After years of research – and with the fate of planet Earth hanging in the balance – the Nasa scientist who helped to put a robot on Mars has finally completed work on a device that can measure how fast Greenland’s ice-cap is melting.

The bright yellow probe is considered the pinnacle of environmental research technology, and has been made to endure sub-zero temperatures and ocean currents as powerful as those under Niagara Falls. It can even withstand being trapped beneath a mile-thick slab of ice.

Nevertheless, Nasa is reluctant to take all the credit. Why? Because the device in question is none other than a rubber ducky, the kind beloved by toddlers around the world at bathtime. And unlike Nasa’s multibillion-dollar inventions, this one is more suited to the current economic climate – the ducks cost $2 each.

The idea to use bathtub toys for ice-cap research came from Alberto Behar, a rocket scientist and world authority on space robotics who works at the Nasa Jet Propulsion Laboratory near Los Angeles.

For years he had been desperate to find out more about exactly how and why the ice-caps are melting in Greenland. His research has so far focused on the Jakobshavn Glacier, probably the source of the iceberg that sank the Titanicin 1912. “It’s a beautiful place to visit,” he said in a recent interview.

“You can watch these icebergs continuously march across and fall into the ocean. [But] it’s not understood what causes the glaciers themselves to ‘surge’ in the summer.”

When glaciers surge, they move at up to 100 times their usual speed. Scientists believe that surging could be caused by water from melting ice on the top of a glacier flowing into tubular holes and eventually reaching the base, where it acts as a lubricant, speeding the movement of the glacier towards the coast.

Cue the rubber ducks. In August, Dr Behar flew to the Jakobshavn Glacier and landed near one of the tubular holes, known as “moulins”. Into one of the moulins he dropped 90 ducks, each labelled with the words “Science Experiment” and “Reward” in three languages along with an e-mail address. If the ducks are ever found, they will tell Dr Behar exactly what happens to the melted water from the glacier, allowing him to predict exactly how a catastrophic ice-cap melt would affect ocean levels. He hopes that they’ll be picked up by a fishing vessel about 30 miles (48km) away in Disco Bay, near Ilulissat.

Dr Behar also dropped a football-sized probe that was equipped with a GPS transmitter, a temperature gauge and an “accelerometer” to provide even more detailed information about the innards of the glacier.

His research is arguably crucial to the survival of modern civilisation. Glacier ice represents the largest reservoir of fresh water on Earth, and if Greenland’s 2.2 million square miles of ice ever melted completely, sea levels would rise by an estimated 24ft (7.3m), destroying cities such as London and New York.

The Nasa scientist’s inspiration originally came from a news story about a shipping consignment of 28,200 rubber duckies and other bathtub toys that were lost at sea in 1992. Because the duckies were stamped with a unique manufacturing code, they ended up being used by scientists to document previously unknown ocean currents. In 2003 one of the toys turned up in Scotland.

So far Dr Behar’s ducks have not saved the world, but he remained confident. “It may take some time until somebody actually finds [them] and decides to send us an e-mail,” he said. “These are places that are quite remote. There aren’t people walking around.”

Ducking the issue

— The first rubber ducks are believed to have been produced in the 1880s. They were made of hard rubber – the squeak was a late addition

— In January 1992 20,000 rubber ducks and an assortment of other plastic animals fell off a boat in the Pacific. Since this accident scientists have started using rubber ducks to chart tidal patterns and water currents

— In July 2006 20,000 rubber ducks were released into the Thames at Battersea Park for a race. The tide took a large percentage of the ducks off course but the winner completed the race in half an hour

— In 2001 The Sun claimed that the Queen had a rubber duck with a crown in her bathtub. Sales of rubber ducks in Britain went up by 80 per cent

Source: Times Archive

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