Comment on ‘Estimating methane emissions from manure: a suitable case for treatment?’

Ward et al (2024 Environ. Res. 1 025003) recently published a paper in this journal (Ward et al 2024 Environ. Res. 1 025003) asserting that methane emissions from manure management in the United Kingdom Inventory of Greenhouse Gas emissions could be under-estimated by a factor of four to five. This was based on extrapolation of measurements from two farms located in the south-west of England where manure management is purposely set-up to encourage methane release and capture, for use as a fuel source. We argue that methane thus extracted cannot be compared with the quantities emitted to the atmosphere on a typical farm which is what the national Inventory seeks to estimate, and show that existing Inventory calculations are consistent with wider literature and typical management practices in the United Kingdom.