What effect does carbon capture have on atmospheric oxygen?

Asked by: Alan Thomas, Shepperton

The capture and storage of carbon dioxide directly from factory chimneys and other polluting sources has been suggested by some scientists as a solution to the problem of global warming, and much research is now being concentrated in this area. If this carbon dioxide entered the atmosphere, the oxygen would eventually be released as a part of the global carbon cycle, involving the weathering of rocks, dissolution in the oceans, and absorption by plants, which then release oxygen in the process of photosynthesis.

The amount of oxygen that would be lost in the process of carbon dioxide capture would be around four billion tonnes per annum, according to figures published by the Oak Ridge National Laboratory. Luckily, this is only 0.0005 per cent of the quadrillion (that’s 1 followed by 15 zeros) tonnes of oxygen found in the Earth’s atmosphere.

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