"Glaciers are significant for irrigation because they ___________.

Necessity is indeed the mother of invention. When areas in and around Leh began to experience water shortages, life didn't grind to a halt. Why? Because Chewang Norphel a retired Civil Engineer in the Jammu and Kashmir government came up with the idea of artificial glaciers. 

Ladakh, a cold desert at an altitude of 3,000-3,500 metres above sea level has a low average annual rainfall rate of 50 mm. Glaciers have always been the only source of water. Agriculture here is completely dependent on glacier melt unlike the rest of river/ monsoon-fed India. But over the years with increasing effects of climate change, rainfall and snowfall patterns have been changing, resulting in severe shortage and drought situations. Given the severe winter conditions, the window for farming is usually limited to one harvest season. 

Fondly called the "glacier man" Mr. Norphel has designed over 15 artificial glaciers in and around Leh since 1987. In recognition of his pioneering effort he was conferred the Padma Shri by the President of India in 2015. 

There are few basic steps followed in creating an artificial glacier. A River or a stream of water at a higher altitude is diverted to a shaded area of the hill, facing north, where the winter sun is blocked by a ridge or a mountain range. At the start of winter around November, the diverted water is made to flow onto the sloping hill face through distribution channels. Stone embankments are built at regular intervals which impede the flow of water, making shallow pools that freeze, forming a cascade of ice along the slope. Ice formation continues for 3-4 months resulting in a large accumulation of ice which is referred to as an "artificial glacier ".