Quantifying methane emissions from UK Landfills Using Unmanned Aerial Vehicles

Methane (CH₄) is a potent greenhouse gas, with a global warming potential 27.2 to 29.8 times greater than carbon dioxide (CO₂) over a 100-year timescale. Accurate quantification of methane emissions is crucial for developing effective climate change mitigation strategies and meeting international agreements on greenhouse gas reduction. However, significant uncertainties remain in estimating methane emissions, particularly from anthropogenic sources such as landfills, due to spatial heterogeneity and complex atmospheric interactions.

Landfills are known as significant contributors to anthropogenic methane emissions. In recent years, the use of unmanned aerial vehicles (UAVs) equipped with high-precision methane sensors has developed into a promising approach for quantifying these emissions. This method offers advantages such as improved spatial coverage, reduced operational costs and dynamic monitoring. The field of emissions quantification by UAV survey has rapidly expanded over the past decade, with a growing international academic community refining and validating methods, and an emerging commercial sector driving technological advancements.

Our study focuses on quantifying methane emissions from three UK landfills in 2024/25 using drone-based spatial sampling of in situ gas concentrations, wind speed and direction. We apply and compare different mass balance methods with varying approaches to spatial interpolation, to test the sensitivity of emission quantification to the selected approach. This analysis aims to assess the strengths and limitations of each method when applied to landfill environments. Additionally, we conduct an error analysis, examining the main sources of uncertainty such as wind measurements and background methane concentrations. 

By addressing these challenges, our research contributes to improving the accuracy and robustness of drone-based methane quantification for landfill applications (and similar local scale sources). This work supports the development of methods for measuring emissions directly, which is crucial for setting emission reduction targets and improving national greenhouse gas inventories in waste management.