Dag O. Hessen
Dag Olav Hessen is a Norwegian biologist and Professor at the University of Oslo. He is widely recognized for his research on aquatic systems, ecology, and evolution, as well as for his influential public communication on biology, environmental issues, and nature conservation.
He earned his cand.real. degree in zoology in 1982, completed intermediate studies in public law in 1984, and received his dr.philos. in biology in 1988. He was appointed Professor of Biology at the University of Oslo in 1993. Hessen has been a member of the Norwegian Academy of Science and Letters since 1998, and from 2025 also a member of the Norwegian Academy of Technological Sciences.
Since 2018, he has led the interdisciplinary Centre of Biogeochemistry in the Anthropocene (CBA) at the University of Oslo, a research hub focused on climate systems, feedback mechanisms, and the global carbon cycle.