PBS Anywhere

Providing Support for PBS.org

Under H2O

When a Volcano Erupts Underwater

6:51

On the southeast coast of the big island of Hawaii, lava flowing from the Kilauea crater collides with the Pacific Ocean. As new lava emerges, it quickly cools, forming billowy, round shapes called pillow lava. The constant accumulation of new rock results in frequent collapse and avalanche on the reef slope -- an accelerated cycle of creation and destruction.

Episodes of Under H2O9

Under H2O

Damselfish in Distress

Male damselfish try in vain to protect a brood of eggs from a saddle wrasse assault.

5:38

Under H2O

The Power of Waves

The UnderH2O crew ventures out into Waimea Bay to explore the science of big waves.

7:27

Under H2O

Into the Mangrove Forest

The mangrove forest is a place of amazement both above and below the waterline.

5:45

See all Episodes