Greenpeace has decided to photograph hundreds of volunteers lying naked on Switzerland's Aletsch glacier. Environmentalists regard glaciers as key indicators of global warming and the signs are not good: glaciers are shrinking rapidly. This report from Imogen Foulkes:

TUNICK: If I feel your tan line is too much for this installation, I might ask you not to pose.

It all sounds a bit like a gimmick for the media, but Marcus Allerman, campaign director of Greenpeace, believes the image of naked people on Europe's largest glacier is relevant:

ALLERMAN: People posing on the glacier, it's like they show their vulnerability, free of any protection, it's actually what happens with our nature, it's free of any protection and it's kind of sick, the glacier is like bleeding out or sweating. It shrunk last year 150 metres.

And in fact people from all over the world came to Switzerland to take part in the event. One of them was Bill Worthington:

WORTHINGTON: It's a small thing to do to make a difference in the world, not to be a Bill Gates and leave a few billion dollars behind but to have some small impact of my existence here to hopefully get people to change the way we're treating the planet.

The Aletsch glacier isn't just one of the world's beauty spots. Water from its ice melt fills Europe's rivers, irrigates crops and cools nuclear power stations. But in fifty years, scientists say the ice could all be gone. No wonder perhaps that Greenpeace and 600 volunteers were ready to go to such lengths.

Imogen Foulkes, BBC News, in the Swiss Alps

in urban settings
with images of cities/towns in the background

a gimmick
something which is not serious that is used to attract people's attention or interest

glacier
a large mass of ice

relevant
connected with what is happening

vulnerability
being easily harmed or hurt

shrunk
became smaller, reduced in size

impact of my existence
the influence that my life has on the planet (by me taking part in events like this)

beauty spots
places, usually in the countryside, which are particularly attractive

No wonder
it's not surprising

ready to go to such lengths
here, prepared to do something this unusual

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