Outsourcing decarbonization? How trade shaped France’s carbon footprint (2000–14)[Externalisation de la décarbonisation ? Comment le commerce a façonné l'empreinte carbone de la France (2000-2014)]

This study investigates the evolution of France's carbon footprint from 2000 to 2014, with a particular focus on the role of international trade. During this period, France's territorial emissions decreased by 18%, yet its consumption-based footprint declined by only 5%. This divergence reflects an increase in emissions embedded in imports, which grew from 45% to 54% of the total. To analyze these dynamics, we develop a novel structural decomposition framework that disentangles the contributions of scale, composition, and technique effects from a consumption perspective. Our approach extends existing methods by explicitly distinguishing between domestic and foreign influences, and by separately analyzing trade openness and the geographic reallocation of imports. The results highlight the dominance of the technique effect in reducing emissions (-28%), driven primarily by efficiency improvements abroad rather than domestic progress. By contrast, the geographic composition effect substantially increased emissions (+18%), particularly before 2008, when France's import sourcing shifted toward more carbon-intensive trading partners such as China. France's situation is emblematic of economies that have already achieved relatively low domestic emissions—through nuclear energy and de-industrialization—and have thus become increasingly dependent on foreign improvements for further reductions. This reliance raises concerns about the externalization of mitigation outcomes and underscores the limits of climate strategies focused solely on territorial emissions. Our findings call for stronger coordination between trade and climate policies to ensure that future decarbonization pathways remain consistent with global mitigation objectives.