Even if the countries stick to goals set out in the Paris climate agreement, half the planet’s glaciers will have melted by 2100, according to new research that warns the scale and impacts of glacial loss are greater than previously thought.
At least half of that loss will happen in the next 30 years, which means a rise in sea level, threatening the supply of water of up to 2 billion people, and increasing the risk of natural hazards such as flooding.
For example, in India and China, the Himalayan glaciers are crucial for many important rivers and the vanishing of glaciers will bring a serious livelihood crisis to billions of people.
Researchers found 49 per cent of glaciers would disappear under the most optimistic scenario of 1.5C of warming.
However, if global heating continued under the current scenario of 2.7C of warming, losses would be more significant, with 68 per cent of glaciers disappearing, according to the paper, published in Science.
There would be almost no glaciers left in central Europe, western Canada and the US by the end of the next century if this happened.
The study looked at all glacial land ice except for Greenland and Antarctic ice sheets. If temperature increases are limited to 1.5C of warming, average sea levels would increase by 90mm (3.5in) from 2015 to 2100, but with 2.7C of warming, glacial melt would lead to around 115mm of sea level rise. These scenarios are up to 23 per cent more than previous models had estimated.
Commenting on the study and its findings, David Rounce, a civil and environmental engineer at Carnegie Mellon University and the University of Alaska, Fairbanks and the lead author, said in a statement, “This is the first time we have isolated the number of glaciers that will be lost – before it was the total mass loss.”