CIRCE studies the importance of complexity for how ecosystems function and respond to environmental change, focusing on three major complexity factors: species interactions, dispersal, and environmental variability. While clearly affecting ecosystems, their general importance, how they interact, and the mechanisms involved are disputed. Also contentious is how to predict their effects under climate change. CIRCE addresses this by developing analytical frameworks for describing complexity, analyzing how complexity and system characteristics co-vary in space and time, and developing predictive models that integrate complexity.

CIRCE employs an informatics approach, analyzing large ecological data sets using advanced statistical and mechanistic modeling.