Raymond T. Pierrehumbert is Halley Professor of Physics at the University of Oxford. He was a lead author on the IPCC Third Assessment Report, and co-author on several National Research Council reports concerning climate change. He was awarded a John Simon Guggenheim Fellowship in 1996, which was used to launch collaborative work on the climate of Early Mars with collaborators in Paris. He is a Fellow of the American Geophysical Union, and of the American Academy of Arts and Sciences, and has been named Chevalier de l’Ordre des Palmes Académiques by the Republic of France. Pierrehumbert’s central research interests concern the physics of Earth’s climate over time, as well as the climates of planets in our solar system and the exoplanets beyond.