Glaciers are more than just breathtaking indicators of climate changeThey will shrink and disappear as a result of global warming. They are also an irreplaceable source to fresh water for many communities.
During the melting season in summer, a portion of mountain glacier surface releases water that is essential to the ecosystem in the valleys below, supplying vast cities – industries – in places like South America and India.
This meltwater is vital for many rural communities, including those who live in remote areas. It can be used to provide water for irrigation and drinking water. These include those who live in the Ladakh ValleyThe beautiful, 470km long valley of, nestled between the Greater Himalayan mountain ranges and Karakoram mountain ranges. It is home to 300,000.
These iconic ranges are home to a large number of glaciers. However, large areas of them also fall within the monsoon. rain shadow zoneThey are extremely dry because the mountains block rainwater. The Ladakh Valley is one of the most arid and coldest mountain regions in the world, with annual rain and snowfall rarely exceeding 100mm – little more than the Sahara Desert – and winter temperatures as low as -30°C.
The people who live in this cold desert face severe water shortages. Their existence depends on the quality of their crops, which are only able to be cultivated for a few months. Often, they are irrigated by glacier meltwater. Climate change has caused glaciers to shrink or disappear at alarming rates in the region over the past decade, reducing the growing season.
An increasingly viable solution to this problem is the construction of ice stupas – artificial glaciers built to store winter water for use in the arid months of late spring and early summer, when meltwater is scarce. Sonam Wangchuk, an engineer from Ladakh, invented the ice stupa in 2013. the ideaIt is important to preserve this tower of Ice as long as possible so that it melts slowly and feeds the fields until the real glacial meltwaters begin flowing later in the summer.
Building local resilience
Our Cryosphere and Climate Change research team has been working in collaboration with Jawaharlal Nehru University New Delhi. studyWe looked at 2,200 glaciers in the greater Ladakh region. We’ve found that 86% have experienced a rise in the height of the snowline of around 300m over the past 42 years. This rate has increased to nearly 10m per year over the past 20 years.
This, combined with dry winters, has resulted in prolonged droughts that are now threatening rural communities’ ability to sustain their lives. It’s not surprising that entire villages are being abandoned or will be soon.
The larger issues can only be solved through the collective action of governments, and society at large. So many hopes are placed on positive outcomes from COP26. However, any solutions to the declining glacier-derived meltwater could ensure a sustainable future for these communities.
Locally, ice stambas can offer a solution or at least partial relief from the effects of shrinking glaciers in short-term. A conical structure made of steel and wood is constructed. Then, water is drawn from nearby streams during the rainy seasons and gravity is used to spray it into the air. This is a simple and inexpensive technique.
The sub-zero temperature quickly freezes the water and forms a conical structure. The end result has the same high, narrow dome-shape typical of Buddhist shrines, hence the “stupa” part of the name, which slows down subsequent melting because the surface area exposed to the sun and warm temperatures is minimised.
The warmer, more dry growing season arrives and the streams at lower altitudes quickly dry up. There is very little water available until June when the meltwater from the glaciers replenishes. It is in this crucial window that the ice stupas start melting, offering an invaluable source of water for irrigation early in the growing season, extending the cropping season by a few weeks – which makes all the difference in this extreme agricultural environment.
Although artificial ice reserves are not new, they were constructed in less efficient ways and higher up in the mountains in the past. This made them more difficult to manage. These ice stupas can now be found near water sources, at the outskirts and near fields. Their size and shape makes them extremely efficient and inexpensive. They can produce millions of litres per year.
We’re now hoping to explore how stupas can best be used to tackle this problem. Our [project]It is still in its infancy, and more work is required to improve certain technical aspects. These include the discovery of additional sites in the Ladakh region as well as other parts of the globe, ways to prevent water freezing in the supply pipesm and how to distribute water to villages and other users. We hope to find some of the solutions by establishing a long-lasting partnership with local ice stupa teams as well as research colleagues.