A Bristol physiotherapist has set off on the world's first carbon neutral trek across the ice caps of Greenland.

Richard Spink, 31, and colleague Raoul Surcouf, 40, have started the challenge to make their way across the 290-mile expanse using only human, solar and sail power.

They set sail from Mountbatten Marina in Plymouth on Sunday with Bristolian Ben Stoddart, 43, skippering the 40ft island packet boat they are using.

Most people who set off on such treks fly to the start point but the team, who will be carrying out research for the Bristol Glaciology Centre, felt they should not leave a carbon footprint while looking at damage caused by fossil fuels.

They expect the 2,200-mile crossing of the North Atlantic to take between 17 and 21 days.

Mr Spink, of Cotham, and Mr Surcouf, of West London, will then have to unload their kit and carry everything to the edge of the ice.

Mr Stoddart, of Montpelier, will leave the pair to complete their trek across the ice cap and will sail on to Disco Bay, before returning to pick them up 35 days later.

The trip has taken three years to plan and will raise funds for the Teenage Cancer Trust.

Mr Spink said: "It will be tough for the first week on the boat when we are being thrown about."