Ocean Acidification Simulator
See how dissolved CO₂ lowers ocean pH and threatens shell-forming animals.
The chemistry: CO₂ + H₂O ⇌ H₂CO₃ ⇌ H+ + HCO₃−, and the extra H+ reacts with carbonate: H+ + CO₃2− → HCO₃−. Shell builders need CO₃2− to make CaCO₃.
Ocean pH8.20
H⁺ vs pre-industrial+0%
Carbonate ion240 µmol/kg
Shell-building (Ω aragonite)3.4
Coral and shell growth100%
What you can learn
- CO₂ dissolves in seawater to form carbonic acid, releasing H⁺.
- More H⁺ means lower pH and fewer carbonate ions.
- Shell and coral builders need carbonate ions to make calcium carbonate.
Frequently asked questions
Why does CO₂ make the ocean more acidic?
CO₂ + H₂O forms carbonic acid, which releases hydrogen ions and lowers the pH.
How does this harm shell-building animals?
The extra hydrogen ions react with carbonate ions, leaving fewer for animals to build shells, which can even dissolve.