Microbes are ubiquitous, found across the Earth, in the atmosphere, and in water bodies. They play a crucial role in the cycling of elements on our planet. Although invisible to the naked eye and observable only through specialized microscopes, these tiny organisms have significant impact on our lives.
For instance, some microbes produce valuable substances, such as antibiotics and other products. Additionally, certain types of microbes are capable of generating methane, one of the greenhouse gases contributing to climate change today.
A research group from the University of Colorado in Boulder, USA, conducted a study to investigate how much methane emitted by microbes affects global warming. Understanding the sources of methane is essential for developing effective mitigation strategies. Their findings, published in the Proceedings of the National Academy of Sciences on October 21, 2024, revealed that these microorganisms significantly increase methane levels in the atmosphere.
Why Methane?
Researchers focus on methane because it is one of the most potent greenhouse gases, with a warming potential 80 times greater than that of carbon dioxide. Since pre-industrial times, methane’s atmospheric concentration has tripled. The good news is that methane decomposes within about a decade, unlike carbon dioxide, which takes approximately a century to break down. Therefore, addressing methane emissions presents a promising opportunity to mitigate the climate crisis; understanding and regulating its sources can help slow the rate of global warming.
Microbial Contributions
Scientists could analyze the air to determine the proportions of various gases, including carbon dioxide and methane. By examining the carbon isotopes in methane samples, researchers can trace its origin. For instance, methane derived from fossil fuels tends to have more carbon-13, while methane from microbial sources contains less.
Since 2007, atmospheric methane levels have been rapidly rising, peaking in 2020. The dramatic increase in methane emissions between 2020 and 2022 has been notably attributed to microbes. This raises an important question: What are the sources of these microbes? Several potential sources include wetlands, livestock, and landfills, where microbes thrive and produce methane.
However, it remains unclear whether the methane emissions originate from microbes in wetlands, landfills, livestock, or from human activities. This is an area of ongoing research for scientists.
