Georgia Athletic Association Distinguished Professor of Atmospheric Sciences and Geography, University of Georgia

Shepherd is a leading international expert in weather and climate and the Georgia Athletic Association Distinguished Professor of Atmospheric Sciences and Geography at the University of Georgia. He is the host of The Weather Channel’s award-winning Sunday talk show and podcast Weather Geeks, and a contributor to Forbes Magazine. Shepherd is a former NASA scientist and winner of numerous awards, including the prestigious AMS Helmut Landsberg Award for pioneering significant work in urban climate. Shepherd is frequently sought as an expert on weather, climate, and remote sensing—he routinely appears on leading broadcast programs around the world. Follow him on Twitter and visit his website.

Hear more about equitable climate action in Unit 1, which covers 50 years of stunning change—from food demand, water, population, ocean health, and beyond.

Professor and Canada Research Chair in Global Environmental Change and Food Security, University of British Columbia

Ramankutty, a professor and research chair at the University of British Columbia, leads a program that explores how humans use and modify the Earth’s land surface for agriculture—and how that implicates our global environment. Using research observations and numerical ecosystem models, he aims to find solutions to the problem of feeding humanity with minimal global environmental footprint. Ramankutty—a Leopold Leadership Fellow—contributed to the Millennium Ecosystem Assessment report and to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, and currently serves as Associate Editor of Environmental Research Letters. Follow Ramankutty on Twitter and visit his website.

Hear more about the sources of greenhouse gas emissions in Unit 2, which covers three need-to-know principles of equitable climate solutions.

Angel investor, clean energy advocate, award-winning author

Naam is a pioneering thought leader focused on climate and energy, speaking frequently on the inevitability and increasing price advantage of clean energy. He serves as advisor and investor to clean energy, mobility, and climate-related startups around the world. Born in Cairo, Egypt before moving to the U.S. at age three, Naam began his career at Microsoft before moving on to work on clean energy and climate change. Naam has written five books, including the nonfiction bestseller The Infinite Resource: The Power of Ideas on a Finite Planet. Follow him on Twitter and visit his website.

Hear more about fascinating energy solutions in Unit 5, which outlines clear paths to safe, equitable, and comprehensive climate action. 

Director of the Institute on the Environment, University of Minnesota

Hellmann is the director of the University of Minnesota’s Institute on the Environment and the Ecolab Chair in Environmental Leadership, where she works to build a future where people and planet prosper together. Her research focuses on global change ecology, climate adaptation, and the reduction of greenhouse gas emissions. Widely published and a skilled communicator, Hellmann is a scientific pioneer routinely called upon by leading international media outlets to provide expert input on global change. In addition to several prestigious fellowship positions, she received the Climate Adaptation Leadership Award of the US Association of Fish and Wildlife Agencies. Follow Hellmann on Twitter, visit her website, and read her blog Director’s Almanac.

Hear more about ecosystem impacts in Unit 4, which digs into carbon sinks—and ways to keep them strong—around the world.