Gidon Eshel, Ph.D. is a Professor of Environmental Physics at Bard College in New York, and runs the website environmentalCalculations.com. Professor Eshel specializes in oceanography, climatology, and geophysics. He is the author of Spatiotemporal Data Analysis (Princeton University Press, 2011) and the forthcoming Planetary Eating (MIT Press 2024 or 2025). Recent publications include an article on sustainable beef production for Nature Ecology & Evolution and an analysis on the climate impact of intensive vs. pastoral beef that was highlighted in Nature’s Research Highlights. His work has also appeared in Climatic Change, Environmental Research Letters, Environmental Science & Technology, Proceedings of the National Academy of Sciences, Earth Interactions, and American Journal of Clinical Nutrition, among other publications. He is best known for his work quantifying the geophysical consequences of agriculture and diet. Most recently, he has compared various livestock in terms of land and water use, fertilizer-based water pollution, and greenhouse gas emissions per unit product and compared the global-warming consequences of different beef-production strategies (including grass-versus trough-fed beef). His widely varied scientific interests also include the development of algebraic tools for simultaneous optimization of health and environmental outcomes through dietary choices, climate physics, and measures of time scale–specific ecosystem stability.