Standing there, the reality of the situation weighed extra heavy: methane accounts for roughly 30% of current global warming and is 84 times more potent than CO₂ over a 20-year period. Emissions are still rising. And we have less than four years until 2030, by which point we need to cut global anthropogenic methane emissions by at least 30% from 2020 levels.
This means we must now shift from the decade of debate to the decade of delivery.
The Global Methane Pledge now comprises almost 160 countries committed to a 30% reduction by 2030. That political signal matters. But pledges made at the national level often need to be delivered locally. Methane reduction is a climate emergency brake, and the Global Methane Pledge will not be achieved without subnational governments.
States, provinces, cities, and regions control waste systems, shape agricultural practices, and regulate local infrastructure. They’re closest to the emissions sources and closest to the communities bearing the consequences. Yet they are consistently underserved: data exists but isn't always actionable at the local level; finance is not reaching subnational actors; and the partnerships needed to scale action remain fragmented.
The missing links are not ambition or and technology; they’re finance and implementation.
The good news is - and there is genuine good news - we’re already seeing what works. Subnational governments are making headway, tackling the three biggest sources of methane emissions: agriculture (~40%), fossil fuels (~30%), and waste (~20%).
On agriculture, Minas Gerais in Brazil offers one of the most compelling examples of what smart intervention looks like. Through its Genetic Quality Improvement Program for the Cattle Herd, the state has reduced its herd by 2 million animals while simultaneously increasing milk production from 7.3 billion to 9.4 billion litres. Fewer animals, greater output, lower emissions. In Cross River State, Nigeria, climate-smart rice farming is cutting methane from paddies while sustaining food yields by utilising subsurface irrigation and laser land levelling.
On fossil fuels, British Columbia has delivered a 51% reduction in methane emissions from oil and gas through targeted regulation and enforcement – not only hitting its target but beating it ahead of schedule. That kind of progress, achieved through policy alone, demonstrates what’s possible when subnational governments are given the mandate and the tools to act. Underpinning action like this is better data: California's $100 million satellite methane detection programme (CalSMP) is enabling real-time identification of emission plumes, shortening the time between detection and mitigation from months to days.
And on waste, the Sudokwon landfill in South Korea has become a global benchmark: capturing landfill methane and converting it into energy for hundreds of thousands of homes, turning a liability into a local energy asset. In Goiás, Brazil, the Zero Dumpsites Programme is tackling the problem upstream by diverting organic waste before it ever reaches landfill and eliminating one of the most avoidable sources of methane in the process.
Despite all this progress, current emission trajectories still point upward. That’s because the barriers are systemic. Too many subnational governments lack bankable project pipelines. Too few have direct access to climate finance. And alignment between national targets and local delivery remains weak.
This is precisely why the Subnational Methane Action Coalition (SMAC) exists; to support governments with data, technical assistance, peer learning, and access to finance. The challenge is how to scale it fast enough.
Methane action must be embedded into long-term climate strategies, integrated into national NDCs, and woven into subnational planning for air quality and public health. The systems we build – or fail to build – over the next years will determine whether 2030 is the turning point we need it to be.
The Angera Declaration, a 10-point action plan backed by 250 scientists, represents a science-grounded roadmap for what must happen next on methane. This is not a call for new commitments. It’s a call to act on what we already know.
The declaration represents the will of positive changemakers like the European Commission, Spark Climate Solutions, the Climate & Clean Air Coalition, the Environmental Defense Fund, Global Carbon Project, UN Environment Programme, and the Institute for Governance & Sustainable Development.
I was pleased to sign this declaration in person at the conference and would encourage subnational governments and colleagues working in the space to read, sign, share, and act on these recommendations.
Two hundred and fifty years of science brought us here. How we mobilise funding and drive project implementation can change what comes next. Subnational governments are not supporting actors in this story - they are central to its outcome.
The science is clear. The solutions, often at low cost, are available. The question is whether we can deliver at speed, and at scale.
You can learn more about the work of the Subnational Methane Action Coalition.