John E. Tilton

饰：Himself, research professor, Colorado School of Mines

Amy Coen

饰：Herself, CEO Population Action International

Anu Ramaswami

饰：Herself, Urban Sustainable Infrastructure Engineering Project

J. Carl Ganter

饰：Himself, director, Circle of Blue

Kathleen A. Miller

饰：Herself, National Center for Atmospheric Research

Shemin Ge

饰：Herself, Department of Geological Sciences, University of Colora

Alan Mazzotti

饰：Himself, family farm owner

Josette Shiner

饰：Herself, executive director, World Food Program

Joseph Kikabi

饰：Himself

爱德华·威尔逊

Edward O. Wilson

饰：Himself, professor and curator of entomology

Richard Heinberg

Richard Heinberg

饰：Himself, author of `Peak Everything`

Randy Udall

Randy Udall

饰：Himself, co-founder ASPO-USA

James Howard Kunstler

James Howard Kunstler

饰：Himself, author of `The Long Emergency`

Alexandra Cousteau

饰：Self - Founder of Blue Legacy

Ted Nordhaus

饰：Self - Co-Author of 'Break Through: From the Death of Environmentalism to the Politics of Possibility'

Stephen Lekson

饰：Self - Curator of Anthropology, University of Colorado,(as Steve Lekson)

Michael Shellenberger

Michael Shellenberger

饰：Self - Co-Author of 'Break Through: From the Death of Environmentalism to the Politics of Possibility'