Temperature and rainfall variations contribute to 13% of methane emissions at one of the world’s largest landfill sites, a recent study has discovered. The researchers indicate that their models demonstrate that in an evolving climate with more severe weather, methane emissions from landfills will rise even further, intensifying global warming.
Methane makes up roughly 16% of anthropogenic greenhouse gas emissions, with studies suggesting that this gas has accounted for 30% of global warming since the onset of the industrial era. Landfills represent 19% of human-related methane emissions, positioning these waste sites as the third-largest contributor of methane after agriculture and the fossil fuel industry. In some urban areas, the share of landfills in total methane emissions can be even more significant. A 2022 research indicated that a single landfill in Buenos Aires was responsible for half of the city’s methane emissions.
Examining the Sudokwon Landfill Site in South Korea – one of Asia’s largest – researchers from Seoul National University modified a commonly used machine-learning model to account for the local environment and estimate methane emissions at specific site locations. By considering the composition and organic degradability of waste, along with factors like waste composition, particle size, temperature, moisture, and pH, they demonstrated that their climate-sensitive modeling enhanced methane emission predictions compared to earlier models.
The scientists trained their machine-learning model using field data from the Sudokwon site between 2005 and 2021 before evaluating an idealized scenario with a constant waste composition and volume. Their findings indicated that temperature fluctuations accounted for around 6% of methane emissions, whereas variations in precipitation accounted for just over 7%.
The researchers assert that adjusting emissions calculations to be more responsive to climate variables and tailored to specific sites could aid in developing effective mitigation strategies, as well as customizing them according to landfill type and weather conditions.