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Fifty-four years after Sir Edmund Hillary and Tenzing Norgay scaled Mt Everest, their sons say the mountain is now so ravaged by climate change that they would no longer recognise it.
On the eve of this weekend's Live Earth concerts, Peter Hillary and Jamling Tenzing Norgay yesterday issued a timely warning that global warming is rapidly changing the face of the world's highest mountain and threatening the survival of billions of people who rely on its glaciers for drinking water.
The base camp where Sir Edmund and Norgay began their ascent is 40m lower than it was in 1953.
The glacier on which it stands, and those around it, are melting at such a rate that scientists believe the mountain, whose Nepalese name, Qomolangma, means Mother of the World, could be barren rock by 2050.
Up to 40,000 Sherpas who live at the base of the Himalayas face devastation if vast new lakes formed by the melted ice burst and send a torrent of millions of tonnes of water down the slopes.
Mr Hillary, who has himself twice reached Everest's summit, said: "Climate change is happening. This is a fact. Base camp used to sit at 5320m. This year it was at 5280m because the ice is melting from the top and side. Base camp is sinking each year.
"For Sherpas living on Mt Everest this is something they can see every day but they can't do anything about it on their own."
The warning came as a survey revealed that most Britons remain unconvinced about the extent of climate change and that terrorism, crime, graffiti and even dog mess are more pressing issues for the UK.
The Ipsos-Mori poll found that 56 per cent of people believe scientists are still debating whether human activity is contributing to climate change. In reality, almost all agree that it is.
Just over half of people, 51 per cent, believe climate change will have little or no effect and more than one-third admitted they were taking no action to reduce their carbon emissions.
Speaking before the seven Live Earth concerts, which organisers hope will be a catalyst for action on global warming, Jamling Tenzing Norgay, who has also climbed Everest, said the mountain was serving as an early warning of the extent to which it is already changing the planet.
Scientists believe all glaciers in the Himalayas, which are between 0.8km and nearly 5km in length, will be reduced to small patches of ice within 50 years if trends continue.
Mr Norgay said: "The glaciers have receded a great deal since my father's time. There are many things he wouldn't recognise today ... I think the whole face of the mountains is changing."
The glacial retreat presents a double peril for those who live in the Himalayas and the populations of India and China, where the water flowing from the mountains accounts for 40 per cent of the world's fresh water.
The rapid rise in the rate of glaciers melting - from 42m a year in the 40 years to 2001 to 74m a year in 2006 - has created huge lakes in just a few years.
A United Nations study of the 9000 glacial lakes in the Himalayas found more than 200 at risk of "outburst floods", unleashing thousands of cubic metres of water per second into an area where 40,000 people live.
In 1985, Lake Dig Tsho in the Everest region released 10 million cubic metres of water in three hours. It caused a 10m-high wall of water which swept away a power station, bridges, farmland, houses, livestock and people up to 88km downstream.
Scientists estimate the most dangerous lakes today are up to 20 times bigger. One of those, Imja Tsho, did not exist 50 years ago and lies directly above the homes of 10,000 people.
Nepalese scientists say the worst-case scenario is a cascade effect whereby one overflowing lake empties into another, starting a chain reaction which would kill thousands and wipe out agriculture for generations.
Peter Hillary said: "I've seen the result of glacial lakes bursting their banks and it's just catastrophic. It's like an atomic bomb has gone off."
- Independent
