Ocean Acidification and Marine Life — Passage and Quiz

Did you know the ocean absorbs about 30% of the carbon dioxide (CO₂) humans release into the atmosphere? While this helps slow climate change, it comes at a cost: ocean acidification.

When CO₂ dissolves in seawater, it triggers a chemical reaction that forms carbonic acid. Over time, this acid lowers the ocean’s pH, making the water more acidic. Since the Industrial Revolution, ocean acidity has increased by 30%—faster than any change in 50 million years!

This shift harms marine life. For example, shellfish, corals, and plankton rely on calcium carbonate to build their shells and skeletons. Acidic water dissolves this mineral, making it harder for them to grow or survive. Coral reefs, which are home to 25% of marine species, bleach and crumble in acidic conditions. Even fish struggle, as acidity disrupts their ability to detect predators or navigate.

The biggest cause of acidification is burning fossil fuels like coal and oil, which releases excess CO₂. Deforestation also plays a role, as fewer trees mean less CO₂ absorbed from the air.

The good news? We can slow acidification by switching to renewable energy (solar, wind), protecting coastal ecosystems like mangroves, and reducing plastic waste (which harms marine life already stressed by acidity). Small actions, like biking instead of driving, add up!

Fun fact: Clownfish (like Nemo!) lose their sense of smell in acidic water, making it harder to find their way home!