Asked by: Mark Cooper, Manchester
Capturing carbon dioxide (CO2) to stop it boosting global warming seems a good idea, but raises the problem of where to store the stuff. One low-cost solution is simply to pump it into the deep ocean, but CO2 is toxic to marine life and would also combine with the seawater to produce an acid, which would pose unknown environmental risks. Underground or sub-seabed storage are thought be less risky options.
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