Quantifying Fair Share Carbon Budgets

An obligation to quantify each country’s fair share of the remaining global carbon budget associated with limiting global heating to 1.5°C flows from the judgment in KlimaSeniorinnen. While there will naturally be debate about what represents a country’s fair share – the EU’s independent advisory body ESAB recently considered a range of fair share principles and concluded that the EU’s fair share has already been used up under many of these – the obligation to quantify fair share budgets should, in our view, be the subject of a reduced margin of appreciation consistent with KlimaSeniorinnen.