Global Critical
Zone Science
Chair
An interdisciplinary platform dedicated to understanding the Earth's critical zone and its role in environmental transitions.
Understanding the Critical Zone
The Global Critical Zone Science Chair at IAS–UM6P studies the Earth's "critical zone", the thin layer where rock, soil, water, air, and living organisms interact. This zone is key to understanding climate change, ecosystems, and resource sustainability.
Bringing together geoscientists, biologists, and environmental researchers, the Chair promotes interdisciplinary research on environmental processes and supports collaborations, conferences, and scientific training within IAS and the wider UM6P ecosystem.
Develops research on the functioning and evolution of the critical zone, exploring interactions between geological, biological, and atmospheric processes and their links to climate dynamics and water systems.
Through conferences, advanced schools, and scientific meetings, the Chair brings together international experts to foster interdisciplinary dialogue across IAS, UM6P research institutes, and global networks.
Positions IAS–UM6P as a hub for research on Earth systems and environmental change, integrating field research, modeling, and policy-relevant science to address climate change and land use challenges.
"The critical zone is where Earth's history is written, in the soil, in the rock, in the water. Understanding it is essential to navigating the environmental transitions of our time."
Formerly Aix-Marseille University
Daniel Nahon is an internationally recognized geochemist specializing in soils, laterites, and long-term Earth surface processes. Formerly Professor at Aix-Marseille University, his career has been dedicated to understanding the functioning of the Earth's critical zone and the complex interactions between geology, climate, and ecosystems.
His work forms the scientific foundation of the Chair, bringing decades of field-based expertise in tropical soils, mineral weathering, and environmental transitions to IAS UM6P's interdisciplinary research environment.
Research, Training & Conferences
In 2025, the Global Critical Zone Science Chair advanced its research agenda through international partnerships, scientific training programs, and collaborative workshops on soil systems, nutrient cycles, and environmental sustainability.
Engage with
Earth Science at IAS
Join the Chair's international network of critical zone researchers. Apply for a residency, propose a collaborative project, or participate in the Advanced School on Tropical Agriculture.