Title: Unraveling the Mystery of Methane Emissions: A New Study by Naveen Chandra and His Team
For the past three years, researcher Naveen Chandra has been dedicated to simulating the Earth’s atmosphere on a supercomputer at the Research Institute for Global Change in Japan. His focus has been on recreating the last 50 years of the Earth’s atmosphere, with a specific interest in the concentration of methane and its sources.
Methane is the second most prevalent anthropogenic greenhouse gas, with a global warming potential 28 times greater than carbon dioxide (CO2) over a century. In recent years, there has been growing concern about methane’s impact on climate change, leading to the launch of the ‘Global Methane Pledge’ at the U.N. climate talks in 2021.
Dr. Chandra and his team recently reported that microbes are the largest source of methane emissions, rather than fossil fuel combustion. These microbes, called methanogens, produce methane through biogenic processes, while thermogenic methane is released through the extraction of fossil fuels from deep within the Earth’s crust.
To better understand methane emissions, Dr. Chandra and his team collected data from 12 monitoring sites worldwide, tracking atmospheric parameters since the 1990s. They then sorted the methane isotope data by year and ran it through a program they developed to recreate the atmosphere from 1980 to 2020 on a supercomputer.
Their findings revealed some discrepancies with two emissions inventories, EDGAR and GAINS, particularly in methane emissions from oil and natural gas exploration. The study’s authors suggest that an increase in cattle-rearing in Latin America and more emissions from waste in South and Southeast Asia, Latin America, and Africa, as well as an increase in the number of wetlands worldwide, could be potential reasons for these discrepancies.
According to Dr. Patra, the study’s lead author, combining the numbers for all biogenic and thermogenic isotopes should match the total emissions in a year. However, when they ran their atmosphere models with this data, the year-wise total methane emissions overshot the total production. They found that microbes were producing more methane than fossil fuels.
The study highlights the need for local data, specifically from wetlands and rice fields, to gain a better understanding of methane emissions sources. According to Dr. Patra, “If you want to reduce methane, anthropogenic activity should be first controlled. And we can clearly outline what is anthropogenic here. Waste and landfills, rice fields, enteric fermentation, oil and gas, and coal.”
This new study sheds light on the complex nature of methane emissions and the need for further research to better understand its sources and impact on climate change. As policymakers work to address global warming, understanding and reducing methane emissions will be crucial in mitigating its effects.