Fact brief - Do volcanoes emit more CO2 than humans?

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Do volcanoes emit more CO2 than humans?

Volcanoes release CO₂, but the amount is minimal compared to human-caused emissions.

According to the U.S. Geological Survey, volcanoes emit around 180-440 million tons of CO₂ annually. In contrast, human activities, primarily burning fossil fuels, emitted 41.5 billion tons of CO₂ in 2022—over 100 times more.

Volcanoes are part of the Earth’s slow carbon cycle, where carbon is gradually recycled between the Earth’s mantle and atmosphere over millions of years. Volcanic CO₂ is eventually reabsorbed by the weathering of rocks and ocean absorption, keeping the carbon cycle in balance over long timeframes.

Human activity, however, is releasing carbon at a rate far beyond what the natural carbon cycle can handle, overwhelming the Earth’s ability to balance CO₂ levels. While volcanic CO₂ emissions have been stable for millions of years, human-caused emissions have rapidly accelerated since the Industrial Revolution, making human activity the dominant driver of rising atmospheric CO₂.

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Sources

USGS Volcanic gases can be harmful to health, vegetation and infrastructure

Our World in Data CO2 emissions

NASA The Carbon Cycle

USGS Volcano Watch — Which produces more CO2, volcanic or human activity?

About fact briefs published on Gigafact

Fact briefs are short, credibly sourced summaries that offer “yes/no” answers in response to claims found online. They rely on publicly available, often primary source data and documents. Fact briefs are created by contributors to Gigafact — a nonprofit project looking to expand participation in fact-checking and protect the democratic process. See all of our published fact briefs here.

Posted by Guest Author on Saturday, 26 October, 2024

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