Global gas flaring volumes may be underestimated: comparisons with over a decade of industry reporting in Canada

Global gas flaring from the oil and gas industry was estimated to be 148 billion cubic meters in 2023, based on satellite observations from the Visible Infrared Imaging Radiometer Suite (VIIRS; World Bank, 2024). Both lit and unlit flares are sources of potent greenhouse gases and health hazards, making it a source requiring accurate global monitoring. The VIIRS instrument often forms the basis for gas flaring volumes, but our study reveals that these estimates are underestimated in Canada, and potentially elsewhere.

Comparing VIIRS flaring observations with industry reporting across Western Canada for 2012-2023, we found that industry reports ~2.3-times more gas flaring than estimated by satellite. This appears to be primarily the result of small/medium-sized flares going undetected (generally less than 350 m³/h, or 220 kg/h, assuming 90% methane content), but we also estimate that ~17% of industry-reported flaring was missed because of enclosed combustors, which do not have a flame visible to VIIRS. For flares that are detected by VIIRS, aggregate volume estimates agree within ~8% of industry reporting, although individual flares can be +/- an order of magnitude from industry reporting, similar to offshore findings from Brandt (2020).

If this issue of underestimated flaring volumes from VIIRS is limited to Canada, global gas flaring estimates would increase by only 1%, but Canada would be the 10^th most flaring country (up from 23^rd). However, if undetected flares are more widespread, global flaring could be much more deeply underestimated. VIIRS’s theoretical detection limits imply that smaller flares should be detected, implying other factors are impacting detection/quantification, such as VIIRS data filtering, flaring practices (e.g., daytime-only blowdown flaring), or persistent cloud cover.

 

References

Brandt AR. 2020. Accuracy of satellite-derived estimates of flaring volume for offshore oil and gas operations in nine countries. Environmental Research Communications 2(5). IOP Publishing. doi: 10.1088/2515-7620/ab8e17

World Bank. 2024. Global Gas Flaring Tracker Report. (June). Washington, DC. Available at https://www.worldbank.org/en/programs/gasflaringreduction/global-flaring-data. Accessed 2024 Jul 2.