Evaluating ethane and methane emissions associated with the development of oil and natural gas extraction in North America

Using time series of C₂H₆ total columns derived from ground-based Fourier transform infrared (FTIR) observations made at five selected Network for the Detection of Atmospheric Composition Change sites, we characterize the recent C₂H₆ evolution and determine growth rates of ~5% yr⁻¹ at mid-latitudes and of ~3% yr⁻¹ at remote sites.

Results from CAM-chem simulations with the Hemispheric Transport of Air Pollutants, Phase II bottom-up inventory for anthropogenic emissions are found to greatly underestimate the current C₂H₆ abundances. Doubling global emissions is required to reconcile the simulations and the observations prior to 2009. We further estimate that North American anthropogenic C₂H₆ emissions have increased from 1.6 Tg yr⁻¹ in 2008 to 2.8 Tg yr⁻¹ in 2014, i.e. by 75% over these six years.