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+--- Thread: Research Global urban methane emissions are growing more than estimated (/thread-20180.html)
Global urban methane emissions are growing more than estimated - C C - Apr 13, 2026
https://www.eurekalert.org/news-releases/1123927
KEY POINTS: Satellite measurements show that urban methane emissions around the globe have risen 6% since 2019, and emissions from C40 cities partaking in climate pledges are rising at a similar rate as non-participating cities. The observed growth in methane emissions is not captured by accounting-based emissions estimates, suggesting that some methane sources are missing or underestimated. C40 cities will have to account for nearly 2 additional teragrams of methane emissions—about 30% of their emissions reduction target.
INTRO: Urban emissions of methane—a potent greenhouse gas—are rising faster than "bottom-up" accounting estimates anticipated, according to a study led by University of Michigan Engineering and funded by NASA and the National Institute of Standards and Technology.
The discrepancy was found with satellite measurements of methane over 92 major cities around the world. For 72 of the cities, there were sufficient data to track changes in methane emissions between 2019 and 2023. Overall, global urban methane emissions in 2023 were 6% higher than 2019 levels and 10% higher than 2020 levels, although they tended to decrease in European cities.
In contrast, accounting methods—which tally emission estimates of individual methane sources—suggest that urban methane emissions have only risen between 1.7% and 3.7% since 2020.
The study included over half of the C40 network, a group of 97 cities around the world aiming to reach net-zero emissions by 2050. Total methane emissions across all the studied C40 cities in 2023 were also 10% higher than 2020 levels, and the cities will have to contend with an extra 2 teragrams of methane emissions per year, which is about 30% of their emission reduction targets. The gap between official estimates and satellite measurements warn that city policies designed with accounting estimates may not reduce methane emissions as desired.
"In order to reduce greenhouse gas emissions and set good emissions policy, cities need to know how much they are emitting and what those sources are. But there is quite a bit of uncertainty with that for methane," said Eric Kort, corresponding author of the study published in Proceedings of the National Academy of Sciences. He advised the study's lead author as a U-M professor of climate and space sciences and engineering, and is now director of the Atmospheric Chemistry Department at the Max Planck Institute for Chemistry... (MORE - details, no ads)
RE: Global urban methane emissions are growing more than estimated - Syne - Apr 14, 2026
Urban methane emissions primarily originate from anthropogenic activities, with key sources including landfills, aging natural gas distribution systems, wastewater treatment plants, and residential combustion. These sources often lead to city-scale emissions being underestimated, as they represent a major, often concentrated, share of total human-caused emissions.
- Google AI