The journey to the Chhota Shigri Glacier, in the Himalayan peaks of northern India, begins thousands of feet below, in New Delhi—a city of twenty-five million people, where smoke from diesel trucks and cow-dung fires dims the sky and where the temperature on a hot summer day can reach a hundred and fifteen degrees˳ The route passes through a churning sprawl of low-land cities, home to some fifty million people, until the Himalayas come into view: a steep wall rising above the plains, the product of a tectonic collision that began millions of years ago and is still under way˳ From there, the road snakes upward, past cows and trucks and three-wheeled taxis and every other kind of moving evidence of India’s economic transformation˳ If you turn around, you can see a great layer of smog, lying over northern India like a dirty shroud˳ In the mountains, the number of cars drops sharply—limited by government regulation, for fear of what the smog is doing to the ice˳ The road mostly lacks shoulders; on turns, you look into ravines a thousand feet deep˳ After the town of Manali, the air cools, and the road cuts through forests of spruce and cedar and fir˳
A few months ago, I followed that route with an international group of scientists who were travelling to Chhota Shigri to assess how rapidly it is melting˳ Six of us were pressed together in a van packed with scientific instruments, cold-weather gear, and enough provisions to last several days˳ My guides were two Indian scientists, Farooq Azam and Shyam Ranjan˳ Azam, a thirty-three-year-old former bodybuilding champion, has made more than twenty trips to Chhota Shigri˳ This time, he would be carrying out measurements for the National Institute of Hydrology, in Roorkee˳ Ranjan, a large, soft-spoken man who grew up in a village on the plains of North India, had never been on a Himalayan glacier˳ He was hoping to extract an ice core—a sample from deep inside the glacier, which would provide a detailed picture of the area’s past climate˳ It would be the first such sample to be taken from the Indian Himalayas˳
There are a hundred and ninety-eight thousand glaciers in the world, and, while many of them have been studied extensively, the nine thousand in India remain mostly unexamined˳ On the Chinese side of the Himalayas, researchers have performed thorough surveys, but, according to one American scientist, “the other side of the Himalayas is a black hole˳” The reasons are largely financial: India is a relatively poor country, and there are scant funds available for research˳ “To adequately study the Himalayan glaciers, we need thirty to forty times more money than we actually receive,” A˳ L˳ Ramanathan, a glaciologist at Jawaharlal Nehru University, who oversaw our expedition, told me˳
Scientists from other countries have moved in to fill the void˳ Markus Engelhardt, a German, joined us in Manali, and a second vehicle carried a group of Norwegian glaciologists who were heading to a lake near Chhota Shigri to take samples of sediment dating back as far as twelve thousand years˳ For the Norwegians, the expedition amounted to a tutorial: they were hoping to teach the Indian scientists how to do similar experiments˳ “There’s a thirty-year lag in India,” Jostein Bakke, one of the Norwegians, said˳ “Without a firm understanding of the long-term dynamics of the climate, making predictions about it is like playing the lottery˳”
In India, the lack of precise knowledge has caused confusion˳ Two years ago, an article in Current Science, an Indian publication, concluded that “most of the Himalayan glaciers are retreating˳” Soon afterward, the Indian Space Research Organization found nearly the opposite, that eighty-seven per cent of them were stable˳ Some scientists expressed doubts about both studies, saying that data gathered only by satellites are not reliable for making such judgments˳ “You really can’t tell anything unless you see the glacier up close,” Azam said˳ “That’s why I come up here˳”
For the people who live on the Indian subcontinent, the future of the high-mountain climate is of more than academic interest˳ The three great rivers that flow from the Indian Himalayas—the Ganges, the Indus, and the Brahmaputra—provide water for more than seven hundred million people in India, Pakistan, and Bangladesh, and they power numerous hydroelectric plants˳ Already, villages in India and Pakistan are experiencing more frequent flooding from the melting ice; scientists are predicting even more˳
At thirteen thousand feet, our van arrived at a pass known as Rohtang La—“pile of corpses,” so called because of the many people who have frozen to death trying to get through˳ Winter was coming, and in a few days the pass would close for six months˳ The Norwegians had wanted to come earlier, but they received permission from the Indian government only at the last minute; for researchers hoping to work on India’s glaciers, the bureaucracy can be as big an obstacle as the lack of funding˳ “We do not want to get trapped on the other side for the winter,” Bakke said˳
When we reached the top of Rohtang La, the horizon appeared: a line of mountains skidding downward half a mile to the valley floor˳ Zigzagging through switchbacks, we made our way down˳ A new landscape emerged; instead of forests and grassy hillsides, there were boulders, barren slopes, and expanses of scree˳ The only signs of human habitation were fallow, neatly marked farm plots that crept up the valley walls at improbable angles˳
Near the valley floor, we veered onto a rocky trail that tracked an icy river called the Chandra˳ Our van halted and a group of men appeared: Nepali porters, who led us to an outcropping on the river’s edge˳ Chhota Shigri—six miles long and shaped like a branching piece of ginger—is considered one of the Himalayas’ most accessible glaciers, but our way across was a rickety gondola, an open cage reminiscent of a shopping cart, which runs on a cable over the Chandra˳ With one of the porters working a pulley, we climbed in and rode across, one by one, while fifty feet below the river rushed through gigantic boulders˳
Once we had arrived at the other side, we made our way across a rock-strewn field to get to our base camp, elevation twelve thousand six hundred and thirty-one feet˳ The sun was setting and whatever warmth was left vanished˳ In a few minutes, it was dark, and the stars came out, forming a dome of light so bright you could almost read a book˳
Annual expeditions to Chhota Shigri began only fourteen years ago, so relatively little is known about its climatic history˳ Chhota Shigri and the other glaciers of the eastern Himalayas are unusual, in that, unlike the majority of the world’s glaciers, which get most of their snow from winter storms, they get much of theirs from the summer monsoons, which tend to insulate them from more rapid melting˳ (Most of the glaciers of the Karakoram Mountains, in Pakistan, are not receding at all; it’s one of the few places in the world where this is the case˳)
The data are also limited by the uneven quality of the expeditions˳ Glaciologists can spend hundreds of thousands of dollars on research trips, but Azam and Ranjan had only a few thousand dollars to buy equipment and to pay porters˳ Some glacial expeditions extract ice cores using cranes and ferry them home by helicopter˳ The Indian scientists would transport their cores in dry ice, using a portable cooler, of the kind you might use to chill beer for a picnic, driving them by car back to Ranjan’s laboratory, in New Delhi—a sixteen-hour trip˳ Some of the experiments that they planned to perform on Chhota Shigri seemed comically rudimentary˳ In one, to measure the volume of meltwater flowing out of the glacier, a graduate assistant would toss a wooden block into the water and time its float downstream˳
In the morning, the sun rose over the mountains, but for hours the high-walled valley remained shaded and bitterly cold˳ Unlike glaciers in other parts of the world—Greenland, say, or the Alps—many of those in the Himalayas lie at the bottom of narrow valleys that get only a few hours of direct sunlight each day˳ As a result, they are melting more slowly than they would on flatter ground˳ It was not until 8:20 A˳M˳ that the sun shone on our camp; by midafternoon the valley was in shadow again˳
Markus Engelhardt’s first task was to check the camp’s weather monitor, which had been planted four months earlier, and recorded temperature, solar radiation, and barometric pressure˳ There was an array of similar instruments installed throughout the camp; one of them, a five-foot-tall aluminum thistle with a crown of flaps, looked like something you might find in a Santa Fe sculpture garden˳ Engelhardt had two other weather stations on the glacier, and he was eager to download their data, which would allow him to construct a precise record of fluctuations in the local climate˳ As he watched information scroll across the screen of his laptop, Engelhardt, who had been stoic during our long ascent, could barely contain his enthusiasm˳ “I want to go back to the office right now and start studying the data,” he said˳
The team set out into the valley, following a stream that was flowing from the glacier˳ There were nine of us, including three graduate assistants who’d come with Azam and Ranjan˳ I had imagined a smooth carpet of ice that led to the top of the glacier˳ Instead, there was a rough track of boulders, a destructive path that marked Chhota Shigri’s retreat˳ Thousands of years ago, as the glacier moved forward, debris from the valley walls was torn loose by the advancing ice and tumbled onto its face, creating a craggy obstacle course˳
Azam had not visited since 2013, when he was completing a doctorate at the University of Grenoble, in France˳ (His thesis topic: the effect of the climate on Chhota Shigri and the surrounding glaciers˳) Like many of the glaciologists I encountered, Azam entered the field not because he was drawn to science but because he loved the outdoors˳ Born in the plains state of Uttar Pradesh, he grew up seeing the Himalayas on television and dreamt of going there˳ In college, he took a sensible path, studying chemistry, but he was also athletically inclined; he won several bodybuilding titles, including Mr˳ Jawaharlal Nehru University˳ After he finished a master’s degree in chemistry, his teachers urged him to go into medical research˳ But, he said, “I was being pulled by some invisible force˳”
That same year, he had signed up for a mountaineering course offered by the Indian Army, which took place on the Dokriani Glacier, near the Chinese border˳ During the course, Azam noticed a series of bamboo rods protruding from the snow: ablation stakes, basic instruments of glaciology˳ “Until then, I didn’t realize you could work on a glacier,” he told me˳ Not long afterward, he went to Grenoble, where he spent the next three years studying ice, making field trips to India every summer˳ “When I am in the mountains, on the glacier, I feel close to myself—I’m far from everybody, there’s no technology, and I can think,” Azam said˳ “Only recently has the science become more important to me˳”
Ranjan, who is thirty-one, spent years examining glaciers as a graduate student in Switzerland, but he had never been to one in India, where the terrain is much more rugged˳ On the trail, in his heavy clothes—layers of thermal underwear and fleece and a down jacket—he cut a husky figure˳ As we started off, he worried that he was not fit enough to complete the expedition˳ “I am not sure that I can do this,” he said˳ He moved slowly, panting heavily˳ The porters practically skipped across the rocky ground as they carried several hundred pounds of our equipment, as well as dozens of eggs˳
