Carbon is forever: A climate change experiment on cooperation

Greenhouse gases generate impacts that can last longer than human civilization itself. Such persistence may affect the behavioral ability to cooperate. In a laboratory experiment, we study mitigation efforts with dynamic externalities in a framework that reflects key features of climate change. In treatments with persistence, pollution cumulates and generates damages over time, while in another treatment it has only immediate effects and then disappears. We show that with pollution persistence, cooperation is initially high but then systematically deteriorates with high stocks of pollution.