How does ocean acidification affect coral reefs?

Ocean acidification makes it harder for coral reefs to grow and stay strong.

Imagine your favorite building block toy, like LEGOs. Corals use something called calcium carbonate to build their homes, just like you use blocks to make a tower. But when the ocean gets more acidic, it's like someone is sneaking in and taking some of those blocks away before you can stack them.

What makes the ocean more acidic?

The ocean is like a big bathtub that absorbs carbon dioxide from the air, kind of like how your bathwater gets warmer when you leave the tap on. When carbon dioxide mixes with water, it makes the ocean slightly more acidic, just like adding lemon juice to water makes it sour.

How does this hurt coral?

Coral needs a lot of calcium carbonate to build and repair its structure. If there's not enough around because the ocean is too acidic, the coral can't grow as well, it’s like trying to build a tower with only half the blocks you need. Over time, this makes coral reefs weaker and more likely to break apart.

So, the ocean being more acidic is like giving the coral a harder challenge to stay strong and healthy.

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Examples

  1. A coral reef is like a city for sea animals. When the ocean gets more acidic, it's harder for corals to build their homes.
  2. Imagine if your building materials turned weak because of a chemical change in the air you breathe.
  3. Fish and other creatures rely on strong coral structures, when they weaken, the whole ecosystem suffers.

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