Epistemic Uncertainties in Climate Predictions: A Challenge for Practical Decision Making

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Rafaela Hillerbrand


Most scientists agree that, at least for the time being, unquantified uncertainties are inevitably connected to predictions of climate models. Uncertainties, however, do not justify political inaction. This paper addresses the question of how epistemic uncertainties are of relevance for practical decision making. It is shown how common decision approaches based on the precautionary principle fail to adequately deal with uncertainties as they arise in climate modeling. I argue that with regards to climate change, unquantified uncertainties can neither be ignored in decision making nor be reduced to quantified ones by assigning subjective probabilities. This distinguishes the ethical problems associated with climate change from other problems regarding energy supply and demand like, for example, those associated with nuclear power.

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Author Biography

Rafaela Hillerbrand, RWTH Aachen

Rafaela Hillerbrand studied physics and philosophy in Erlangen, Münster, Liverpool and Nice and holds a doctorate in both fields. Her research interests lie in the area of philosophy of science and philosophy of technology. Before she took up her current position as head of the research program ‘Ethics for Energy Technology’ at the Human & Technology Center, RWTH Aachen University, she worked as a research fellow at the University of Oxford.


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