Such is the rate of global warming that scientists predict that the Lost Mountain glacier in northern Spain will disappear altogether within twenty years.

For the scientists at the Pyrenean Institute of Ecology who are monitoring it, Monte Perdido's glacier is shrinking scarily fast.

"Five years ago we inserted these sticks 10 metres vertically, so we were standing at least 10 metres above the height we are now," said the institute's Ignacio Lopez Moreno as he stood on top of the glacier.

After studying them Spain's environment ministry concluded that 90 percent of the glaciers in the Pyrenees have already disappeared.

"Most probably, this glacier in about 20 years will already be a form of residual ice," Moreno said.

"It will have a greater accumulation of snow at the top, but it will be difficult to say that it is a glacier. This is the future of practically all the glaciers that remain in the Pyrenees."

Glaciers cover ten percent of the world's surface and they're also the biggest reservoirs of fresh water on earth.

But since people rarely live near them, their disappearance is largely going unnoticed.