Methane remote sensing and emission quantification of offshore shallow water oil and gas platforms in the Gulf of Mexico

• Published in: Environmental Research Letters
• Main Authors: Alana K Ayasse, Andrew K Thorpe, Daniel H Cusworth, Eric A Kort, Alan Gorchov Negron, Joseph Heckler, Gregory Asner, Riley M Duren
• Format: Article
• Language: English
• Published: IOP Publishing 2022-01-01
• Subjects: methane; remote sensing; hyperspectral; imaging spectrometer; offshore oil and gas; methane plume mapping
• Online Access: https://doi.org/10.1088/1748-9326/ac8566

Offshore oil and natural gas platforms are responsible for about 30% of global oil and natural gas production. Despite the large share of global production there are few studies that have directly measured atmospheric methane emanating from these platforms. This study maps CH _4 emissions from shallow water offshore oil and gas platforms with an imaging spectrometer by employing a method to capture the sun glint reflection from the water directly surrounding the target areas. We show how remote sensing with imaging spectrometers and glint targeting can be used to efficiently observe offshore infrastructure, quantify methane emissions, and attribute those emissions to specific infrastructure types. In 2021, the Global Airborne Observatory platform, which is an aircraft equipped with a visible shortwave infrared imaging spectrometer, surveyed over 150 offshore platforms and surrounding infrastructure in US federal and state waters in the Gulf of Mexico representing ∼8% of active shallow water infrastructure there. We find that CH _4 emissions from the measured platforms exhibit highly skewed super emitter behavior. We find that these emissions mostly come from tanks and vent booms or stacks. We also find that the persistence and the loss rate from shallow water offshore infrastructure tends to be much higher than for typical onshore production.