Using large-scale climate indices in climate change ecology studies

Recently, climate change research in ecology has embraced the use of large-scale climate indices in long-term, retrospective studies. In most instances, these indices are related to large-scale teleconnection and atmospheric patterns of which over a dozen have been identified. Although most of these relate to different geographical areas, many are related and interact. Consequently, even the simple task of selecting one to use in ecological research has become complicated, despite our ability to disentangle the results from analyses involving large-scale climate indices. Leaning upon recent reviews of the definition and functioning of large-scale climate indices, as well as reviews on the relationship between these and concomitant changes in ecological variables, we focus here on the usefulness of large-scale climate indices in different aspects of climate change ecology. By providing a general framework for using climate indices, we illustrate the potential advantages of their utility by integrating three case histories focusing on two groups of evolutionarily distinct organisms: birds and mammals.