Fairness- and cost-effectiveness-based approaches to effort-sharing under the Paris agreement

The current nationally determined contributions of the Parties to the Paris Agree-ment are far from being sufficient to achieve the long-term goal to limit global warming. Therefore, the question of how to distribute the global mitigation burden among the Parties in a fair and cost-effective way remains topical. In this paper, approaches based on different fairness criteria and the criterion of cost-effective-ness are applied to a global emission budget compatible with the Paris targets and evaluated for the globally largest emitters including the EU as well as Ger-many. The results show that domestic mitigation efforts need to be increased in the majority of those countries even more than for the below-2êC limit of the Can-cun Agreements. Moreover, even if the cost-effective level is assumed to be reached, there remains a strong need for support by the historical large emitters to others from a fairness perspective.