Storylines of climate variability for hydrological impact studies

Physical climate storylines (physically-based unfoldings of past climate or weather events, or of plausible future events or pathways) are increasingly being used to represent the epistemic uncertainty in the forced response to climate change. But storylines can also be used to systematically explore the uncertainty space of climate variability, e.g. to construct plausible worst-case events. Their use in this latter context is perhaps less obvious since variability is generally considered to be an aleatoric rather than an epistemic uncertainty. However, for impact studies, variability is often hugely undersampled, which is a serious problem that storylines can help address. In this talk I will review the rationale behind the use of storylines, discuss some of the concerns and questions about storylines that continue to arise, and provide some examples of their use in this particular context and of how storyline and probabilistic representations of uncertainty can be usefully combined.