Jessica A. Rowland , Emily Nicholson, Jose-Rafael Ferrer-Paris, David Keith, Nicholas Murray, Chloe Sato, Aniko Toth, Arn Tolsma, Susanna E. Venn, Marianne Asmüssen, Patricio Pliscoff, Carlos Zambrana-Torrelio, Rebecca Lester, Tracey Regan

Climate change has pervasive impacts on Earth’s ecosystems, but the diversity and complexity of ecosystems makes estimating the severity of impacts and the resulting risk of collapse difficult. In this perspective, we conceptualise the challenge of understanding how climate change alters ecosystems, and how to reliably measure those changes in ecosystem risk assessments, focussing on the IUCN Red List of Ecosystems. We propose solutions to resolve these challenges – using diverse teams, conceptual models, diverse using data sources including projections, learning from analogous ecosystems, and evaluating uncertainties – and we identify research gaps to bridge these challenges. Together, these solutions will improve our capacity to produce reliable assessments of collapse risk under climate change to inform timely and effective ecosystem conservation.