Ocean Acidification: Chemistry and Coral Reef Loss

The Family Chemistry Project

Hawaii — something wasn't right

A personal story connecting to ocean acidification and calcium carbonate (CaCO₃)

THE SETUP

The setup

I went to Hawaii to surf and scuba dive. The water was warm and clear, the reef was bright with color — fish everywhere, it looked like a nature documentary. I was completely in my own world.

Warm, clear ocean water

Colorful vibrant reef below

Fish everywhere — felt like paradise

HEALTHY REEF

BLEACHED REEF

The incident

Grey and crumbling — almost like concrete

No color, no life

Looked like a graveyard underwater

Why does it look like this?

THE BRIDGE

Coral isn't just a rock

Coral is actually a living animal. It builds a skeleton from calcium carbonate (CaCO₃) — the same compound in seashells and limestone. When coral dies it loses all color, hardens, and turns grey. That's exactly what I cut my foot on. But why is it dying?

Living organism — not a plant or rock

Skeleton made of calcium carbonate (CaCO₃)

Dies → loses color → hardens → turns grey

Soft tissue (polyp)

CaCO₃ skeleton

THE CHEMISTRY

Ocean acidification

CO₂ + H₂O

H₂CO₃

lowers pH

dissolves CaCO₃

coral breaks down

→

CO₂ from our atmosphere dissolves into the ocean, forming carbonic acid (H₂CO₃). That acid lowers the ocean's pH.

That acid dissolves calcium carbonate — the exact material coral is built from. The reef isn't just dying, it's being eaten away by acid from our own atmosphere.

The Family Chemistry Project

This isn't just a Hawaii problem

50%

of the world's coral reefs have died since the 1950s

30%

more acidic — ocean pH dropped from 8.2 to 8.1

25%

of all marine life depends on coral reefs

I didn't think about any of this when I was in Hawaii. I just thought I cut my foot on a rock. But that grey crumbling reef was a chemical warning sign — and now I can actually read it.