This month, Regional Environmental Change published a study that analyzes the “socio-hydrology” of the artificial ice reservoirs, commonly called “artificial glaciers,” of Ladakh, a high mountain region located in the area known as the Trans-Himalaya. The study assesses the effectiveness of these structures as a strategy of adaptation to seasonal water shortages and to the effects of climate change on the glaciers of the Himalaya, which the Ladakhi rely on for water to irrigate agriculture.
Why Artificial Glaciers?
Ladakh has always experienced seasonal water scarcity, according to Marcus Nüsser, a co-author of the study. Nüsser told GlacierHub, “Water scarcity issues are frequent and an annual phenomenon in Ladakh because of the complete dependence of irrigated agriculture from meltwater, especially from the glaciers.” Since the glaciers reside at a much higher altitude than the villages, “the meltwater from these water sources comes quite late in the year. And so there’s a regular problem of severe water scarcity every year in those months when sowing of the cultivated plants starts,” that is, in early spring.
Climate change has increased water shortages in mountain regions worldwide, according to another study published last month. Artificial glaciers help to alleviate seasonal water shortages by storing meltwater from winter months in ice structures at an altitude lower than the natural glaciers and higher than the cultivated fields. There are several different types of artificial glaciers, which are described later in this article. Due to their lower altitude, these stores of ice melt earlier than the natural glaciers, “providing irrigation just in time for the start of the agricultural season,” as Nüsser writes in his chapter of the 2016 book Ethnic and Cultural Dimensions of Knowledge, titled, “Local Knowledge and Global Concerns: Artificial Glaciers as a Focus of Environmental Knowledge and Development Interventions.”
How They Work
Constructed ice reservoirs, along with water management systems, have long been in Ladakh’s technological repertoire. According to Nüsser’s chapter of Ethnic and Cultural Dimensions of Knowledge, Ladakh “has a long history of water harvesting and community management of water resources.” This history includes tanks for storing meltwater, called zings, as well as an official called a Chudpon who “ensures equitable distribution of water.” The chapter notes the practice of “birthing glaciers” by placing pieces of glaciers in caves at high altitudes found in the Gilgit-Baltistan region of northern Pakistan. The Regional Environmental Change study further mentions the tradition of “snow harvesting,” which involves building small barrier walls.
Since then, four types of modern ice reservoirs have been developed, as identified by Nüsser and his coauthors:
Basin structures store ice similarly to how traditional zings store water. While zings are generally built around the same level as fields, basins for ice storage are located at altitudes higher than cultivated fields so that water can freeze. The advantage of ice basins over zings, and the advantage of ice reservoirs over water reservoirs, is that evaporation is minimized and so more water is retained.
A second type of ice reservoir involves building a sequence of loose rock walls into a river. This slows down water velocity enough that the water freezes in layers. This type of structure, called a “cascade,” was first created in 1987 and was the first structure to be called an “artificial glacier.”
A third type of artificial glacier diverts stream water to freeze in small, shaded side valleys. This strategy also relies on reducing the velocity of river water.
The most recently developed type of artificial glacier, the Ice Stupa, was highlighted in a New Yorker photo essay last month. An Ice Stupa uses piping to divert stream water. The water is shot upwards through a sprinkler and freezes in vertical layers in a conical structure that resembles Buddhist stupas. Due to their vertical shape, ice stupas have less surface area exposed to sunlight, and so they can reside at altitudes as low as the villages themselves while remaining frozen through the winter. A challenge of the Ice Stupa, Nüsser told GlacierHub, is that since they rely on pipes, “they need a relatively sophisticated intake system that is not blocked during the cold seasons.” Developed by Sonam Wangchuk, the Ice Stupa won the Rolex Award for Enterprise in 2016.
Reception of Ice Reservoirs
Ice reservoirs are not always successful, according to Nüsser and the recent study. Success depends on “the situation during the wintertime, whether or not ice accumulation is successful,” Nüsser told GlacierHub. The study cites “high inter-annual climatic variability, frequency, and duration of freeze-thaw cycles together with variances in design” for this irregularity.
Further, Nüsser explained, artificial ice reservoirs are only implementable in a very specific environment–that is, a “cold, arid environment… where you have extremely low temperatures during the wintertime because of the high altitude, the position, and where you have on the other hand a very arid situation.” A local climate must include “frequent freeze-thaw cycles to have the successful formation of large quantities of ice. That’s why you cannot use such systems in every area where you have irrigated cultivation.” Still, there are enough places that meet this description that ice reservoir technology has the potential to spread to other locations. Nüsser told GlacierHub, “I’m sure there are possibilities to transfer this technology, for example, to other trans-Himalyan regions,” and possibly to “parts of Bolivia, maybe, parts of Peru, or northern Chile.”
However, as Nüsser and his coauthors point out, support for ice reservoirs is not unanimous. Storing meltwater in the form of ice to service upstream communities in Ladakh deprives downstream communities of this water. According to the study, “There have been protests against the [Ice Stupa] project as it abstracts water from the main stream, thereby reducing water availability for downstream communities and households.”
Presented as an appropriate method of adaptation to global warming, artificial glaciers have received considerable attention. The home page of the website for the Ice Stupa Project reads, “Join Ladakh as it gears up to fight climate change and melting glaciers.” The Regional Environmental Change study observes that although the Ice Stupa Project was the costliest ice reservoir initiative to date, the project was able to receive its funds through crowdsourcing by “promoting these structures in the context of global climate change.”
The authors of the study, though, do not see artificial glaciers as an appropriate method of adaptation to climate change. Nüsser reasonably suggests that the term “artificial glacier” be jettisoned in favor of “artificial ice reservoir.”
“It’s not really a glacier,” Nüsser told GlacierHub. “It’s just a seasonal storage of water in the form of ice to increase meltwater availability in the early season.” Unlike natural glaciers, ice reservoirs only remain frozen for part of the year, and so ice does not accumulate from year to year. “They can not replace the natural glaciers,” he said.
His study, of course, echoes this conclusion: “It is important to see them as site-specific water conservation strategies rather than climate change adaptation, which is neither their original function, nor something they are likely to accomplish.”
Although they do not match the expectations that the term “artificial glacier” may raise, artificial ice reservoirs do, overall, succeed in supplying much needed water to farmers at a critical point in the growing season, according to Nüsser and the study. Storing ice in these structures “helps the farmers to increase the number of irrigation cycles for the cultivated fields.” The aid in water supply allows farmers to “cultivate cash crops like potatoes, in the case of Ladakh, and they can make some more income from these agricultural productions.”
Ice reservoirs alleviate water shortages in upstream communities in the short term, the study concludes, but these ice structures will not slow the effects of climate change on natural glaciers. If glaciers disappear, then there will be no meltwater to be stored in the artificial ice reservoirs. Nüsser told GlacierHub, “In the context of global warming, we have to imagine a time when there is no meltwater available.” For now, though, these artificial ice reservoirs help the farmers of Ladakh and provide an example of creative adaptation to immediate strains caused by global warming.
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