How does ocean acidification impact marine life?

Water becomes more acidic as it absorbs carbon dioxide, which is bad news for many of our aquatic cousins.


Asked by: Karen Drake, Chelmsford

There’ll be many losers, and perhaps some winners among marine life as the oceans absorb humanity’s CO2 and pH falls. An eight-year study involving 250 scientists recently revealed a complex picture of changes rippling through food webs.

Organisms with carbonate exoskeletons – like starfish, mussels and swimming snails called sea butterflies – tend to suffer because their shells become unstable. Young animals are especially at risk; cod larvae are twice as likely to die at lower pH.

Barnacles and a few other robust animals can adapt but may still suffer from the combined impacts of other threats, like plastic pollution and rising temperatures.

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