Widespread misestimates of greenhouse gas emissions suggest low carbon competence

As concern with climate change increases, people seek to behave and consume sustainably. This requires understanding which behaviours, firms and industries have the greatest impact on emissions. Here we ask if people are knowledgeable enough to make choices that align with growing sustainability intentions. Across five studies, we (1) demonstrate that accuracy of individuals’ emissions-related estimates is limited, (2) provide evidence that this misestimation is consistent with a cognitive process of attribute substitution and (3) identify conditions that do (and do not) moderate estimation accuracy. Our findings suggest that individuals’ efficacy as consumers, investors and citizens is currently hampered by their misjudgements of carbon impact. We advocate accessible and easily understandable information that highlights the causal impact of consumption decisions to facilitate climate action. Individual actions are important to reduce emissions, yet consumers’ carbon incompetence may lead to ineffective efforts. This study demonstrates the consistent inaccuracy in assessing emissions of behaviours, firms and industries, which may be driven by lack of information or expertise.