Closing the fossil carbon cycle: the Geological Net Zero Pact (FR : Boucler le cycle du carbone fossile : le pacte de Neutralité Géologique en Carbone)
Description
Closing the fossil carbon cycle: the Geological Net Zero Pact. Working version 0.9
Climate disruption results first of all from the transfer of carbon accumulated over millions of years in geological reservoirs into the atmosphere, the ocean and the biosphere, at a pace that natural cycles cannot offset. The Geological Net Zero (GNZ) principle was proposed for COP26 in 2021 and has since been consolidated in the scientific literature. It draws an accounting rule from this: any extraction of fossil carbon must be balanced by a permanent and verified return of carbon to the geosphere.
Between COP26 and COP31, the carbon budget compatible with 1.5 °C shrank from 420 to 170 billion tonnes of CO₂. This document reviews that period and explains why a pact between carbon actors is preferable to a resolution imposed from above. It then presents the GNZ Pact:
- implementation by segments of supply chains, spreading until a critical threshold is reached;
- its parties and its five commitments;
- its accounting and the economic model it induces;
- how it fits with atmospheric CO₂ removal and with fossil fuel transition roadmaps.
It ends with a flexible action plan based on demonstrators and verifiable commitments.
Contents of this record
- Founding article, French and English versions
- Perspective, condensed version for journal submission, French and English versions
Status. Working version 0.9, released on the occasion of COP31 (Antalya, 9–20 November 2026) and subject to revision; version 1.0 is expected in December 2026. This is a scientific and public-policy proposal open for discussion. It does not refer to an adopted treaty or an existing certification scheme, and it does not reflect the position of any organisation or person cited.
Website: geologicalnetzero.org
Abstract (French)
Boucler le cycle du carbone fossile : le pacte de Neutralité Géologique en Carbone. Version de travail 0.9
Le dérèglement climatique résulte d’abord du transfert du carbone accumulé pendant des millions d’années dans les réservoirs géologiques vers l’atmosphère, l’océan et la biosphère, à un rythme que les cycles naturels ne peuvent compenser. Le principe de neutralité géologique en carbone (Geological Net Zero, GNZ) a été proposé pour la COP26 en 2021 et consolidé depuis dans la littérature scientifique. Il en tire une règle comptable : toute extraction de carbone fossile doit être équilibrée par une restitution permanente et vérifiée de carbone à la géosphère.
Entre la COP26 et la COP31, le budget carbone compatible avec 1,5 °C est passé de 420 à 170 milliards de tonnes de CO₂. Ce document fait le point sur cette période et explique pourquoi un pacte entre les acteurs du carbone est préférable à une résolution imposée d’en haut. Il présente ensuite le pacte GNZ :
- une mise en œuvre par segments de chaînes d’approvisionnement, qui se propage jusqu’à un seuil critique ;
- ses parties et ses cinq engagements ;
- sa comptabilité et le modèle économique qu’il induit ;
- son articulation avec les retraits de CO₂ atmosphérique et avec les feuilles de route de sortie des fossiles.
Il se termine par un plan d’action souple, fondé sur des démonstrateurs et des engagements vérifiables.
Contenu de la fiche
- Article fondateur, versions française et anglaise
- Perspective, version condensée pour soumission à une revue, versions française et anglaise
Statut. Version de travail 0.9, diffusée à l’occasion de la COP31 (Antalya, 9-20 novembre 2026) et soumise à révision ; version 1.0 prévue en décembre 2026. Il s’agit d’une proposition scientifique et de politique publique, soumise à discussion. Elle ne désigne ni un traité adopté ni un dispositif de certification existant, et n’engage aucune des organisations ou personnes citées.
Site : geologicalnetzero.org
Files
GNZ_Pact_founding_article_v0.9_2026-11-06_EN.pdf
Additional details
References
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