A study published in Nature Geoscience in 2013 analyzed global methane (CH₄) sources and sinks over the past three decades (1980–2010). The research combined atmospheric measurements with data from chemical transport models, ecosystem models, and emission inventories to estimate methane emissions and sinks. The study found that data-driven approaches and ecosystem models overestimated total natural emissions. Three emission scenarios were developed to explain the observed variability in atmospheric methane levels since 1985. The stabilization of methane levels between 1999 and 2006 was attributed to decreasing-to-stable fossil fuel emissions and stable-to-increasing microbial emissions. The renewed increase in methane levels after 2006 was likely due to increased natural wetland and fossil fuel emissions, though the relative contribution of these sources remains uncertain. The study also examined the isotopic composition of methane to distinguish between biogenic, thermogenic, and pyrogenic sources. Biogenic sources, such as wetlands and rice paddies, had the most significant contribution to methane emissions. The primary sink for methane was oxidation by hydroxyl radicals (OH), accounting for about 90% of the global methane sink. Other sinks included methanotrophic bacteria and reactions with chlorine and atomic oxygen radicals. The study found that bottom-up estimates of methane emissions were higher than top-down estimates, suggesting that bottom-up models may overestimate total natural emissions. The global methane budget was analyzed using both top-down and bottom-up approaches, revealing significant uncertainties in emission estimates. The study highlighted the importance of improving wetland mapping, refining land surface models, and developing remote sensing data to better understand methane emissions. The study also discussed the challenges and opportunities in mitigating climate change. Methane has a relatively short atmospheric lifetime (about 10 years), making it a valuable target for short-term climate change mitigation strategies. However, the study emphasized the need for improved models of natural wetland and freshwater emissions, better monitoring of methane concentrations and fluxes, and new satellite missions to enhance our understanding of methane sources and sinks. The study concluded that a better quantification of the global methane budget, with regular updates, is essential for both addressing the challenges and opportunities associated with methane emissions.A study published in Nature Geoscience in 2013 analyzed global methane (CH₄) sources and sinks over the past three decades (1980–2010). The research combined atmospheric measurements with data from chemical transport models, ecosystem models, and emission inventories to estimate methane emissions and sinks. The study found that data-driven approaches and ecosystem models overestimated total natural emissions. Three emission scenarios were developed to explain the observed variability in atmospheric methane levels since 1985. The stabilization of methane levels between 1999 and 2006 was attributed to decreasing-to-stable fossil fuel emissions and stable-to-increasing microbial emissions. The renewed increase in methane levels after 2006 was likely due to increased natural wetland and fossil fuel emissions, though the relative contribution of these sources remains uncertain. The study also examined the isotopic composition of methane to distinguish between biogenic, thermogenic, and pyrogenic sources. Biogenic sources, such as wetlands and rice paddies, had the most significant contribution to methane emissions. The primary sink for methane was oxidation by hydroxyl radicals (OH), accounting for about 90% of the global methane sink. Other sinks included methanotrophic bacteria and reactions with chlorine and atomic oxygen radicals. The study found that bottom-up estimates of methane emissions were higher than top-down estimates, suggesting that bottom-up models may overestimate total natural emissions. The global methane budget was analyzed using both top-down and bottom-up approaches, revealing significant uncertainties in emission estimates. The study highlighted the importance of improving wetland mapping, refining land surface models, and developing remote sensing data to better understand methane emissions. The study also discussed the challenges and opportunities in mitigating climate change. Methane has a relatively short atmospheric lifetime (about 10 years), making it a valuable target for short-term climate change mitigation strategies. However, the study emphasized the need for improved models of natural wetland and freshwater emissions, better monitoring of methane concentrations and fluxes, and new satellite missions to enhance our understanding of methane sources and sinks. The study concluded that a better quantification of the global methane budget, with regular updates, is essential for both addressing the challenges and opportunities associated with methane emissions.