made, what your options are, and what information you need in order to evaluate those options. These activities are a part of what’s called the framing, or structuring, of decisions. A new paper in the journal Topoi argues that this aspect of decision making is even more important where uncertainty is severe, and that improving decision making and policy analysis under severe uncertainty requires better integration of knowledge about good framing practices and knowledge about other aspects of decision making, such as weighing the options. [link to the article]

Using experts’ judgements to inform adaptation planning for climate change

Cities and regions around the world are facing the impacts of climate change and planning for even greater impacts in the near future. These efforts to manage water supplies, respond to sea level rise, or protect infrastructure can be informed by regional climate change projections on decadal and multi-decadal timescales. While informative, these climate change projections are also highly uncertain, and national meteorological offices and other climate services providers are searching for the best approaches to quantifying and communicating this uncertainty.

The formal elicitation of experts’ judgements is a method of uncertainty quantification that has been used widely in other areas of application, but is so far under-utilised in climate change adaptation. Expert judgements are subjective, but they are also evidence-based, and eliciting these judgements in a careful, controlled, scientific manner is often the best—or even the only— way to integrate evidence from a variety of sources. Climate scientist Erica Thompson and philosophers Roman Frigg, and Casey Helgeson argue that structured expert elicitation should now be put to use for characterising uncertainties in regional climate change projections intended to inform adaptation decisions: Expert Judgment for Climate Change Adaptation, Philosophy of Science 83 (5):1110-1121 (2016). [link to journal article] [pdf from Philpapers archive]