A new global water scarcity map could help in tackling the shortage and its spillover effects
A new global map of water scarcity points out countries where the water usage is greater than water availability at least for one month a year—and, on that, India looks parched. While, predictably, the western states of Gujarat and Rajasthan and patches in the southern states of Tamil Nadu, Andhra Pradesh and Telangana experience more than 100% water scarcity (water usage twice that of water availability) round the year, the rest of the country faces such scarcity for anywhere between a third to three-quarters of the year.
Globally, more than 4 billion people—more than half the world’s population—live in areas facing absolute duress (100% water scarcity) for at least one month a year, as per the map developed by researchers at the University of Twente, the Netherlands. The map, Nature reports, was drawn basing on estimations of monthly withdrawal of water using data on crop types, population density and water evaporation. The research assumed that 80% of the local water would need to stay in the river and water systems to support the local ecosystem and deemed the location “water scarce” for a particular month if people dipped into this reserve. The map points out that parts of Africa and Mexico, southern Europe, Turkey and China could experience local hardship because of scarcity. The scarcity, however, may not always remain a local problem because it could trigger difficulties beyond the places and times of local water scarcity—many of Europe’s food and other goods import depend on reliable water supply in China, for instance. The data from the research could perhaps guide policy-makers in working around the scarcity and draft strategies to tackle spillover effects.