title: Four billion people facing severe water scarcity.
abstract: Freshwater scarcity is increasingly perceived as a global systemic risk. Previous global water scarcity assessments, measuring water scarcity annually, have underestimated experienced water scarcity by failing to capture the seasonal fluctuations in water consumption and availability. We assess blue water scarcity globally at a high spatial resolution on a monthly basis. We find that two-thirds of the global population (4.0 billion people) live under conditions of severe water scarcity at least 1 month of the year. Nearly half of those people live in India and China. Half a billion people in the world face severe water scarcity all year round. Putting caps to water consumption by river basin, increasing water-use efficiencies, and better sharing of the limited freshwater resources will be key in reducing the threat posed by water scarcity on biodiversity and human welfare.
authors.affiliation: Twente Water Centre, University of Twente, Drienerlolaan 5, 7522 NB Enschede, Netherlands.
authors.forename: Mesfin M
authors.identifier: 0000-0002-3573-9759
authors.initials: MM
authors.lastname: Mekonnen
authors.affiliation: Twente Water Centre, University of Twente, Drienerlolaan 5, 7522 NB Enschede, Netherlands.
authors.forename: Arjen Y
authors.identifier: 0000-0002-4769-5239
authors.initials: AY
authors.lastname: Hoekstra
mesh_terms: D044822:Biodiversity; D002681:China; D003247:Conservation of Natural Resources; D004326:Drinking; D060766:Drinking Water; D005618:Fresh Water; D006801:Humans; D007194:India; D045483:Rivers; D012621:Seasons; D014881:Water Supply
chemical_list: D060766:Drinking Water
keywords: envrionmnetal flow requirement; high spatial resolution; monthly water scarcity; water footprint