Chinese scientists discover new geochemical "switch” that regulates global climate

Researchers at the Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, have published a study revealing how changes in oceanic sulphate concentrations regulate the way methane is consumed on the seafloor. This mechanism has been described as a “geochemical switch” that influences global climate, according to China Daily, a partner of TV BRICS.

The study shows that even slight variations in oceanic sulphate levels can alter methane metabolism pathways: when sulphate is abundant, microbes efficiently consume methane through sulphate reduction, producing alkaline substances that help mitigate ocean acidification. 

Conversely, when sulphate is scarce, methane cannot be effectively broken down, leading to substantial carbon dioxide release and exacerbating climate change.

Analysing a palaeoclimate event from 56 million years ago, the researchers found that Arctic seawater then contained only one-third of modern sulphate levels. This triggered rapid methane combustion and carbon dioxide release, turning the Arctic from a “carbon sink” into a “carbon source,” a pattern that bears similarities to current Arctic warming trends.

As Arctic waters continue to warm and their chemical environment changes, this mechanism could be reactivated. The study highlights the need to closely monitor the interaction between methane emissions and climate change, offering fresh insights into the global carbon cycle.

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