Japanese earthquake recorded from sea floor

Listening stations on the seabed all over the world are streaming sound in real time to websites that anyone can access, allowing people to hear everything from male humpback whales singing off Hawaii, to last year's Japanese earthquake.

Conscious of security, the US Navy has brokered a deal with scientists in the north Pacific which allows the navy to delete any sounds of US or Canadian military shipping before the audio is sent out across the internet.

It now wants to do similar deals with other scientists around the world, but some experts say that is both improbable, and in this new age of internet accessibility, unreasonable.

This is the sound of the Japanese earthquake that triggered the devastating tsunami in March 2011. It was recorded by sea floor observatories off the coast of Japan.

The sound has been sped up to make it audible to the human ear.