Article 6 of the Paris Agreement: A Comprehensive Review of Mechanisms, Progress, and Persistent Challenges

Phalguni Deswal

Managing Editor, Drug and Device World, Kurukshetra, India.

Abstract

The Paris Agreement represents a transformative shift in global climate governance to limit temperature rise and climate change by introducing Article 6 as a cornerstone for international cooperative action. The paper provides a comprehensive review and critical analysis of Article 6, with a dedicated focus on its three core operational pathways: Article 6.2 [decentralised cooperative approaches], Article 6.4 [centralised UN-supervised crediting mechanism – Paris Agreement Crediting Mechanism (PCMS)], and Article 6.8 [non-market approaches]. The paper examines the foundational principles underpinning Article 6, including internationally transferred mitigation outcomes (ITMOs), mitigation contribution units (MCUs), Article 6.6 emission reductions (A6.4ERs), corresponding adjustments (CAs) to prevent double counting, the Share of Proceeds (SOP) to the Adaptation Fund (AF), and the requirement for overall mitigation in global emissions (OMGE). The paper assesses early implementation efforts, such as bilateral agreements under Article 6.2 and the operationalisation of the Article 6.4 mechanism, while highlighting persistent challenges, including methodological rigour, compatibility, additionality, and the integration of nature-based solutions. Drawing on insights from recent Conference of the Parties (COP) meetings and key stakeholder perspectives, the analysis identifies critical gaps in governance, transparency, and environmental integrity. The paper also addresses significant criticisms, such as the risk of nature-based emission reductions, REDD+ activities, greenwashing, the oversupply of low-quality credits, and the complex interplay between compliance and voluntary carbon markets. Ultimately, this study underscores the potential of Article 6 to lower mitigation costs, channel finance to developing countries, and raise global ambition, while cautioning that its success hinges on robust implementation, unwavering environmental integrity, and the resolution of outstanding technical and political hurdles.

Keywords: Climate change; Paris Agreement; Article 6.2; Article 6.4; Conference of the Parties (COP); Nationally Determined Contributions (NDCs); Internationally transferred mitigation outcomes (ITMOs); Mitigation contribution units (MCUs); Corresponding adjustments (CAs); Double counting; Share of Proceeds (SOP); Adaptation fund (AF); Overall mitigation in global emissions (OMGE); REDD+

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