World's food production at risk of failure due to growing water scarcity, experts warn

Children pump water at a tap in Kangalita Kangalita, a region in Kenya that has been severely affected by drought.

More than half the world’s food production will be at risk of failure within the next 25 years as a rapidly accelerating water crisis grips the planet, unless urgent action is taken to conserve water resources and end the destruction of the ecosystems on which our fresh water depends, experts have warned in a landmark review.

Half the world’s population already faces water scarcity, and that number is set to rise as the climate crisis worsens, according to a report from the Global Commission on the Economics of Water, published on Thursday.

Demand for fresh water will outstrip supply by 40% by the end of the decade, because the world’s water systems are being put under “unprecedented stress”, the report found.

The commission found governments and experts have vastly underestimated the amount of water needed for people to have decent lives. 

A woman scoops water from a hole she has dug in a dried up riverbed in Lusitu, Zambia, last month. Picture: AP/Themba Hadebe

While 50 to 100 litres a day are required for each person’s health and hygiene, in fact people require about 4,000 litres a day in order to have adequate nutrition and a dignified life. For most regions, that volume cannot be achieved locally, so people are dependent on trade — in food, clothing and consumer goods — to meet their needs.

Some countries benefit more than others from “green water”, which is soil moisture that is necessary for food production, as opposed to “blue water” from rivers and lakes. The report found water moves around the world in “atmospheric rivers” which transport moisture from one region to another.

About half the world’s rainfall over land comes from healthy vegetation in ecosystems that transpires water back into the atmosphere and generates clouds that then move downwind. 

The Global Commission on the Economics of Water was set up by the Netherlands in 2022, drawing on the work of dozens of leading scientists and economists, to form a comprehensive view of the state of global hydrological systems and how they are managed. Its 194-page report is the biggest global study to examine all aspects of the water crisis and suggest remedies for policymakers.

Every 1C increase in global temperatures adds another 7% of moisture to the atmosphere, which has the effect of “powering up” the hydrological cycle far more than would happen under normal variations. 

The destruction of nature is also further fuelling the crisis, because cutting down forests and draining wetlands disrupts the hydrological cycle that depends on transpiration from trees and the storage of water in soils.

Harmful subsidies are also distorting the world’s water systems, and must be addressed as a priority, the experts found. More than $700bn of subsidies each year go to agriculture, and a high proportion of these are misdirected, encouraging farmers to use more water than they need for irrigation or in wasteful practices.

Industry also benefits — about 80% of the wastewater used by industries around the world is not recycled.

Guardian