As the impact of humans on the biosphere and geosphere intensifies, it is becoming critical to better understand the drivers of diversity, change, and stability within and between these spheres. Ambitious cross-disciplinary projects, such as Germany’s new TERRA initiative, are therefore needed. The backbone of this project is the hypothesis that diversity in the geosphere stabilizes the biosphere, and that vice versa biodiversity is key to stabilizing the geosphere. TERRA combines field, experimental, and modelling approaches to interrogate feedbacks between diversity and stability during the past and present to evaluate the effectiveness of future mitigation strategies. In the spirit of TERRA we invite submissions across spatial and temporal scales that link the geo- and biosphere. We are particularly interested in studies that cross traditional disciplinary boundaries and that address the potential of geodiversity and biodiversity as stabilizing factors in the Earth system.