Articles | Volume 25, issue 19
https://doi.org/10.5194/acp-25-12513-2025
https://doi.org/10.5194/acp-25-12513-2025
Research article
 | 
09 Oct 2025
Research article |  | 09 Oct 2025

Evaluating urban methane emissions and their attributes in a megacity, Osaka, Japan, via mobile and eddy covariance measurements

Masahito Ueyama, Taku Umezawa, Yukio Terao, Mark Lunt, and James Lawrence France

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Cited articles

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Short summary
Methane (CH4) emissions were measured in the megacity of Osaka, Japan, using mobile and eddy covariance methods. The CH4 emissions were much higher than those reported in local inventories, with natural gas contributing up to 74 % of the emissions. Several CH4 sources not accounted for in current inventories were identified. These results emphasize the need for more comprehensive emissions tracking in urban areas to enhance climate change mitigation efforts.
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