Ruth DeFries is the Denning University Professor of Sustainable Development and co-founding Dean of the Climate School at Columbia University.

Dr. DeFries examines human transformation of the landscape and its consequences for climate, biogeochemical cycling, biodiversity, and other ecosystem services that make our planet habitable. The work is based on the premise that land-use change involves tradeoffs between human necessities such as food and unintended environmental consequences such as greenhouse gas emissions and habitat loss. A particular focus is evidence-based strategies to balance development and conservation goals in dry tropical forested regions of India. Dr. DeFries examines land-use changes over broad scales through the lens of satellite observations.

Previously, Dr. DeFries was a professor in the Geography Department at the University of Maryland, staff at the National Research Council with the Committee on Global Change and taught at the Indian Institute of Technology in Bombay. She was elected to the U.S. National Academy of Sciences in 2006 and the American Association for the Advancement of Science in 2008, is a fellow of the Aldo Leopold Leadership Program, and received a MacArthur Foundation “genius” award in 2007.