Scientists used satellite data over 92 major cities. For 72 cities there was enough data to compare 2019 to 2023. Overall, global urban methane emissions in 2023 were 6% higher than in 2019 and 10% higher than in 2020.
By contrast, bottom-up accounting that adds up local sources showed only a small rise since 2020. This gap means policies based on those counts may not cut methane as expected.
The study looked at many C40 cities that aim for net-zero by 2050. In those cities methane in 2023 was 10% higher than in 2020, adding about 2 teragrams per year and affecting their reduction goals.
Difficult words
- satellite — object in space that sends data
- compare — look at two things for differences
- emission — gas released into the air by activitiesemissions
- accounting — method of adding up numbers or sources
- gap — difference or space between two values
- policy — plan or rule made by a governmentpolicies
- net-zero — equal amount of emissions and removals overall
- teragram — unit of mass equal to one trillion gramsteragrams
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Why might policies based on local counts fail to cut methane?
- What could city leaders do if methane is higher than their reduction goals?
- Do you know any local rules about air pollution? Give one example.
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