Implications of various effort-sharing approaches for national carbon budgets and emission pathways

Implications of various effort-sharing approaches for national carbon budgets and emission pathways

van den Berg, N.J. (Universiteit Utrecht; PBL Netherlands Environmental Assessment Agency)
van Soest, Heleen L. (Universiteit Utrecht; PBL Netherlands Environmental Assessment Agency)
Hof, Andries F. (Universiteit Utrecht; PBL Netherlands Environmental Assessment Agency)
den Elzen, Michel G.J. (PBL Netherlands Environmental Assessment Agency)
van Vuuren, Detlef P. (Universiteit Utrecht; PBL Netherlands Environmental Assessment Agency)
Chen, Wenying (Tsinghua University)
Drouet, Laurent (Fondazione Centro Euro-Mediterraneo sui Cambiamenti Climatici)
Fujimori, Shinichiro (Kyoto University; National Institute for Environmental Studies of Japan)
Blok, K. (TU Delft Energie and Industrie; TU Delft TU Delft Services)

TU Delft Services

2019

The bottom-up approach of the Nationally Determined Contributions (NDCs) in the Paris Agreement has led countries to self-determine their greenhouse gas (GHG) emission reduction targets. The planned ‘ratcheting-up’ process, which aims to ensure that the NDCs comply with the overall goal of limiting global average temperature increase to well below 2 °C or even 1.5 °C, will most likely include some evaluation of ‘fairness’ of these reduction targets. In the literature, fairness has been discussed around equity principles, for which many different effort-sharing approaches have been proposed. In this research, we analysed how country-level emission targets and carbon budgets can be derived based on such criteria. We apply novel methods directly based on the global carbon budget, and, for comparison, more commonly used methods using GHG mitigation pathways. For both, we studied the following approaches: equal cumulative per capita emissions, contraction and convergence, grandfathering, greenhouse development rights and ability to pay. As the results critically depend on parameter settings, we used the wide authorship from a range of countries included in this paper to determine default settings and sensitivity analyses. Results show that effort-sharing approaches that (i) calculate required reduction targets in carbon budgets (relative to baseline budgets) and/or (ii) take into account historical emissions when determining carbon budgets can lead to (large) negative remaining carbon budgets for developed countries. This is the case for the equal cumulative per capita approach and especially the greenhouse development rights approach. Furthermore, for developed countries, all effort-sharing approaches except grandfathering lead to more stringent budgets than cost-optimal budgets, indicating that cost-optimal approaches do not lead to outcomes that can be regarded as fair according to most effort-sharing approaches.

http://resolver.tudelft.nl/uuid:37f86dc1-865e-4e68-befd-9d1c5c7bce48

https://doi.org/10.1007/s10584-019-02368-y

0165-0009

Climatic Change: an interdisciplinary, international journal devoted to the description, causes and implications of climatic change, 162 (4), 1805-1822

Institutional Repository

journal article

© 2019 N.J. van den Berg, Heleen L. van Soest, Andries F. Hof, Michel G.J. den Elzen, Detlef P. van Vuuren, Wenying Chen, Laurent Drouet, Shinichiro Fujimori, K. Blok, More Authors