Over half world's population in severe water scarcity, study
Sunday, February 14, 2016, 7:14 PM - Scientists say two-thirds of the global population, about 4 billion people, live with severe water scarcity for at least one month during the year. Meanwhile, half a billion on Earth experience this all year round.
The study published on Friday in Sciences Advances, assessed the availability of "blue water", meaning both fresh and groundwater, using a high resolution global model. It analyzed data from 1996 to 2005.
Some of the main driving forces behind the rising global demand for water include, the rising world population, improving living standards, changing consumption patterns and expansion of irrigated agriculture, the study notes.
The study also shows areas of severe water shortage exist where there is twice as much water demand as there is availability. Individual homes tend to require the least water with about one to four per cent of the total, according to the researchers.
India and China make up nearly half of those living with fragile water resources. Other regions highlighted included central and western United States and Australia.
In the World Economic Forum's most recent report, water crises was listed as one of three greatest global risks in the next decade, alongside climate change and mass migration.
This is the first time global water scarcity has been measured on a monthly basis as previous studies have been evaluated annually, according to the study.
Previous research measured on an annual basis had given totals of about 1.7 to 3.1 billion, compared to the current 4 billion people affected. These new findings, "implies that the situation is worse than suggested by previous studies," the authors note.
"Measuring at a basin scale and on an annual basis hides the water scarcity that manifests itself in particular places and specific parts of the year," the study highlights. "One or a few months of severe water scarcity will not be visible when measuring water scarcity annually, because of averaging out with the other, less scarce months."
Scientists believe placing caps on water use for river basins, increasing water-use efficiency and better sharing of freshwater resources are key in reducing the threat of water scarcity on biodiversity and human welfare. It will be crucial for governments and companies to generate water footprint benchmarks based on available technology.
"Meeting humanity’s increasing demand for freshwater and protecting ecosystems at the same time, thus maintaining blue water footprints within maximum sustainable levels per catchment, will be one of the most difficult and important challenges of this century.”