Climate change and other anthropogenic impacts are exposing ecosystems to more frequent and intense extreme events, raising an urgent need for understanding how ecological systems respond to extremes. However, many ecological concepts and theories were developed to describe systems near equilibrium, within some historical range(s) of variability. Whether these concepts and theories can be extrapolated to ecosystems during extreme events, such as novel disturbances, nutrient pulses, or climatic extremes is unclear. Modern means of observation and experimentation are expanding our ability to document how systems have responded to recent and historic environmental extreme events. New statistical methods for analyzing extreme events are emerging, as are new process-based models of ecological systems during extreme events. The time is ripe to gain deeper insight—and greater predictive power—by connecting the conceptual and theoretical perspectives to real-world observations.

Speakers in this session will describe how their focal system responded to extreme events, then discuss whether observed responses are consistent with previous conceptual and mechanistic understanding of the system. Several speakers will discuss research that takes a modeling approach, testing whether modeled systems show qualitative change under extreme conditions.

As a group, we will ask: Were responses to extreme events surprising because they exceeded past magnitudes of ecological change, or because systems were unexpectedly resistant or resilient? When ecological responses to extremes bend or break our conceptual/theoretical framework, how do we modify our theoretical models? And, where are the gaps in our mechanistic understanding of ecological response to extreme events?