Pumping CO2 through the seabed in \'world first\' environment test

We're all familiar with the relaxing sounds of the sea.

But the acoustics behind these bubbles aren't just soothing - they may be a crucial tool in the battle against climate change.

It's a possibility being tested in what is said to be the first experiment of its kind.

A group of scientists are monitoring controlled leaks of carbon dioxide under the North Sea, in the hope that, one day, the greenhouse gas can be captured and buried underwater for thousands of years - preventing harmful release into the atmosphere.

The idea is that the CO2 would be stored in depleted undersea oil and gas resevoirs.

The tests are designed to ensure the stored CO2 could never inadvertently leak into the ocean, undetected.

High-tech sensors will be deployed to try and detect the vibrations in these CO2 bubbles.

(SOUNDBITE) (English) NATIONAL OCEANOGRAPHY CENTRE, PROFESSOR DOUGLAS CONNELLY, SAYING: "We're going to put some CO2 two metres below the seabed.

We're going to bubble it out and then we're going to throw every toy in the box we have, every technological approach we have.

So remote-operated vehicles, undersea robots, in situ sensing technologies.

We're going to use chemistry, acoustics, everything that's current state of the art.

So we can actually look at detecting leakage and quantifying it." The researchers come from across the European Union, but also Shell.

The energy giant is one of the world's largest fossil fuel producers, a leading contributor to global CO2 emissions.

Environmental groups point to the fact a mere 5 percent of its budget is being invested in sustainable energy.

Underground storage for waste substances also has a checkered history, owing to long-term cost and safety concerns.