In 1992 the Dagu Glacier, hidden inside the valleys of China's Sichuan Province, was discovered by Japanese scientists with the help of a satellite. After investigating for a week, these scientists realized that the Dagu Glacier was, at the time, both the youngest and lowest glacier in the world, sitting at an altitude of only 3,000 to 5,000 meters above sea level, when generally, most of the world’s glaciers sit between 5,000 and 8,000.
Now, the young glacier is in danger due to global warming, and its short stature only means it may more quickly melt. That’s why, as Bloomberg reports, a group of Chinese scientists is intervening, shielding the glacier with thermal white sheets to reflect the sun, and while they are not under the impression it will stop the melt, their hope is that the blanket, known as a “geotextile” will slow the melting down.
“All the human intervention methods that we’re working on, even if they prove effective, are only going to slow down” the melting, Zhu Bin, the 32-year-old Nanjing University associate professor leading the expedition told the publication. “If the Earth keeps getting warmer, in the end, there is no way to protect the glaciers forever.”
While it was discovered in the early ‘90s, Dagu existed for decades before human eyes touched it. As found in a 2020 study published in the journal Regional Environmental Change, between 1957 to 2017, glaciers in the Yulong Snow Mountain region, where Dagu lies among others in the Qinghai-Tibetan Plateau, have retreated by over 64%.
One in particular, the Baishui River Glacier, has retreated by over 12 meters annually, or about the length of a weeping willow vanishing every year.
According to reporting by the South China Morning Post, Dagu’s present area is only one-third of what existed in the 1970s.
“For material scientists like us, our ultimate goal is to put a material to good use,” Zhu said in a video by the South China Morning Post, “When we realized this particular method could serve its purpose in possibly delaying the melting glaciers we were very excited.”
This isn’t the first time Zhu and the scientists have embarked on such a project. Before Dagu, they conducted the experiment on another glacier in Xinjiang in 2020, laying the material across 200 square meters of the glacier, and according to Zhu, it successfully slowed down the ice melting by three to four times.
“This trial could take three to five years,” Zhu said via the Post.
Geoengineering with geotextiles around the world
Other scientists have undertaken similar initiatives. While the Chinese scientists are covering an area near Dagu’s base with 4,300 square feet (400 square meters) of the sheets, even bigger covering projects have been conducted on Switzerland’s 12,000 feet tall Rhône Glacier, as well as in Italy and Germany.
The idea of reflecting the sun back to protect glaciers isn’t even limited to our modern plight of global warming. In fact, as Scientific American reports, early as 1947, residents around Switzerland’s Aletsch glacier were spreading sawdust across the roof of an ice cave created for tourists to shield it from the sun’s radiation. As the climate crisis began to tiptoe into the public’s attention, in 1990, some ski resorts began spreading the giant white blankets across slopes, using layers of plastic to protect their most lucrative assets from the sun and water.
However, as the Swiss Alps have lost 60% of their volume since 1850, with 2022 setting a record for the glaciers losing 6%, the geotextiles currently being deployed, could, as one glaciologist, puts it, reduce ice melt “by about 50 to 60, 70%.”
Matthias Huss of the University of Fribourg in Switzerland is head of the glacier monitoring network Glamos and the lead author of a recent study on geotextile use. For the last seven years, he and his team have covered nine different sites of Swiss glaciers with the artificial mitigation method, doubling the area they’ve covered since 2012.
While Huss estimates that over the last seven years, the coverings have allowed the Rhône Glacier in southern Switzerland to preserve around 35 meters in ice thickness, similar to the conclusions of the Chinese scientists, the study concludes that in the long term, scaling glacier coverings will not stop the melting.
“Whilst local interventions can be efficient and profitable, a hypothetical application to the larger scale shows that saving Alpine glaciers by technological solutions is neither achievable nor affordable,” the study’s conclusion somberly reads.
If blankets were used on Switzerland’s 1,000 glaciers, it would cost the country $1.52 billion per year. Geotextiles, Huss said via Scientific American, were “never intended as a way to save the glaciers.”
Still, scientists are using it, along with other measures like snowmaking, as a means to buy time. Snow, whether synthetic or natural, has a high albedo (reflectivity) that can bounce a lot of the sun’s radiation skyward, like the blankets, staving off melting.
That’s why scientists at the University of Lucerne in Switzerland and GlaciersAlive, a nonprofit organization that focuses on water conservation, are working on snowmaking technology that is powered by elevation rather than electricity, to lower artificial snow’s carbon footprint and wield it to save the disappearing Morteratsch Glacier.
A pilot is being funded by Innosuisse, a Swiss government agency that promotes innovation, to the tune of $2.15 million. The team, as Scientific American reports, is looking for a smaller glacier for its next test—and is seeking investment.
According to Huss, snowmaking “always slows down the losses. And the process that is suggested absolutely works.” Still, under the Paris climate scenario, by 2060 the glacier will lose 35 % of its volume even with the proposed snowmaking. Still, without the artificial snow, it could lose 56% to 71%, meaning that blasting snow guns at the glacier could potentially reduce more than half of the melting over the next four decades.
Can blanketing glaciers help the Tibetan Plateau?
Back in the Tibetan Plateau, throughout June, Zhu and his team navigated high altitude dizziness, waist-high snow, and waiting out rainstorms as they secured the sheets. The sheets are made of cellulose acetate, a natural fiber made from plants, in order to minimize its environmental impact.
While the types of sheets the team is using will not be suitable for large glaciers, as glaciers are always moving, the team plans to decide after the end of the three to five-year trial, if they should expand the effort across China, or even move abroad. They also have the idea to use the substance as small particles deposited by drones on less accessible glaciers.
It took tens of millions of years for the Tibetan Plateau to rise to its height today, and aside from the critical habitats and fragile ecosystems maintained by the glaciers, for centuries people have relied on them for their livelihoods.
Since its discovery, Dagu has supported the lives of tens of thousands of people who live around it, from fueling a bustling tourism industry that employs 2,000 people, attracting a deluge of 200,000 tourists annually to the drinking water the meltwater provides that also helps to generate hydropower.
In fact, just last week, the world’s largest hybrid solar-hydro plant produced electricity for the first time on Tibetan Plateau. It’s part of a huge renewable production base planned by the Chinese government to generate clean energy for 100 million households. It’s one cog in China’s bigger plan to be carbon neutral by 2060, reach a peak in its carbon emissions by the end of the decade, and have renewable capacity exceed that of fossil fuels by 2025. Back in June, it achieve that last goal three years ahead of schedule. However, with projects like hydro relying on meltwater, climate mitigation, and adaption projects like this are also at the whim of climate change itself.
That’s why Zhu and his team want to work on improving the technology, to buy even more time. “We are trying to improve the material,” he said via the South China Morning Post, “not only in terms of how much it can reduce temperatures but also how well it can repel water and how durable it is when used to cool a glacier.”
“So scientifically, I don’t think there’s much controversy. It’s just a matter of improving the technology behind the materials.” In voicing that he thinks we need to have a wider perspective beyond stopping the melting, he says the sheets also help raise public awareness about the speed of the glacial melt through real-world applications of science and technology.
According to Huss, while it may not work as a large-scale solution for the potential it has to disrupt ecosystems on huge glacial habitats, the coverings make sense for locally relied upon glaciers.
“It's a very good solution to locally combat the effect of climate change,” he said, especially when there are specific economic benefits. However, according to Hus, the real answer is “very clear.” “It’s to save the climate.”