Urban Methane Emissions Rise 10% Despite City Climate Pledges

TL;DR: Satellite monitoring reveals a 10% increase in urban methane emissions between 2020 and 2023, even as many cities promised reductions.

Cities account for roughly one‑tenth of the world’s methane output, a greenhouse gas that traps heat more efficiently than carbon dioxide but stays in the atmosphere for a shorter time. Cutting methane can therefore deliver rapid climate benefits.

A team led by Erica Whiting at the University of Michigan analyzed data from the Tropospheric Monitoring Instrument (TROPOMI), a satellite launched in 2017 that measures atmospheric gases globally. The researchers examined monthly methane concentrations over 92 cities from 2019 through 2023, covering both core urban areas and surrounding zones where landfills and wastewater plants sit.

The study found that after a modest dip in 2019‑2020, emissions rose by about 10% in the 51 C40 member cities—a coalition of 96‑country cities aiming to halve greenhouse gases by 2030—and by 12% in non‑C40 cities. The increase persisted despite formal pledges to cut methane by 34% within the same timeframe.

Rob Jackson, an Earth system scientist at Stanford University, noted that most regions show no sign of declining urban methane. He warned that the pandemic‑induced emission dip in early 2020 complicates interpretation, but the overall upward trend signals that cities are missing the Global Methane Pledge target of a 30% cut by 2030.

The rise may reflect growing urban populations, which expand the demand on waste‑management infrastructure and natural‑gas networks—key methane sources. Existing ground‑based inventories, limited to a few North American and European cities, have struggled to capture these dynamics, underscoring the value of satellite‑based monitoring.

For policymakers, the findings highlight a gap between ambition and measurable outcomes. Satellite data can now provide near‑real‑time feedback on the effectiveness of leak‑repair programs, composting initiatives, and landfill upgrades. As more cities adopt these tools, tracking progress will become more transparent.

What to watch next: Upcoming TROPOMI data releases and the 2025 city‑level methane reporting cycle will reveal whether new waste‑management projects and stricter gas‑infrastructure regulations can reverse the current upward trend.