Emissions Measurements are Not Drag and Drop: Reconciling Short-term Emissions Measurements with Annual Inventory Averages

Emissions inventories of atmospheric pollutants such as greenhouse gases (GHGs) are used to identify emissions reduction targets, inform regulatory and policy action, and as inputs to broader chemistry and climate models. Methane is a potent but relatively short-lived GHG with an atmospheric lifetime of ~12 years, making it an attractive target for immediate emission reductions for climate action. Methane emissions from oil and gas (O&G) operations contribute to approximately 1/3 of global methane emissions. Since methane emissions from O&G are due to a combination of intentional engineering designs and unintentional engineering failures, reducing O&G methane emissions is the lowest hanging fruit for methane emissions reductions.

Emissions inventories of methane from O&G operations underpin regulatory and business decisions made around which engineering designs and failures to target for emissions reductions but measurement campaigns over the last decade indicate that methane emissions inventories do not match emissions realities. Most often, studies find that emissions inventories likely underpredict total methane emissions. The CSU Methane Emissions Technology Evaluation Center (METEC) group is involved in areas of improving methane emissions inventories and measurements. I will highlight a few key projects and tools from METEC, with an emphasis on how we can combine “next-generation” measurements with “old-school” statistical modeling to improve emissions inventories.