A frozen desert: The artificial glaciers of Ladakh
Ladakh, ‘the land of high passes’, lies high in the mountains of northern India, resting against the Tibetan border. Although one of the most sparsely populated areas in the states of Jammu and Kashmir, communities have nevertheless made their home in the mountain desert since the dawn of the New Stone Age.
Villages are found at altitudes from 2,700m to 4,000m above sea level, where winter temperatures plummet to more than 30 degrees below freezing. With an annual rain and snowfall of just 100mm, settlements thrive around the glacial streams that feed the Indus and other rivers in the area.
As winter draws to a close, the streams have dwindled to little more than a trickle and farmers must compete for scarce resources to water their newly planted crops. By mid-June, however, the droughts have passed and fast-melting snow and ice once again replenishes the tributaries. After the autumn harvest of crops, farmers no longer rely on the meltwater for irrigation and it flows away into the rivers until the spring drought arrives once again. Sonam Wangchuk, a local mechanical engineer, innovator and educator, has found a novel solution to utilise this excess meltwater and end the seasonal water shortages.
Taking their name from traditional Buddhist sculptures, Ice Stupas are a simple technique of capturing and freezing water in winter that would otherwise pass by, unused. By freezing water into vertical towers, farmers can delay the melting process until springtime, when the water is needed the most.
Building an artificial glacier
The residents of Ladakh are no strangers to the concept of artificial glaciers. In years past, their ancestors would cultivate glaciers in freezing caves, storing them to water their crops throughout the spring. This method, however, relied on very high altitudes paired with north facing valleys to shade the ice from the springtime sun; not to mention the constant attention required to prevent the ice from melting.
By comparison, the Ice Stupa artificial glaciers are much lower maintenance and are surprisingly low-tech. Drawing meltwater from higher in the mountains, Wangchuk harnesses the power of gravity to spray water skywards, removing the need for complicated electric pumps. As the spray freezes in the cold, Ladakhi night air, it falls to the ground, forming conical structures of ice.
As the cones grow vertically upwards, rather than horizontally like natural glaciers, they expose less surface area to the sun, preserving the ice for longer. The melting ice can then be collected and used to irrigate crops during periods of drought, tiding farmers over until the summer sun melts the natural glaciers above.
Testing the water
During the winter of 2013-2014, the villagers of Phyang in Ladakh joined with students at SECMOL and monks from the Phyang monastery to dig a network of canals. Over several months they buried water pipes that would feed the ice mountain, and by January, the team had built an Ice Stupa almost 7m tall.
To test their idea to the fullest, the team picked a spot low on the mountain and in direct sunlight, purposefully choosing the warmest area in the Leh valley. The original Ice Stupa took around a month to grow to 7m tall and was fed by a supply pipe some 15m above the ice cone.
As spring broke, Wangchuk suggested his experiment would be a success if the ice lasted until the start of May. By the time the 1 May 2014 arrived, the Stupa still towered over villagers at 3m tall, continuing to provide water to the valley’s crops. In fact, the Stupa remained standing for a further three weeks as the sun gained in strength, demonstrating that bigger ice cones situated higher up in the mountains could provide water to local villages until well into the summer months.
A second prototype structure was built the following year, and as predicted, watered a forest of trees through the driest months until the start of July. Wangchuk plans to extend the project to create dozens of Ice Stupas and plant over 150,000 trees in the Phyang desert.
In winter of 2016, Sonam Wangchuk and the Ice Stupa project were announced as the winners of the Rolex Awards for Enterprise, receiving a grant to build 20 more glaciers and provide fresh water to sustain crops and livestock year round.
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