Unveiling the impact of soil methane sink on atmospheric methane concentrations in 2020

Abstract In 2020, anthropogenic methane (CH 4 ) emissions decreased due to COVID‐19 containment policies, but there was a substantial increase in the concentration of atmospheric CH 4 . Previous research suggested that this abnormal increase was linked to higher wetland CH 4 emissions and a decrease in the atmospheric CH 4 sink. However, the impact of changes in the soil CH 4 sink remained unknown. To address this, we utilized a process‐based model to quantify alterations in the soil CH 4 sink of terrestrial ecosystems between 2019 and 2020. By implementing the model with various datasets, we consistently observed an increase in the global soil CH 4 sink, reaching up to 0.35 ± 0.06 Tg in 2020 compared to 2019. This increase was primarily attributed to warmer soil temperatures in northern high latitudes. Our results emphasize the importance of considering the CH 4 sink in terrestrial ecosystems, as neglecting this component can lead to an underestimation of both emission increases and reductions in atmospheric CH 4 sink capacity. Furthermore, these findings highlight the potential role of increased soil warmth in terrestrial ecosystems in slowing the growth of CH 4 concentrations in the atmosphere.