Global water consumption has increased almost fourfold in the past 100 years, and many regions can only meet their water demand thanks to essential contributions from mountain regions. In 30 years, almost a quarter of the world’s lowland population will strongly depend on runoff from the mountains. Only sustainable development can ensure the important function of mountain areas as Earth’s “water towers”.
Water is a key resource for the 21st century, and many lowland regions all over the world depend on water resources originating in mountain regions, not least when it comes to irrigating agricultural land. A study led by the University of Zurich has now quantified this dependence for the first time by comparing water supply and consumption in the world’s lowland areas with runoff contributions from the mountains. Based on a high-resolution global model, the study provides detailed information on the dependence on mountain water resources around the globe. The comprehensive analyses were carried out using a regular grid and then compared for every river catchment area of at least 10,000 km2. This allowed for highly differentiated insights into regional characteristics and differences.
Daniel Viviroli, Matti Kummu, Michel Meybeck, Marko Kallio, Yoshihide Wada: Increasing dependence of lowland populations on mountain water resources. Nature Sustainability 2020. DOI: 10.1038/s41893-020-0559-9