Beyond the Snapshot: A decade of net zero commitments

"Climate change is a movie, not a picture." 

This observation was first made by former UN Climate Change High-Level Champion Gonzalo Muñoz at COP26 in Glasgow in 2021, encouraging those disappointed by the negotiations to conceive of climate progress not as a single moment, but as part of a much broader story. The remark captures the challenge at the heart of climate governance, offering vital clues for activists, researchers and policymakers alike.

At the Net Zero Tracker, progress is often assessed through snapshots: how many countries have set net zero targets, how many companies have committed to decarbonisation, and how many cities have adopted climate goals. Our flagship Net Zero Stocktake report has long tracked such coverage, whilst distinguishing between coverage and robustness, and how these two so often diverge.  

The recently launched, long-awaited Historical Time Series dataset, the product of years of work, aims to begin to fill the longitudinal research gap. It is the first publicly available record of how net zero commitments have evolved across more than 4,000 governments and companies since the adoption of the Paris Agreement in 2015. The initial release focuses on net zero target data, with further robustness and integrity indicators to follow.

We hope that this dataset reveals a new lens through which to view, and analyse the transition. For academics, it creates new analytical possibilities, from tracking robustness over time to asking whether, for example, offset commitments have become more transparent. For policymakers, the data can reveal which interventions accelerated adoption and which didn’t. For activists, it provides a sharper basis for holding companies and governments to account against their own record, and for those creating net zero strategies sectorally, it makes it possible to weigh a company's trajectory against the pace and credibility of its peers.

The net zero wave

Looking across a decade of data, the history of net zero has been characterised as a story with distinct chapters, a series of shifts Professor Thomas Hale has described as the transformation of net zero as a relatively obscure concept, to a demand made by activists, to a mainstream organising policymaking principle, and finally into a more complex, messier phase of implementation. The particular transition of net zero as a scientific concept to guidance principle in governance , is what became known as the ‘net zero wave’. This mirrors the finding of academics Thomas Hale, Jessica Green and Aldrick Arceo, whose research found that net zero pledges grew far faster than their robustness, interim targets became more common over time, while transparent use of offsets lagged behind. The Historical Time Series builds on this foundation of work, tracing this drift continuously across the decade since Paris. 

Early exploration of the dataset suggests that apparent cases of corporate backtracking are often more complex than they first appear, sometimes reflecting revised target definitions or corrected records rather than a genuine loss of ambition, a distinction only longitudinal data can identify. As project Lead John Lang noted at the dataset's launch, understanding how policy, markets, technology and public support interact to create the reinforcing ‘ambition loops’ needed to accelerate decarbonisation is only possible if we can see the dynamics of how change develops over time.

Methodology: A citizen science programme 

Such a significant gap in the data required a huge amount of effort, skill and coordination to try and fill. Built using a transparent coding methodology based on publicly available primary sources, the dataset draws on years of work by more than 700 trained volunteers from 92 countries, who undergo training and peer review, with every data point checked and reconciled before publication. In an era of rapid expansion of generative AI models, this human effort and expertise remains crucial in distinguishing meaningful change from mere platitudes. Interpreting the nuance of policy documents and corporate disclosures still relies on careful human judgement rather than automation.

The Dataset

The dataset is structured as a monthly panel covering the period from 2015 to today, tracking how key characteristics of net zero commitments, target years, interim targets, emissions coverage, reporting mechanisms have evolved across more than 4,000 governments and companies. The Net Zero Tracker team is looking forward to seeing where researchers, policymakers and practitioners take this data next, and what it reveals about the direction of climate ambition over the coming years.

Frances Green, Programme Manager, Net Zero Tracker