Methane Emissions from Offshore Oil and Gas Platforms in the Gulf of Mexico
Open Access
- 9 March 2020
- journal article
- research article
- Published by American Chemical Society (ACS) in Environmental Science & Technology
- Vol. 54 (6), 3530-3538
- https://doi.org/10.1021/acs.est.9b07148
Abstract
Shipboard measurements of offshore oil and gas facilities were conducted in the Gulf of Mexico in February 2018. Species measured at 1 s include methane, ethane, carbon-13 (13C) and deuterium (D) isotopes of methane, and several combustion tracers. Significant variability in the emission composition is observed between individual sites, with typical ethane/methane ratios around 5.3% and 13C and D methane isotopic compositions around −40 and −240‰, respectively. Offshore plumes were spatially narrower than expectations of the plume width based on terrestrial atmospheric stability classes; a modified Gaussian dispersion methodology using empirically measured horizontal plume widths was used to estimate the emission rates. A total of 103 sites were studied, including shallow and deepwater offshore platforms and drillships. Methane emission rates range from 0 to 190 kg/h with 95% confidence limits estimated at a factor of 10. The observed distribution is skewed with the top two emitters accounting for 20% of the total methane emissions of all sampled sites. Despite the greater throughput of the deepwater facilities, they had moderate emission rates compared to shallow-water sites. Analysis of background ethane enhancements also suggests a source region in shallow waters. A complete 1 s measurement database is published for use in future studies of offshore dispersion.Keywords
Funding Information
- Climate and Clean Air Coalition
This publication has 29 references indexed in Scilit:
- Methane fluxes to the atmosphere from deepwater hydrocarbon seeps in the northern Gulf of MexicoPublished by American Geophysical Union (AGU) ,2012
- Composition and fate of gas and oil released to the water column during the Deepwater Horizon oil spillProceedings of the National Academy of Sciences of the United States of America, 2011
- Atmospheric emissions from the Deepwater Horizon spill constrain air-water partitioning, hydrocarbon fate, and leak rateGeophysical Research Letters, 2011
- Methane flux to the atmosphere from the Deepwater Horizon oil disasterGeophysical Research Letters, 2011
- Tracking Hydrocarbon Plume Transport and Biodegradation at Deepwater HorizonScience, 2010
- Methane in the Baltic and North Seas and a reassessment of the marine emissions of methaneGlobal Biogeochemical Cycles, 1994
- Fugitive Hydrocarbon Emissions from Pacific Offshore Oil Platforms: Models, Emission Factors, and Platform EmissionsAir & Waste, 1993
- Development and Evaluation of the Offshore and Coastal Dispersion ModelJournal of the Air Pollution Control Association, 1985
- The concentration and isotopic abundances of carbon dioxide in rural and marine airGeochimica et Cosmochimica Acta, 1961
- The concentration and isotopic abundances of atmospheric carbon dioxide in rural areasGeochimica et Cosmochimica Acta, 1958