Water shortages may loom in the future of 1.3 billion people living downstream from the Himalayas in Nepal, due to climate change, says new research from Ball State University.
“Melting Himalayan Glaciers Threaten Domestic Water Resources in the Mount Everest Region, Nepal” a four-year analysis by faculty and students from Ball State and Kathmandu University in Nepal, found that retreating glaciers and snowpack loss threaten the area that relies upon seasonal melt for domestic water resources.
A multiuniversity research team, led by Kirsten Nicholson and Klaus Neumann, geological science professors in Ball State’s College of Sciences and Humanities, has spent the last several years studying the impact of climate change on communities high in the Himalayas.
Geological science professors Kirsten Nicholson and Klaus Neumann
“This is a serious problem,” Nicholson said. “As the glaciers continue to shrink, not only will the local communities face water shortages during the Winter dry season and the Spring/Summer during the pre-monsoon season, but continued melting will impact the major rivers which supply over 1 billion people downstream.”
During regular visits to Nepal from 2016-2020, the team found that an average of 60 to 65% of the water used for domestic purposes is from glacial meltwater in mountainous communities in the Khumbu Valleyod of Nepal.
In some communities, this number reaches almost 90%, and the main river is around 77% glacial meltwater during the pre-monsoon season. Ten major rivers originate in the Himalaya and supply freshwater to 1.3 billion people living in its watershed, Neumann said.
“This indicates that communities there are especially vulnerable to the retreat and eventual disappearance of glaciers and permanent snow fields in response to continued warming trends,” the researchers said. “By developing a baseline of the hydrologic cycle for the Khumbu Valley, this study benefits future monitoring of these critical water resources and provides a snapshot of pre-monsoon domestic water resources in the Khumbu Valley against which the effects of climate change can be observed.”
Predicting climate-driven changes before they occur, and quantifying how the contribution of meltwater to domestic water resources will change, will allow the high-altitude Nepali communities to be better prepared. In addition, the approach implemented in this project may be applied to other high-altitude environments where snow and glaciers contribute to valuable water resources.
The study, which was published in the scientific journal “Frontiers in Earth Science,” is the first to examine what happens when climate change impacts a large area. Previous related studies from the Himalayas have primarily focused on river discharge, rather than specifically sampling water sources used for domestic purposes such as drinking, cooking, bathing, cleaning, laundry, and other daily necessities.
“The sensitivity and vulnerability of high-altitude regions to the effects of a shifting climate make them ideal long-term sites for monitoring climate change,” Nicholson said. “The Hindu Kush-Himalayan Region and Tibetan Plateau are often referred to as the Earth’s ‘Third Poleas.’ They contain the greatest number of glaciers outside of polar regions. They are also referred to as the ‘Water Tower of Asia,’ because they are the headwaters for some of the continent’s largest rivers, including the Indus, Ganges, Brahmaputra, Yangtze, and Yellow rivers.”
Ball State researchers also are working with Nepal’s communities of Phortse and Lobuche and the NGO Action for Nepal to help residents better understand their water resources and earthquake risks. These communities plan to build water filtration and storage systems so that they can reduce their vulnerability. This work is funded through Geoscientists without Borders.
The team also continues to monitor both the water quality and the water quantity to gain a better understanding of the long-term implications of climate change. This information is vital for water resource management, particularly downstream in larger communities and cities, Nicolson said.