The air was thin as a group of scientists trudged through the snow near the summit of the Dagu Glacier in southwest China on a gloomy June morning. Up there, 3 miles above the sea, it was silent except for the sound of flowing water—a constant reminder of the ice melting right beneath their feet.
As they ascended, oxygen canisters tucked into fleece jackets, porters carrying thick rolls of white cloth walked beside them. The researchers planned to spread these sheets over more than 4,300 square feet (400 square meters) of the mountain. The film was designed to reflect the sun’s rays back into the atmosphere, effectively shielding the glacier from heat and hopefully preserving some of its ice.
For decades, Dagu has supported the lives of tens of thousands of people who live in its vicinity. Glacier melt water provides drinking water and helps generate hydropower, while the majestic views of the Tibetan Plateau can attract more than 200,000 tourists a year, fueling an industry that employs more than 2,000 people. Now everything is at risk as the planet warms.
Chinese scientists had no illusions that their project would save Dagu. Over the past half century, the glacier has already lost more than 70% of its ice. One researcher described such efforts to a local newspaper as similar to a doctor’s efforts to merely extend the life of a terminally ill patient by a few years. The only real remedy would be to drastically reduce emissions of planet-warming carbon dioxide, the world’s largest source of which is China.
“All the human intervention methods we are working on, even if they prove to be effective, will only slow down” the melting, said Zhu Bin, a 32-year-old associate professor at Nanjing University who led the expedition. “If the Earth continues to warm, eventually there is no way to protect the glaciers forever.”
This was not the kind of fieldwork Zhu chose to do.
A materials scientist by training, he spent most of his time in laboratories in Nanjing and New York, including more than a year of battery storage research at Columbia University. The move to the glacier puzzled some of his academic colleagues, who teased him about leaving the comfort of his research in an air-conditioned room. His family worried about his safety, but he says it worked out in the end because they saw protecting the glaciers as “something that is difficult but right”.
Covering glaciers with sheets of reflective material is not a new idea. European ski resorts have been using white blankets to protect the snow for nearly two decades. However, China has only just begun to experiment with this approach. Small-scale trials on the Xinjiang and Dag glaciers since 2020 appear to have slowed their retreat.
