The Ambition Trap: Why Overpromising on Climate Action Could Undermine Progress

Under cross-pressure to pledge deep emissions cuts and deliver concrete climate policy actions, how should policymakers navigate the tension between ambition and compliance prospects? Although highly ambitious climate pledges are needed to achieve the Paris Agreement’s long-term targets, overly ambitious pledging can engender non-compliance in the longer term. Devoid of compliance enforcement, the Paris Agreement risks an ‘ambition trap’, whereby policymakers are tempted to pledge ever-more ambitious targets without devising sufficiently strong policy instruments to ensure their implementation. This article argues that the difficulties of implementing overly ambitious pledges threaten the credibility of international climate cooperation. We report two main empirical findings. First, we demonstrate the existence of a trade-off between ambition and compliance prospects in the Nationally Determined Contributions: the most ambitious pledges have substantially lower chance of being achieved. Second, based on a conjoint experiment in five major democracies, we show that the public is far more concerned about implementation likelihood than target stringency. Our findings jointly suggest that policymakers seeking to safeguard the credibility of the Paris Agreement should prioritize urgent implementation of climate policies rather than pledging ever-more ambitious climate targets.