Source Category Attribution of Methane Emissions in Calgary Using Positive Matrix Factorization
Year: 2026
Type: article
Abstract: Cities emit methane (CH 4 ) and have a role to play in mitigating the climate impacts of their emissions. Research suggests that CH 4 emissions from most North American cities have large contributions from natural gas distribution and end use. In this work, we examine trace gas measurements from a central air monitoring station in Calgary, Alberta, Canada to attribute the city’s CH 4 emissions to major source categories. Using positive matrix factorization (PMF), we identified four primary CH 4 emissions source categories: natural gas─fugitives, natural gas─incomplete combustion, waste/biogenic, and petroleum product processing. Results from PMF modeling indicate that the bulk of CH 4 emissions in Calgary are from natural gas fugitives and incomplete combustion (81% ± 35%). This is much higher than the proportion derived from available bottom-up emissions inventories. The CH 4 emissions from natural gas sources increase in winter and may be related to increased natural gas use for space heating. Emissions from waste/biogenic sources were the next largest contributor, which doubled in warmer months, consistent with temperature-driven microbial activity. Though relatively small, CH 4 emissions from petroleum product processing are non-negligible and consistent. Overall, these findings underscore the need for targeted mitigation strategies focused on the natural gas supply chain, while also highlighting the influence of seasonal dynamics on urban CH 4 emissions.
Source: ACS ES&T Air
Institution: University of Calgary
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
Funder: Government of Canada
OpenAlex ID: W7124445681