Dataset Information

Strong methane point sources contribute a disproportionate fraction of total emissions across multiple basins in the United States.

ABSTRACT: Understanding, prioritizing, and mitigating methane (CH₄) emissions requires quantifying CH₄ budgets from facility scales to regional scales with the ability to differentiate between source sectors. We deployed a tiered observing system for multiple basins in the United States (San Joaquin Valley, Uinta, Denver-Julesburg, Permian, Marcellus). We quantify strong point source emissions (>10 kg CH₄ h^-1) using airborne imaging spectrometers, attribute them to sectors, and assess their intermittency with multiple revisits. We compare these point source emissions to total basin CH₄ fluxes derived from inversion of Sentinel-5p satellite CH₄ observations. Across basins, point sources make up on average 40% of the regional flux. We sampled some basins several times across multiple months and years and find a distinct bimodal structure to emission timescales: the total point source budget is split nearly in half by short-lasting and long-lasting emission events. With the increasing airborne and satellite observing capabilities planned for the near future, tiered observing systems will more fully quantify and attribute CH₄ emissions from facility to regional scales, which is needed to effectively and efficiently reduce methane emissions.

SUBMITTER: Cusworth DH

PROVIDER: S-EPMC9499563 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Strong methane point sources contribute a disproportionate fraction of total emissions across multiple basins in the United States.

Cusworth Daniel H DH Thorpe Andrew K AK Ayasse Alana K AK Stepp David D Heckler Joseph J Asner Gregory P GP Miller Charles E CE Yadav Vineet V Chapman John W JW Eastwood Michael L ML Green Robert O RO Hmiel Benjamin B Lyon David R DR Duren Riley M RM

Proceedings of the National Academy of Sciences of the United States of America 20220913 38

Understanding, prioritizing, and mitigating methane (CH4) emissions requires quantifying CH4 budgets from facility scales to regional scales with the ability to differentiate between source sectors. We deployed a tiered observing system for multiple basins in the United States (San Joaquin Valley, Uinta, Denver-Julesburg, Permian, Marcellus). We quantify strong point source emissions (>10 kg CH4 h-1) using airborne imaging spectrometers, attribute them ...[more]

PMID: 36099297

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Dataset Information

Strong methane point sources contribute a disproportionate fraction of total emissions across multiple basins in the United States.

Publications

Strong methane point sources contribute a disproportionate fraction of total emissions across multiple basins in the United States.

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