Geographic distribution of industry-reported venting volumes of methane in Alberta in 2016. Selected measurement regions are indicated with black squares. Graphic: Johnson, et al., 2017 / Environmental Science & Technology

By Ashifa Kassam
17 October 2017
TORONTO (The Guardian) – Alberta’s oil and gas industry – Canada’s largest producer of fossil fuel resources – could be emitting 25 to 50% more methane than previously believed, new research has suggested.The pioneering peer reviewed study, published in Environmental Science & Technology on Tuesday, used airplane surveys to measure methane emissions from oil and gas infrastructure in two regions in Alberta. The results were then compared with industry-reported emissions and estimates of unreported sources of the powerful greenhouse gas, which warm the planet more than 20 times as much as similar volumes of carbon dioxide.“Our first reaction was ‘Oh my goodness, this is a really big deal,” said Matthew Johnson, a professor at Carleton University in Ottawa and one of the study’s authors. “If we thought it was bad, it’s worse.”Carried out last autumn, the survey measured the airborne emissions of thousands of oil and gas wells in the regions. Researchers also tracked the amount of ethane to ensure that methane emissions from cattle would not end up in their results.In one region dominated by heavy oil wells, researchers found that the type of heavy oil recovery used released 3.6 times more methane than previously believed. The technique is used in several other sites across the province, suggesting emissions from these areas are also underestimated.In the second region, home to a mix of gas and light oil wells, researchers found results that were roughly equal to those reported by industry and unreported sources. However, they found that only 6% of methane emissions in this region were from industry-reported sources, with the remaining emissions, known as fugitive emissions, from unreported sources such as unintentional equipment leaks.The finding could have major implications as Alberta and Ottawa strive to reduce methane emissions by 45% from 2012 levels by 2025, said Johnson. “It shows how much isn’t captured in current reporting requirements, and therein is a challenge and an opportunity all wrapped in one.” [more]

‘This is a really big deal’: Canada natural gas emissions far worse than fearedMethane measurement regions of interest near the cities of Lloydminster and Red Deer in Alberta. The background contour grid shows the local magnitudes of reported venting using the same color scale as Figure 2. Gray dots added in (a) and (c) show nearby nonoil and gas industry facilities appearing in the National Pollutant Release Inventory (NPRI). Colored triangles appearing in (b) and (d) indicate oil and gas wells, oil and gas batteries, gas plants, compressor stations, gas gathering systems and other associated upstream oil and gas facilities. Background satellite imagery source layer credits: Esri, DigitalGlobe, GeoEye, Earthstar Graphics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping Aerogrid, IGN,IGP,swisstopo, and the GIS User Community. Graphic: Johnson, et al., 2017 / Environmental Science & Technology

ABSTRACT: Airborne measurements of methane emissions from oil and gas infrastructure were completed over two regions of Alberta, Canada. These top-down measurements were directly compared with region-specific bottom-up inventories that utilized current industry-reported flaring and venting volumes (reported data) and quantitative estimates of unreported venting and fugitive sources. For the 50 × 50 km measurement region near Red Deer, characterized by natural gas and light oil production, measured methane fluxes were more than 17 times greater than that derived from directly reported data but consistent with our region-specific bottom-up inventory-based estimate. For the 60 × 60 km measurement region near Lloydminster, characterized by significant cold heavy oil production with sand (CHOPS), airborne measured methane fluxes were five times greater than directly reported emissions from venting and flaring and four times greater than our region-specific bottom up inventory-based estimate. Extended across Alberta, our results suggest that reported venting emissions in Alberta should be 2.5 ± 0.5 times higher, and total methane emissions from the upstream oil and gas sector (excluding mined oil sands) are likely at least 25–50% greater than current government estimates. Successful mitigation efforts in the Red Deer region will need to focus on the >90% of methane emissions currently unmeasured or unreported.

Comparisons of Airborne Measurements and Inventory Estimates of Methane Emissions in the Alberta Upstream Oil and Gas Sector