PhD – Charlotte Demonsant – Climate action and fairness

International climate negotiations, the « yellow vests » crisis after the carbon tax increase, the difficulties of voluntary agreements: climate mitigation seems caught in a dilemma between effectiveness and fairness. The thesis traces its origin to the theoretical frameworks underlying mitigation instruments. Drawing on IPCC Working Group III reports (1990–2023), it shows how mitigation has been framed as a « collective action problem » over a common resource.

It then draws on the general average rule from maritime law, under which sacrifices made to save a venture from a common peril are shared by all, in proportion to the value saved. Its modelling shows that « common rescue » creates a decisive interdependence: one party’s effort saves the others. Framing climate change as a common peril thus opens a way to reconcile fairness and effectiveness, which the thesis illustrates with air quality and Low Emission Zones.