Spy-Satellite Images Reveal How Climate Change Is Rapidly Melting the Himalayan Glaciers

Over the last several years, on Mt. Everest, veteran alpine guides have reported seeing an increasing number of human skeletons and frozen corpses. One guide named Gelje Sherpa told the Times that when he first summited, in 2008, he found three bodies, and during a recent season he found six. “They often haunt me,” he said. The bones and preserved bodies of climbers who didn’t make it to the summit, revealed as the peak’s glaciers recede, are, for some, more than enough evidence that warming temperatures are melting the Himalayan glaciers at an increasingly quick clip. A new study, published on Wednesday in the journal Science Advances, added a significant layer of proof, finding that, over the past forty years, the average rate that the Himalayas have lost ice has doubled. While the paper’s findings have dire consequences for the millions of people who live just below Himalayan glaciers, they are also vitally important in aiding officials and engineers tasked with planning for the region’s entire population of 1.6 billion people, all of whom rely on the rivers that these glaciers feed.

If things continue as they are now, the Himalayan glaciers
 are likely to lose two-thirds of their total ice. For a region
 already plagued by poverty and inequality, that
eventuality is catastrophic.

The study’s lead author, Joshua Maurer, a doctoral student in earth sciences at Columbia University, used recently declassified spy-satellite images from the nineteen-seventies to observe how the volume of the region’s largest glaciers has changed. Scientists had already documented the rate at which the Himalayas had lost ice mass in the course of the twenty-first century using more sophisticated satellite imagery. Maurer developed computer software that created three-dimensional images from the overlapping pictures, allowing him and his colleagues to digitally “walk” across the glaciers’ surfaces as they appeared in 1975. In the end, they found that the six hundred and fifty largest glaciers across India, China, Nepal, and Bhutan, which together represent fifty-five per cent of the region’s total ice volume, have lost the equivalent of a vertical foot and a half of ice each year this century. That’s roughly twice as much as what they lost from 1975 to 2000, when temperatures were, on average, 1.8 degrees Fahrenheit cooler. (Previous studies that looked at melt since the seventies, like Maurer’s, found similar results, but with much less precision and over a smaller area.) “The correlation we observed between rising air temperatures and acceleration of glacial melt really highlights how vulnerable these glaciers are to climate change,” Maurer told me by phone on Monday. “As temperatures continue to rise, ice loss is going to continue to accelerate.”

Read the story from The New Yorker by Carolyn Kormann - “Spy-Satellite Images Reveal How Climate Change Is Rapidly Melting the Himalayan Glaciers.”