Increasing carbon dioxide emissions could leave species such as coral and sea urchins struggling to survive by the end of the century because they are making the oceans more acidic.

Research by British scientists has found that rising carbon emissions will alter the biodiversity of the seas profoundly. Greater concentrations of carbon dioxide in the atmosphere mean that more of the gas becomes dissolved in seawater, increasing its acidity.

The research team was the first to use natural underwater carbon dioxide vents to assess how acidity caused by the gas influences sea life. “Our field studies provide a window on the future of the oceans in a high CO2 world,” Dr Hall-Spencer from the University of Plymouth.

“We show the dramatic ecological consequences of ocean acidification including the removal of corals, snails and sea urchins and the proliferation of invasive alien algae. Our observations verify concerns, based on laboratory experiments and model predictions, that marine food webs will be severely disrupted and major ecological tipping-points are likely if human CO2 emissions continue unabated.”