PLYMOUTH polar explorer Antony Jinman says melting ice means he may have to do some swimming as he embarks on his quest to ski to the North Pole.

The expedition, Antony's toughest yet, will mean spending about two months on the dangerous sea ice of the Arctic, with little possibility of rescue and temperatures as low as minus 50 Centigrade.

Before leaving Plymouth yesterday, Antony inspected recent satellite images of the Arctic, which show the sea ice split by channels of open water.

He said: "The sea ice this year is once again in quite a bad state. It will create difficulties but we're able to raft together the sledges, and I can swim across.

"It's good fun. I use an all-in-one dry suit. We tried it last year and it works fine."

Antony is part of an expedition that will walk 480 miles from Cape Discovery to the North Pole over the next 10 weeks.

The first part of his journey was a flight from London to Ottawa, Canada, yesterday morning. From there he will transfer by internal flight to Cape Discovery, where he will meet his expedition companions, Eric Larsen and Darcy St Laurent.

Antony and his team raised more than £100,000 to make the expedition possible, and have teamed up with the University of Plymouth to carry out research into the effects of climate change on the Polar Ice Cap.

Using coring devices, they will manually 'drill' into the frozen sea surface to collect the bottom few centimetres of sea ice at many points along their route, aiming to gather traces of an algae known to hold key information about historical climate conditions. The ice will then be gently melted and filtered to collect the algae and its 'chemical fingerprint' for later analysis in laboratories in Plymouth.

Little data has been gathered on the Polar Ice Cap because of the difficulty of working in such an inhospitable environment.

Professor Simon Belt, of the University's School of Geography, Earth and Environmental Science, said: "This exciting opportunity will provide us with a unique set of Arctic sea ice and seawater samples collected from northern Canada right up to the North Pole. The way that Antony will be collecting sea ice and seawater samples is simply not possible through conventional ship-based sampling, and the samples could provide clues about how the Arctic is changing now and has changed in the past."

The team must reach the North Pole by April 28, so that they can fly home from a tented camp with an airstrip run during the winter.

Antony also has to meet an increasingly busy schedule. Before returning to Plymouth he will be leading another expedition across Greenland, followed by an appearance at the International Polar Year Conference in Oslo in June.

Antony will be the only British participant at the Polar Teachers Conference, where he will talk about his school outreach work and the launch of his non-profit company Education Through Expeditions.