Robustness over efficiency in climate coalitions: a bistable model and a map of architectures

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:Provides a novel theoretical framework for analyzing climate coalition stability, with testable implications for carbon pricing and border measures.

🏢実務担当者:Offers insights for corporate climate strategy regarding the likely durability of different international carbon pricing regimes.

🏛政策担当者:Highlights the importance of robustness in designing international climate agreements, suggesting that self-igniting architectures may be more sustainable.

Designs for international climate cooperation face a trade-off between allocative efficiency and robustness to the erosion of institutions by defection, renegotiation, and political turnover. We formalize this trade-off in a stylized coalition-formation game in which membership is driven by two market-based channels, a membership premium and an outsider drain, and is stabilized against a bounded set of institutional perturbations using the apparatus of robust control. The free-rider gap that each member faces is derived from economic primitives, the carbon price differential and the emission intensity of exports, and separated from the architecture-specific channels; the separation makes the model solvable and comparative. The model is bistable: a small remnant club and a near-universal coalition are separated by a critical mass. The established coalition withstands roughly twelve times the perturbation admissible at ignition, and the tipping survives heterogeneity up to a critical disorder of about seven times the membership premium. Two robustness coordinates, an ignition cost and a collapse threshold, place each entry architecture in a map with three regimes: self-igniting, founding-dependent, and permanent-support-dependent. The carbon currency, a newly proposed quantity-based system whose emission rights are reissued each period, extinguished upon use, and enforced at the border, is self-igniting; the border adjustment is founding-dependent; the export rebate is permanent-support-dependent. Architectures without an outsider drain, such as clean-up certificates and emissions-trading-system linking, form a separate class that improves efficiency within a coalition but cannot drive its formation. Robustness governs whether cooperation forms and endures; efficiency decides only how much an established coalition delivers.

• arXiv https://arxiv.org/abs/2608.12143first seen 2026-08-14 04:11:12