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A New Zealand researcher has set a record for travelling by ship across the top of the world on the Arctic ice cap, using the boat on which Sir Peter Blake died.

Grant Redvers, 34, of Wellington, is expedition chief of the voyage of the Tara, which is about to emerge from the Arctic ice after passing within 160km of the North Pole while deliberately trapped in an ice floe.

Mr Redvers said on the Tara expedition's website that he first became aware of the schooner when it was owned by Sir Peter and known as Seamaster.

It had been built with a thick, round, aluminium hull, designed to rise up when caught between plates of ice like an olive stone crushed between a finger and thumb.

Sir Peter was murdered by "pirates" - thieves who robbed visiting vessels - while on board the ship on the Amazon in 2001, after which it was bought by Etienne Bourgois, head of the French fashion company Agnes B.

It was deployed to the Arctic last year and deliberately trapped in an ice floe north of Russia to prove a theory of transpolar drift, with funding from the European Union and Mr Redvers acting as chief of the expedition, with eight French and Russian crew, The Times newspaper reported.

Mr Redvers, who has a masters degree in environmental science, spent three seasons as a scientific technician at Scott Base, and participated in earlier Tara expeditions ton the Antarctic Peninsula in 2005, to South Georgia in 2005 and 2006 and to Patagonia in 2006.

For the past 15 months the ship has ridden high and dry on the ice pack, as if sailing on a sea of snow. In fact the double-masted schooner and its crew of increasingly smelly scientists and engineers, has been traversing the ice-cap.

The Tara has travelled farther north than any ship before her, to 88:32deg latitude, 160km shy of the pole, and now it is trapped in an ice floe.

Now it is approaching the far side of the Arctic ice sheet, about to be spat out into the Fram Strait between Greenland and Svalbard, thousands of kilometres from where it started.

It proves the theory of Norwegian explorer Fridtjof Nansen, who found a vessel in southwest Greenland three years after it was trapped off the coast of New Siberia: he said there was a transpolar drift in the sea-ice.

Nansen ran his own re-inforced vessel, the Fram, into the ice in 1893 and took three years to drift across the Arctic.

Mr Redvers told The Times by satellite phone the Tara was expected to take two years, but the conveyor belt of the Arctic appeared to have been accelerated. There have been a number of adventures: days after being pushed up out of the ice, the ice sheet was broken up in a storm and equipment the crew on the ice had to be retrieved from many different ice floes.

There was another scare with a pressure ridge caused by colliding plates of ice advancing towards the boat.

"It was like a frozen wave, moving in super-slow motion - about a centimetre a second," Mr Redvers told The Times. "At one stage we attacked it with picks and chainsaws, but there was no way we could stop it.

"It leant over the boat, then suddenly it stopped by itself and we were released from the pinch," Mr Redvers said.

There were regular encounters with polar bears, but Mr Redvers said leaving the ice pack will be one of the most perilous moments of the voyage: the ship could be capsized by colliding fragments of ice floe.

"We're prepared to leave the ship if we have to," Mr Redvers said.

- NZPA