Study finds world's mountain glaciers melting faster than ever before

The world’s mountain glaciers are melting faster than ever before under the impact of  climate change, shrinking at more than twice the speed of the early 2000s.

That is according to a new comprehensive study published in Nature on Wednesday by a team of international scientists.

"Five hundred gigatons a year of mass loss from glaciers sounds incredible now, but it might sound pretty normal in 10 years from now," said William Colgan, a glaciologist at the Geological Survey of Denmark and Greenland and one of around 60 authors of the report.

They found that seven trillion tonnes of mountain ice has been lost since 2000. Glaciers are melting the fastest in Alaska, while central Europe’s smaller glaciers, like those in the Alps, have shrunk the most proportionally.

"It's been the summer melt, the elevated summer temperatures that have been hammering the Alps with some of these numbers you see coming out of Switzerland with like 3 per cent glacier loss in a single summer by volume,” he said.

Colgan added that there has been no increase in the winter snowfall to compensate for this.

Mountain glaciers, which are basically frozen rivers of ice, act as a freshwater resource for millions of people worldwide.

If they melted entirely, they would release enough water to raise global sea levels by 32cm.

"Mountain glaciers, especially in urbanised areas like western US or the high mountain Asia, where there's a lot of people living, right now those glaciers are actually melting more than they should,” said Colgan.

“This means they're actually contributing more to the local water supply than they normally would. And so people think they're water stressed now, but they are getting extra melt from the glaciers now. But at some point in the perhaps not too distant future, these glaciers will actually start to contribute less."

Scientists say an average of 273 billion tonnes of ice is being lost each year, equivalent to 30 years of water consumption by the world population.

How much ice will be lost by the end of the century will strongly depend on how much we continue to warm the planet by releasing carbon dioxide and other greenhouse gases.