Methane emission dynamics from a Danish landfill: The effect of changes in barometric pressure. (1st February 2022)

• Record Type: Journal Article
• Authors: Kissas, K.; Ibrom, A.; Kjeldsen, P.; Scheutz, C.
• Is Part Of: Waste management. Volume 138(2022)
• Page Start: 234
• Page End: 242
• Publication Date: 2022-02-01
• Subjects: Methane quantification -- Rate of change in pressure -- Tracer dispersion method -- Eddy covariance flux measurement -- Inter-comparison; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2021.11.043
• Languages: English
• ISSNs: 0956-053X

Abstract

Graphical abstract: Highlights: Landfill CH4 emissions are inversely correlated with the rate of change in pressure. Short-term effect from pressure outweigh the effect of temperature and wind speed. Large seasonal but not any diurnal variability was observed in CH4 emissions. Results from two independent CH4 quantification techniques were strongly correlated. Abstract: This study investigates temporal variability on landfill methane (CH4 ) emissions from an old abandoned Danish landfill, caused by the rate of changes in barometric pressure. Two different emission quantification techniques, namely the dynamic tracer dispersion method (TDM) and the eddy covariance method (EC), were applied simultaneously and their results compared. The results showed a large spatial and temporal CH4 emission variation ranging from 0 to 100 kg h −1 and 0 to 12 μmol m −2 s −1, respectively. Landfill CH4 emissions dynamics were influenced by two environmental factors: the rate of change in barometric pressure (a strong negative correlation) and wind speed (a weak positive correlation). The relationship between CH4 emissions and the rate of change in barometric pressure was more complicated than a linear one, thereby making it difficult to estimate accurately annual CH4 emissions from a landfill based on discrete measurements. Furthermore, the results did not show any clear relationship between CH4 emissions and ambient temperature. Large seasonal variations were identified by the two methods, whereas no diurnal variability was observed throughout the investigated period. CH4 fluxes measured with the EC method were strongly correlated with emissions from the TDM method, even though no direct relationship could be established, due to the different sampling ranges of the two methods and the spatial heterogeneity of CH4 emissions.