Episode 1: The towers of Ladakh

A mechanical engineer teams up with an unlikely band of students who use middle school math and science to create artificial glaciers that irrigate Ladakh, a region in India hit hard by climate change.

The Giant Shara Ice Stupa, standing 33.5 meters tall, is the highest recorded so far.

Ciril Jazbec

A mechanical engineer teams up with an unlikely band of students who use middle school math and science to create artificial glaciers that irrigate Ladakh, a region in India hit hard by climate change.


ARATI KUMAR-RAO: I went right up to the stupa. And that's when it hit me. It felt almost spiritual.

PETER GWIN (HOST): In 2019, Arati Kumar-Rao was in the North of India, on one of the highest plateaus in the world, standing before a massive cone of ice.

KUMAR-RAO: And I was just thinking, my God, you know, this is a temple—in a very different way—but it is a temple, because water is everything. Water is life for these people.

GWIN: The cone of ice was called an ice stupa: an artificial glacier made by villagers, and named after a type of sacred Buddhist structure.

KUMAR-RAO: You feel it. You feel the gravity of the situation—of what's happening and why this needed to be built. And then the love with which the people have built this. It's not something that they've done out of duty, or out of, you know, it was not a ritual or anything. This they did out of love, because they wanted to help their village. They wanted to survive.

GWIN: Arati says, this monstrous cone of ice was a surprising solution to a problem that seems insurmountable.

I’m Peter Gwin and this is Overheard at National Geographic: a show where we eavesdrop on the wild conversations we have here at Nat Geo—and follow them to the edges of our big, weird, beautiful world.

This week: How villagers in the mountains of northern India are dealing with water shortages caused by shrinking glaciers. More after this.

ARATI KUMAR-RAO: You can live many days without food, or without shelter, or whatever, but water is vital.

GWIN: Arati Kumar-Rao is an environmental photographer and writer working on a story about ice stupas for National Geographic. She says if anyone understands how vital water is, it’s the people of Ladakh.

KUMAR-RAO: This land of Ladakh is a desert. It's a cold desert, but it has glaciers, and it has snowfall—and that’s what keeps it alive.

GWIN: Ladakh is in the region of Kashmir, at the top of India—way up high in the mountains. It’s flanked to the west by Pakistan, and to the east by China. And ever since the partition of India in 1947, Pakistan, India, and China have all fought over the disputed region.

KUMAR-RAO: But, truly, we are facing an enemy that does not have a face or a uniform. And that enemy is, of course, climate change.

GWIN: When the glaciers in Ladakh melt, the water trickles down into the valley, where the people use it to farm. But because of climate change, the glaciers are shrinking, which means meltwater comes later in the year—or it doesn’t come at all.

KUMAR-RAO: If a whole valley of many villages on the valley floor have depended upon that meltwater, and the glaciers are gone and there's no snow, and you don't have any water for eight months of the year—how are you going to live?

GWIN: In Ladakh, it’s getting harder to do so. The mountain range that Ladakh sits on neighbors the Himalayas, but the Himalayas are taller, and they block most of the rain clouds.

SONAM WANGCHUK: So we are said to be in the rain shadow of the Himalayas.

GWIN: Sonam Wangchuk is a mechanical engineer who’s lived in Ladakh his whole life. He says Ladakh only gets about four inches of rain and snow a year. That’s why for centuries they’ve relied on canals that run from the glaciers to water their crops. And against all odds, they grow barley, wheat, carrots, spinach, and fruits like apricots, apples, and pears.

WANGCHUK: In spring, which is when farmers really need the water most—because unless you start early in spring in these cold deserts, your crops will not mature by the time winter sets in—so springtime, which is April/May, is a crucial time when you must have water.

GWIN: But because the glaciers are shrinking, there’s not much melt in spring. And then in August, because of climate change, there’s a lot of melt, plus occasional bursts of rain from monsoon clouds, which lead to flash floods.

WANGCHUK: So when you really don't need water, you have a flood. When you do need water, there is a trickle, or a drought.

GWIN: This is the kind of problem that engineers like Sonam spend years trying to solve. But Sonam’s not working with other engineers. In fact, he spends most of his days, with kids—kids who have “failed” at school. It turns out, Sonam’s not just a mechanical engineer who knows a thing or two about water in Ladakh—he’s an education reformist, who in 1988 created a school for Ladakhi kids who were failing in traditional school.

WANGCHUK: And mind you, in those days, 95 percent of the students used to fail at the high school-leaving exams, after spending like 10 years in those schools. So I decided engineering was my –

GWIN: Wait–95 percent of the students failed the exam?

WANGCHUK: Yeah. Believe it or not.

GWIN: Wow.

WANGCHUK: 95 percent failed. And yet I thought—and thought and thought—that actually it was a bigger surprise that five percent passed with the system that I saw.

GWIN: Sonam says the students were taught in Urdu or English, even though they didn’t speak those languages at home.

WANGCHUK: So I learned that there were so many problems the children were facing, mainly stemming out of this, you know, situation where we in the mountains had no relevance to the textbooks that came from outside teachers, who came from outside, and so on. So I saw that as a bigger challenge that Ladakh was facing, and decided that more than applying mechanical engineering, Ladakh and its children needed to be liberated from a very, very difficult education system which failed them—for no fault of theirs.

GWIN: So at Sonam’s school, students run the campus. They grow their own food, milk the cows, and they work together to solve problems—serious problems, like the water shortage that’s threatening the Ladakhi way of life.

WANGCHUK: And later at our school, when we were looking at all these solutions, we said, How should we apply science or maths to make ice in villages, or at the top of the village, and keep it till spring time, so that it doesn't prematurely melt before spring, and melts right when the farmers need and when there is not enough water in the streams.

GWIN: So he and the students started experimenting. They were trying to figure out how they could store ice until spring. Sonam remembered hearing a story when he was young about people creating their own glaciers. But it sounded more like a legend.

WANGCHUK: It’s kind of a fairy-tale story, like where I would be told that you bring a mother glacier from one valley and a father glacier from another valley, and put the two together under a big rock in your valley, and a baby glacier is expected.

GWIN: That sounds perfect, man. And it also, like you said, sounds like a fairy tale.

WANGCHUK: Yeah, it sounds like a fairy tale. But then I would wonder, there must be something in it, otherwise people wouldn't do it.

GWIN: Sonam and his students knew ice couldn’t be stored flat—say, across a field—because it would melt before people needed the water.

WANGCHUK: But then we saw one fine morning outside our school, under a bridge, there was a chunk of ice which had lasted into mid-May—which proved that it is technically possible to have ice till when people need it.

GWIN: Sonam says, it wasn’t any cooler under the bridge.

WANGCHUK: And what is different under the bridge is not actually the temperature, because outside the bridge also the temperatures are spring temperatures. So what is different, we saw, was that there was no sunlight—direct sun—on the ice.

GWIN: Sonam and his students thought, If we could shield ice from sunlight, then maybe we can store it till spring.

WANGCHUK: But that is easier said than done.

GWIN: A little ice under a bridge made sense, but creating shade for a massive chunk of ice that would keep an entire valley fertile? That’d be a lot harder.

WANGCHUK: Any material would be unaffordable at that scale, so what came to our help was geometry.

GWIN: Geometry. You know, the math you learned in 9th grade that crushed your soul and made you become a journalist? Well, you might remember that some shapes can have big volumes but low surface areas.

WANGCHUK: So if the ice is frozen in the shape of a hemisphere or a cone, then it might last much longer without any bridge or any shade because of its geometry—low surface area for the sun to melt, and high volume for the farmers to use.

GWIN: OK, so that’s brilliant, right? But how do you build a really large cone of ice?

WANGCHUK: It's not easy to make pyramids, solid pyramids. Ask the Egyptians. So we knew that it had to be simple, and you couldn't have people carrying blocks of ice high up—10 stories, 12 stories. So we thought, we'll make the water do it–do the work—rather than us moving ice up.

GWIN: This time, Sonam and his students found answers in science class. They’d already learned in middle school about water hydraulics. And one basic idea is that you can use gravity to direct water where you want it to go.

WANGCHUK: Upslope, if you put a pipe and bring it downstream, then there's pressure in the pipe. Now to that pressure, if you put a fountain at the outlet at the other end of the pipe, then it sprays the water into the air.

GWIN: Just like a sprinkler. And then they could then hang that sprinkler from a frame shaped like a tree.

WANGCHUK: So once this water is sprayed into the minus 20 [degrees] air, it sucks the heat out of the little droplets that is sprayed. And as it falls down, it freezes. And slowly, it naturally takes the shape of a cone.

GWIN: Boom! And that’s how you make an artificial glacier that melts in spring. In 2015 Sonam raised 125,000 dollars on a crowdfunding site, and with that money, he and a couple of students built a stupa. It was as tall as a six-story building, and when it began to melt in April, it watered a field of poplar trees. And it lasted until June. But despite that success, it was hard to get people in Ladakh excited about what was still ... just a chunk of ice.

WANGCHUK: We thought, you know, ice cones are not interesting. People around may not relate to some ice cone. And we thought how to make the innovation close to the people’s hearts. And we saw that these ice cones very much resembled with another conical structure that's built with mud and stone, called stupas.

GWIN: A stupa is a type of Buddhist structure that represents enlightenment.

WANGCHUK: So entire region of Ladakh, Tibet, and many parts of India are dotted with these spiritual monuments called stupas. So we said, why not call, why not present, our solution as an ice stupa?

GWIN: And it worked.

WANGCHUK: Suddenly we saw village people coming and circumambulating around the ice stupas while praying mantras from Buddhist scriptures, and some even prostrating before the ice stupas like a real spiritual monument that stupas are.

GWIN: Now that the locals were on board, Sonam set out to build more ice stupas.

WANGCHUK: So this time we built a seven-story-tall ice cone, which contained roughly one million liters of water, and it lasted till August.

GWIN: Oh my gosh. Wow, the whole summer. Wow.

WANGCHUK: Yes, on a sunny day, it would give us roughly 50,000 liters of water.

GWIN: That’s like five tankers of water every day. Pretty soon, Sonam and his students were teaching villagers how to build ice stupas. Again, writer Arati Kumar-Rao.

KUMAR-RAO: The enthusiasm of the people when they want to build a stupa, or are building a stupa, it's just infectious. It's really—it's fun. Everybody wants—it's like they're solving their problem.

GWIN: And to think Sonam came up with the solution with a bunch of students that people thought were failing.

WANGCHUCK: So these students were rejected by the system, have gone on to become world-famous documentary filmmakers, politicians who became, you know, the education minister of the region.

GWIN: Oh, wow, really? Came from the school?

WANGCHUK: Yes, from this school. I mean, the one who took up education ministry had failed five times in the system.

GWIN: Wow.

WANGCHUK: So similarly, some of them have taken studying further about the ice stupas and promoting it in their villages.

GWIN: So far they’ve built 26 ice stupas this year, and more are planned for the winter. But for all the success of ice stupas, Sonam says they’re just a Band-aid, and a cry for help.

WANGCHUK: We don't think of them as something to be satisfied with, or take pride in even, because these cannot solve our problems of a scale like climate change. So it has to be a global action that can only save us.

GWIN: So now that’s what Sonam’s focused on—inspiring global change.

WANGCHUK: Last year, on Mahatma Gandhi's birth anniversary, we said, Why not try and change the world and their behavior? So we were a bit audacious, but why not try? And hence, we started a movement called the I Live Simply movement, in which we tried to make the idea and concept of ice stupas not just a water solution for mountain people in Ladakh, but as an SOS message from people who are at the forefront of climate change challenges.

GWIN: The motivation behind this SOS is simple.

WANGCHUK: As Gandhi said, we say: please live simply, so we may simply live.

GWIN: Well said. More after this.

GWIN: Nat Geo photographers have taken a lot of photos of Ladakh over the years. And it looks like Mars. You can find those photos in your show notes. We also have a link to the article Arati Kumar-Rao wrote about Sonam’s ice stupas. Also, it’s not just Ladakh that’s facing a water crisis: The rest of India has a complicated relationship with water too. We’ve got a story that looks at how India's trying to improve its water infrastructure system. You can find those stories and more in our show notes—they’re right there in your podcast app.


Read Arati’s story about Sonam Wangchuk and his artificial glaciers in this month’s issue of the magazine.

It’s not just Ladakh that’s facing a water crisis. Learn more about India’s struggles with water infrastructure, with more reporting by Arati Kumar-Rao.

You can read about the complicated history of Kashmir, an area that’s witnessed two wars and a longstanding insurgency.

Check out more content from Nat Geo Magazine's July 2020 issue, Everest: Journey to the Roof of the World, at natgeo.com/mounteverest.

Also explore:

Check out photos of Sonam’s solar-powered school built from mud.

You can also make your own pledge to live simply by visiting the I Live Simply movement’s website.

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