états-unis, climatoscepticisme, conquête de l’ouest, frederick turner, frontier, homestead act, dust bowl, john steinbeck, les raisins de la colère, dorothea lange, gaz de schiste, fracture hydraulique, yellowstone, yosemite, théodore roosevelt, franklin delano roosevelt, civilian conservation corps, national park service, rachel carson, printemps silencieux, clean air act, clean power plan, agence américaine de l’environnement, we are still in, donald trump, jerry brown, michael bloomberg, giec, al gore, protocole de Kyoto, greenwashing, john kerry