Coordination with mitigation uncertainty

To limit global warming to maximum 2◦C and ideally 1.5◦C, the Paris Agree- ment sets up a system of repeated ’pledge and review’ under which parties to the agreement are supposed to undertake progressively ambitious climate policies. ’Pledge’ involves that parties periodically submit Nationally Determined Contributions (NDCs), in which they outline the climate actions they plan to undertake. These contributions are subsequently subject to review. Our laboratory experiment is motivated by an observed large variance in the precision level of countries’ emissions reporting in the climate regime. The aim is to experimentally investigate the effects of transparent monitoring of compliance on countries’ ability to coordinate on avoiding a collective catastrophe such as climate change. To do this, we design a public goods game where groups of four contribute to a public good. If a certain threshold is not met subjects lose a portion of their endowment. We conduct a one shot game to investigate how uncertainty about the effectiveness of contribution affects coordination. We also examine this effect in a multi-period game, where subjects contribute over the course of five rounds. In addition, we implement a third treatment in the multi-period game to explore how uncertainty about subjects' contribution but not their effectiveness, affect coordination to reach the threshold.