Water shortages are one of the main environmental disasters predicted to increase in frequency and severity as the climate continues to warm over the coming decades. But it seems that for the majority of people across the globe, the issue of having enough fresh water year round is already a serious problem. A new report has found that there are four billion people – two-thirds of the planet’s population – who face severe water scarcity for at least one month a year.
In the first study to look at water availability from month to month, the researchers were able to assess some regions down to a resolution of just 60 square kilometers (23 square miles). Of the four billion found to be living under conditions of severe water shortage for at least part of the year, over half of the people were found to live in India and China, while a shocking half a billion were found to face severe water shortages for the entire year. The report found that there is enough water to support the global population, but that people and agriculture are often concentrated in smaller areas, using more water than the region can sustain.
Map showing how many months different regions have to face water scarcity. Mekkonen et al. 2016
“Groundwater levels are falling, lakes are drying up, less water is flowing in rivers, and water supplies for industry and farmers are threatened,” explains Professor Arjen Hoekstra, who coauthored the study published in Science Advances. “In this research, we established the maximum sustainable ‘water footprint’ for every location on earth, and then looked at actual water consumption. If the latter is much greater than what is sustainable, then there can be said to be severe water scarcity.”
If a region's consumption of fresh water, be it from underground aquifers or rivers and lakes, was found to be twice the amount that was put back into the system through natural processes such as rain, then it made its way onto the red list. But it’s not just the obvious deserts of North Africa, Australia and the Middle East that are at risk. Other regions such as southern Europe and the eastern U.S., as has been seen recently with the drought in California, are also running at a deficit.
Most of this water being used is going towards agriculture, with the production of meat being particularly water intensive as it is thought to use 25 percent of all water used globally: It takes over 15,000 liters of the stuff to produce just one kilogram of beef. Despite the food production industry using around 70-80 percent of the water consumed globally, around half of all food – amounting to about 2 billion tonnes (2.2 billion tons) – is thrown away before it reaches our plates.
Water scarcity has been rated by the World Economic Forum as the one of the three greatest global risks, alongside climate change and mass migration. This discovery that the situation is even worse than had been previously accepted, and that if the current unsustainable use continues it will get much worse, simply adds to the urgency to address the problem. The researchers say that there should be caps on water use put in place for river basins, alongside increased transparency in how much water is used to make food and other products, to help drive an increased understanding of the true cost to this planet.