Ranulph Fiennes pulls out of Antarctic challenge
Sir Ranulph Fiennes has pulled out of an expedition across Antarctica during winter because of severe frostbite.
The 68-year-old was injured after a fall while skiing during training at a base camp in Antarctica. He used his bare hands to fix a ski binding in temperatures around -30C.
His evacuation to South Africa is being hampered by blizzard conditions.
Sir Ranulph is said to be "gutted," but his five team-mates will still embark on the 2,000-mile (3,219km) trek.
Tony Medniuk from the "Coldest Journey" expedition said Sir Ranulph had been due to lead the team from the front on skis, and had been practising his skiing in whiteout conditions when he fell.
"In seeking to reattach his binding he felt that he couldn't get it on and had to take his glove off in very cold conditions and exposed his hand to snow and as a consequence he has contracted frostbite," he told the BBC.
- Frostbite is damage to the skin and tissue due to exposure to freezing temperatures
- It can affect any part of the body, but extremities like fingers, ears, the nose and toes, are particularly vulnerable
- When it is cold the body diverts blood flow from the extremities to vital organs like the heart and lungs
- As the blood is redirected, the extremities get colder and fluid in these tissues begin to freeze
- Initially you may feel pins and needles and painful throbbing, but as the tissues freeze the area becomes numb
- Ice crystals form, damaging cells, and the low blood flow starves the tissue of oxygen
- If the blood flow is not restored soon enough the tissue will die and may need to be amputated
- Almost all cases of frostbite can be prevented by wearing appropriate clothing and avoiding unnecessary exposure to cold
"After five years of preparation, a small slip like this and a few moments can undermine the most meticulous preparation," he added.
The team is attempting to evacuate Sir Ranulph by transporting him by skidoo to the Princess Elisabeth Station, about 70km away from his current position. From there he will be flown to Novo to get a connecting flight to Cape Town.
Blizzard conditions are currently making any evacuation impossible and Sir Ranulph will be unable to move until conditions ease.
The trek is known as The Coldest Journey on Earth. No human being has managed to walk across Antarctica in winter.
The team will face some of the toughest conditions on Earth - near permanent darkness and temperatures dropping close to -90C.
The expedition - from the Russian base of Novolazareskaya to the Ross Sea - is due to begin on 21 March and is expected to take six months.
The journey is to benefit Seeing is Believing, a charity which tackles avoidable blindness.
Sir Ranulph's past feats include becoming the first person to reach both poles by surface means and the oldest Briton to reach the summit of Mount Everest, aged 65.
Guinness World Records describes him as the world's greatest living explorer.
This is not the first time the explorer has experienced frostbite. In 2000, he lost the fingers on his left hand during an unaided attempt to reach the North Pole.
When he returned to the UK, he was told he would have to wait several months before they could be amputated to allow the partially damaged tissue to heal. But he decided to do the job himself and carried out the amputations using a fretsaw.