Ocean Acidification and its Effects

Ocean Acidification

• Ocean acidification occurs when CO2 gas dissolves in the ocean and chemically reacts with seawater.
• Despite its name, the ocean does not become acidic, but remains alkaline, with a pH closer to the acidic end of the scale.
• The reaction between CO2 and seawater forms an unstable molecule called carbonic acid, which becomes stable by releasing a hydrogen ion and becoming bicarbonate.
• The increase in hydrogen ions reduces the pH of the water, making it closer to acidity.
• The production of hydrogen ions affects marine organisms, such as corals and mollusks, that use calcium carbonate to build strong structures.
• Calcium carbonate is formed from calcium and carbonate, which is affected by the increase in hydrogen ions.
• Hydrogen ions bind more easily with carbonate than with calcium, causing corals to miss out on needed calcium, leading to slowed growth.
• While the oceans are still safe for humans, the increase in hydrogen ions can make it difficult for many marine organisms to survive.

Ocean Acidification

• Ocean acidification occurs when CO2 dissolves in seawater, triggering a chemical reaction.
• Despite the name, the ocean remains alkaline, but its pH shifts closer to the acidic end of the scale.
• The reaction between CO2 and seawater forms carbonic acid, which breaks down into bicarbonate and releases a hydrogen ion.
• The increased hydrogen ions reduce the pH of the water, making it more acidic.

Impact on Marine Organisms

• The increase in hydrogen ions affects marine organisms like corals and mollusks that use calcium carbonate to build strong structures.
• Calcium carbonate formation is disrupted by the increased hydrogen ions, which bind more easily with carbonate than calcium.
• This causes corals to miss out on needed calcium, leading to slowed growth.
• The increased hydrogen ions can make it difficult for many marine organisms to survive.