Underwater eruptions form new islands — Surtsey appeared off Iceland in 1963 and is still being studied.

Phytoplankton populations have declined by about 40% since 1950, threatening the marine food chain.

Fact #5230 · Ocean

The Dead Sea is 10 times saltier than the ocean.

Fact #3396 · Ocean

More than 80% of the world's oceans remain unmapped and unexplored.

Fact #4284 · Ocean

The largest living structure on Earth is the Great Barrier Reef.

Fact #2632 · Ocean

The deep-sea environment is near freezing in temperature.

Fact #1419 · Ocean

The ocean contains structures larger than mountain ranges.

Fact #1805 · Ocean

Some whales communicate across vast distances underwater.

Fact #228 · Ocean

The Mariana Trench is the deepest known part of Earth's oceans.

Fact #109 · Ocean