Prof. Joeri Rogelj, Director of Research at the Grantham Institute and Professor of Climate Science and Policy at the Centre for Environmental Policy at Imperial College London, a Senior Research Scholar at the International Institute for Applied Systems Analysis (IIASA), conducts world-leading research connecting climate and earth system science with policy and societal change. One Earth recently spoke with him about the impacts of temperature overshoot and the research needed to address the unknowns of going beyond the historic “safe operating space” of human civilization—and the process of returning.