Speaker: Prof. Judith A. Curry (Georgia Institute of Technology)
Abstract: How to understand and reason about uncertainty in climate science is a topic that is receiving increasing attention in both the scientific and philosophical literature. This paper provides a perspective on exploring ways to understand, assess and reason about uncertainty in climate science, including application to the Intergovernmental Panel on Climate Change (IPCC) assessment reports. Uncertainty associated with climate science and the science-policy interface presents unique challenges owing to complexity of the climate system itself, the potential for adverse socioeconomic impacts of climate change, and politicization of proposed policies to reduce societal vulnerability to climate change. The challenges to handling uncertainty at the science-policy interface are framed using the 'monster' metaphor, whereby attempts to tame the monster are described. Uncertainty of climate models is interpreted in the context of model inadequacy, uncertainty in model parameter values, and initial condition uncertainty. The challenges of building confidence in climate models are described. The treatment of uncertainty in the IPCC assessment reports is examined, including the IPCC 4th Assessment Report conclusion regarding the attribution of climate change in the latter half of the 20th century. Ideas for monster taming strategies are discussed for institutions, individual scientists, and communities.