To forecast the effects of more frequent extreme climatic events on population dynamics we first need to be able to answer the question of attribution. Attribution requires detecting that extremes have a biological impact, which is challenging due to the intrinsic rarity of extreme events. Furthermore, attribution requires that this impact cannot be credited to other factors, which is challenging in observational studies because many other aspects of the environment are changing concurrently. Attribution of extreme climatic events is particularly challenging because changes in climatic extremes are typically correlated with changes in other aspects of climate (mean and variability), which are also important for population dynamics. I will review studies that have distinguished the effects of changes in extremes from changes in mean and variability on population dynamics.
Results/Conclusions
Interestingly, the results of these few attribution studies tentatively suggest that the impacts of extremes are less important than changes in means and variability, which sharply contrasts many studies that suggest catastrophic impacts of climate extremes (but have not performed formal attribution). I will offer possible explanations why this contrast may exist. Furthermore, I will discuss the usefulness of attribution, and when it may or not make sense to focus on climatic extremes.