A consequential framework to quantify the climate impacts of passenger travel

Transportation analyses rely almost exclusively on attributional carbon accounting methods, which can distort the ‘carbon footprint’ of passenger travel and estimated effects of mitigation strategies. This commentary aims to facilitate a transition to consequential carbon accounting in transportation, a sector that contributes a large and growing share of global greenhouse gas emissions. A conceptual framework for consequential accounting of the climate impacts from passenger travel is proposed, which requires characterization of a counterfactual. An analytical framework is then developed to apply the consequential framework. Finally, research directions are described to advance consequential carbon accounting methods in transportation analysis.