The Global Stocktake
How the Paris Agreement's built-in review mechanism works, what the first Global Stocktake revealed, and why it matters for ratcheting up climate ambition.
The Ratchet Mechanism
The Paris Agreement was designed with a fundamental insight: the initial commitments countries made in 2015 were insufficient to limit warming to 1.5 or even 2 degrees. The architecture relies on a 'ratchet mechanism' where countries submit increasingly ambitious climate pledges (Nationally Determined Contributions, or NDCs) every five years. The Global Stocktake is the engine of this ratchet: a comprehensive assessment of collective progress toward the Paris goals, conducted every five years to inform the next round of NDCs.
The first Global Stocktake concluded at COP28 in December 2023. The technical assessment, prepared over the preceding two years, was blunt: the world is not on track. Current policies would lead to roughly 2.5-2.9 degrees of warming by 2100, far above the Paris targets. Emissions need to fall 43 percent by 2030 relative to 2019 levels to stay on a 1.5-degree path, but current pledges fall far short of this trajectory.
