Ice Towers

Near a village in Ladakh, a cold desert region in northwestern India, a tall pipe juts up out of the ground. On winter nights, water sprays from the top of the pipe into the frigid air. With temperatures dipping to -29°C (-20°F), the liquid quickly freezes as it falls to the ground. Over time, a giant cone of ice forms around the pipe. It will eventually tower up to 10 stories high. The colossal structure serves an important purpose: It supplies people living nearby with a reliable source of water.

A tall pipe juts up from the ground near a village in Ladakh. This cold desert region lies in Northwestern India. On winter nights, water sprays from the top of the pipe into the cold air. Temperatures dip to -29°C (-20°F), so the liquid quickly freezes as it falls to the ground. Over time, a giant cone of ice forms around the pipe. It will eventually reach up to 10 stories high. The huge structure serves an important purpose. It supplies local people with a dependable source of water.

Ladakh sits on a windswept plain between two mountain ranges, the Karakoram and the Himalayas, in Northwestern India (see Himalayan Home). Blocked by the mountains, little rain reaches the high, flat plateau. Ladakh averages just 10 centimeters (4 inches) of rain every year. People living in the area instead get water from huge masses of ice called glaciers, which cover the sides of the mountains. During warmer months, parts of the glaciers melt. The water flows down mountain streams to villages on the plateau, where people use it for farming. But warming temperatures brought on by climate change are causing the glaciers to shrink, resulting in water shortages in Ladakh.

To help, Sonam Wangchuk, an engineer who grew up in Ladakh, developed a way to build ice towers that serve as artificial glaciers. The structures are called “ice stupas” because they’re shaped like stupas, a type of Buddhist shrine. Ice stupas can hold up to 11 million liters (3 million gallons) of water. They melt slowly to supply water to villagers in Ladakh year-round.

Ladakh sits on a windy plain in Northwestern India. It’s between two mountain ranges, the Karakoram and the Himalayas (see Himalayan Home). Mountains block most rainclouds from reaching the high, flat plateau. Ladakh averages just 10 centimeters (4 inches) of rain each year. People in the area get water from glaciers instead. These huge masses of ice cover the sides of the mountains. In warmer months, parts of the glaciers melt. The water flows down mountain streams to villages on the plateau. People in the villages use it for farming. Now climate change is bringing warmer temperatures. That’s causing the glaciers to shrink, resulting in water shortages in Ladakh.

Sonam Wangchuk wanted to help. He’s an engineer who grew up in Ladakh. So he developed a way to build ice towers that serve as artificial glaciers. The structures are called “ice stupas.” They’re shaped like stupas, a type of Buddhist shrine. Ice stupas can hold up to 11 million liters (3 million gallons) of water. They melt slowly. That way, they supply water to villagers in Ladakh year-round.

More than half of Earth’s fresh water is frozen in glaciers. These large, slow-moving bodies of ice are found in the world’s coldest regions, like the Himalayan mountaintops and ice-covered Antarctica. Glaciers take hundreds of years to form. They grow each winter as new snow piles up and freezes. In the spring and the summer, some of the glacier ice melts and flows into streams down mountainsides or into the ocean.

All over the world, glaciers are slowly disappearing—including in the Himalayas. “Increased temperatures lead to less snowfall,” says Joseph Shea. He’s an earth scientist who studies glaciers at the University of Northern British Columbia in Canada. With less snow to replenish them each winter, the glaciers are shrinking so they store less water.

Water from the glaciers also arrives in Ladakh at a different time of the year than in the past. This is happening because parts of the glaciers found lower down on the mountains have melted away. Since ice remains only at higher elevations, its meltwater must travel farther to reach towns on the plateau. It doesn’t arrive at farms until the summer, when it’s too late to use for watering crops.

More than half of Earth’s fresh water is frozen in glaciers. These large bodies of ice move slowly. They’re found in the world’s coldest regions, like the Himalayan mountaintops and ice-covered Antarctica. Glaciers take hundreds of years to form. They grow each winter as new snow piles up and freezes. In the spring and the summer, some of the glacier ice melts. It flows into streams down mountainsides or into the ocean.

Glaciers are slowly disappearing all over the world. It’s happening in the Himalayas too. “Increased temperatures lead to less snowfall,” says Joseph Shea. He’s an earth scientist who studies glaciers at the University of Northern British Columbia in Canada. Less snow supplies the glaciers each winter, so they shrink. That means they store less water.

Water from the glaciers still arrives in Ladakh. But it comes at a different time of the year than in the past. That’s because the lower parts of the glaciers have melted away. Ice remains only higher on the mountains. So its meltwater must travel farther to reach towns on the plateau. It doesn’t arrive at farms until the summer. Then it’s too late to water crops. 

People had previously tried solving the water shortage in Ladakh by creating artificial glaciers. But they were built high up in the mountains, making them hard for villagers to reach. Wangchuk thought the ice should be closer to settlements to make it easier for farmers to access the water in the spring. So the came up with the Ice Stupa Project. In 2013, he and his team built their first ice stupa.

To create a stupa, workers lay a long pipe to collect glacier water flowing through cracks underground, where temperatures are warmer (see How an Ice Stupa Works). The pipe connects to a vertical spout near a village. Because the pipe starts at a higher elevation and ends at a lower one, only the force of gravity is needed to draw water through the pipe—no pumps or electricity required. Around the spout, workers build a dome-shaped wooden frame covered in netting. During winter nights, when the air temperature is below freezing, a person opens the pipe’s valve. Pressure causes water to shoot out of the top of the spout. The water falls on the netting below and turns to ice.

Periodically, workers increase the height of the ice stupa’s spout so the tower can grow taller. This process builds up a large cone of ice, says Simant Verma, a former manager with the Ice Stupa Project. This tall cone shape ensures the ice doesn’t melt too quickly as temperatures warm. The reason is that a vertical mound of ice has less surface area exposed to the sun than a wide, flat glacier containing the same volume of water. Come spring, the ice stupa begins to melt, sending water flowing down to the village. This continues through the early summer.

People had tried to solve the water shortage in Ladakh before. They’d already created artificial glaciers. But these glaciers were built high up in the mountains. That made them hard for villagers to reach. Wangchuk thought the ice should be closer to villages. Then farmers could more easily get the water in the spring. So he came up with the Ice Stupa Project. In 2013, he and his team built their first ice stupa.

To create a stupa, workers lay a long pipe. It collects glacier water flowing through cracks underground. There, temperatures are warmer (see How an Ice Stupa Works). The pipe connects to an upright spout near a village. The pipe starts at a higher point and ends at a lower one, so the force of gravity draws water through the pipe. No pumps or electricity are needed. Around the spout, workers build a dome-shaped wooden frame. They cover it in netting. On winter nights, the air temperature is below freezing. That’s when a person opens the pipe’s valve. Pressure makes water shoot out of the top of the spout. The water falls on the netting below and turns to ice.

From time to time, workers increase the height of the ice stupa’s spout. Then the tower can grow taller. This process builds up a large cone of ice, says Simant Verma. He’s a former manager with the Ice Stupa Project. This tall cone shape keeps the ice from melting too quickly as temperatures warm. The reason is the amount of surface area exposed to the sun. An upright mound of ice has less surface area than a wide, flat glacier with the same volume of water. In spring, the ice stupa begins to melt. It sends water flowing down to the village. This continues through the early summer.

Since 2013, the Ice Stupa Project has built more than 75 stupas in Ladakh. In 2020, with the help of locals, they completed an ice stupa that provides water to the village of Kulum. Between 2007 and 2012, droughts forced many people to leave this town. Now, some residents are returning home. Wangchuk’s team is also training Ladakh’s villagers to make their own ice stupas. The group even holds a yearly contest to see who can build the biggest one.

Since 2013, the Ice Stupa Project has built more than 75 stupas in Ladakh. Locals helped project workers complete an ice stupa in 2020. It provides water to the village of Kulum. Water shortages forced many people to leave this town between 2007 and 2012. Now, some of them are returning home. Wangchuk’s team is also training Ladakh’s villagers to make their own ice stupas. The group even holds a yearly contest. They see who can build the biggest one.

Although ice stupas are helping bring water to Ladakh villagers who need it, the towers won’t be able to solve a much bigger problem. As the threat of climate change grows, natural glaciers will continue to shrink. That means the water available to be stored in ice stupas will also eventually run out. Ice stupas can’t stop climate change, says Wangchuk.

Wangchuk wants the Ice Stupa Project to inspire people to work to protect glaciers—before they’re gone. Verma agrees. “Ice stupas show the world that we are trying to adapt to a problem that is hitting us hard,” he says. “It’s time for you to learn about the problem and take action too.”

Ice stupas help bring water to Ladakh villagers who need it. But the towers can’t solve a much bigger problem. The impact of climate change is growing, and natural glaciers will continue to shrink. That means the water that supplies ice stupas will also run out over time. Ice stupas can’t stop climate change, says Wangchuk.

Wangchuk wants the Ice Stupa Project to inspire people to protect glaciers—before they’re gone. Verma agrees. “Ice stupas show the world that we are trying to adapt to a problem that is hitting us hard,” he says. “It’s time for you to learn about the problem and take action too.”