Glacier Blankets, Titlis Glacier, Switzerland, 2024

From far away the blankets covering the glaciers of Mount Titlis look like plastic sheeting. You have to get very close to realize these immense coverings – the size of 14 football fields – are reflective geotextiles made of double-layered synthetic fleece that seem to have more in common with the soft woolly material you would use to make a felt tree ornament than with plastic.

Switzerland is making a go of extending the life of its 1,500 glaciers by covering them in these protective materials during summer months to slow the melting of their glaciers . Scientists – and tourism and ski hill operators – spend weeks covering the large bodies of ice ahead of summer and weeks peeling them off again ahead of winter in an attempt to inoculate the ice against global warming. In the past seven years the Swiss have doubled their coverage of the Alps.

The specialized fabric is semi-permeable and has a high albedo, meaning it reflects more short-wave radiation than melting ice and snow. This reduces the amount of energy available for the glacier to melt. The benefits are threefold: the ice is insulated, its cooler temperatures stabilized; rain is collected, which cools the glacier when it evaporates; it inhibits the formation of puddles that can warm up and seep water into the snow.

Some studies show the blankets are working. Yet, they remain controversial because almost everyone – the public, scientists themselves – wonder if it’s worth the effort. By how many years can they realistically extend the life of the glaciers? Especially in light of the extraordinary cost – covering all of the glaciers would cost Switzerland an estimated $1.5 billion yearly. Very few countries have Switzerland’s resources, making it painfully clear that the blankets are unscalable and inequitable. And is the effort in vain if no concrete action to tackle warming and greenhouse gas emissions globally, beyond the borders that contain these particular glaciers?

The Titlis glaciers have been getting tucked in for the summer since 2021. Yet, many of the very old ones, their texture reminiscent of elephant knees, continue to shrink away, sliding into glacier rivers that run into glacier lakes.