Global climate transformation stands as one of the most formidable challenges facing humanity, with methane playing a significant part in this ongoing process. Scientists have achieved a major breakthrough by investigating the repercussions of the colossal underwater eruption of the Hunga Tonga-Hunga Ha’apai volcano, which occurred in the southern Pacific Ocean in January 2022. As reported by Planet Today, citing the journal Nature Communications, the volcano not only ejected massive quantities of methane but also initiated a process that actively degrades this potent greenhouse gas. Researchers estimate that approximately 300 gigagrams of methane were introduced into the atmosphere during the eruption. Crucially, alongside this, vast amounts of volcanic ash and sea salt were propelled into the stratosphere. Experts determined that exposure to sunlight caused this mixture to generate reactive chlorine, which, in turn, breaks down atmospheric methane. This conclusion was drawn from satellite observations that detected unprecedented levels of formaldehyde—a byproduct of methane breakdown—within the volcanic plume. Maarten van Herpen of Acacia Impact Innovation BV noted that satellites tracked this cloud all the way to South America over a period of 10 days. He elaborated that because formaldehyde persists in the atmosphere for only a few hours, its sustained presence provided clear evidence that the volcano continuously eliminated methane for over a week. Calculations indicated that the volcanic trail was destroying roughly 900 megagrams of the greenhouse gas daily—an amount equivalent to the methane emitted daily by about two million cows.
It was already known that volcanoes release methane during eruptions. However, the realization that volcanic ash could act as a kind of atmospheric “scrubber” for this gas represents an entirely novel finding. Previously, researchers had only observed a comparable mechanism in the Atlantic, where dust from the Sahara Desert combined with sea salt to form aerosols under sunlight that fragmented methane. Yet, the conditions inherent in the stratosphere, where the Tonga volcano ejected its materials, are distinctly different. The significance of this discovery cannot be overstated. Methane contributes to roughly one-third of current global warming, possessing a heat-trapping capacity 80 times greater than carbon dioxide, although it breaks down in the atmosphere much faster—over approximately 10 years. Researchers suggest that if the degradation of methane could be artificially accelerated by leveraging this natural mechanism, humanity might gain an opportunity to apply an “emergency brake” and mitigate climate change. This finding, derived through sophisticated satellite instrumentation, necessitates a reevaluation of global methane calculations, as the impact of volcanic dust on its destruction had previously been disregarded. Moving forward, industry and the scientific community may seek to safely replicate this phenomenon to aid nature in combating the greenhouse effect.
About the Author
