Predicting the future of global water stress

January 13, 2014


Researchers from Massachusetts Institute of Technology (MIT) use new modelling tool to calculate the ability of global water resources to meet future water needs. They predict that by 2050 more than half the worlds population will live in water-stressed areas and about a billion or more will not have sufficient water resources.


Credit: UN Photo/Eskinder Debebe

Climate change to affect water availability

Population growth and increasing social pressures on global water resources have required communities around the globe to focus on the future of water availability. Global climate change is expected to further exacerbate the demands on water-stressed regions.

In an effort to assess future water demands and the impacts of climate change, MIT researchers have used a new modelling tool to calculate the ability of global water resources to meet water needs through 2050.

The researchers expect 5 billion (52 percent) of the world’s projected 9.7 billion people to live in water-stressed areas by 2050.

They also expect about 1 billion more people to be living in areas where water demand exceeds surface-water supply. A large portion of these regions already face water stress — most notably India, Northern Africa and the Middle East.

The study applies the MIT Integrated Global System Model Water Resource System (IGSM-WRS), a modelling tool with the ability to assess both changing climate and socio-economics — allowing the researchers to isolate these two influencers.

Mapping future water demands

In studying the socio-economic changes, they find population and economic growth are responsible for most of the increased water stress. Such changes will lead to an additional 1.8 billion people globally living in water-stressed regions.

“Our research highlights the substantial influence of socio-economic growth on global water resources, potentially worsened by climate change,” says Adam Schlosser, the assistant director of science research at the Joint Program on Global Change and lead author of the study. “Developing nations are expected to face the brunt of these rising water demands, with 80 percent of this additional 1.8 billion living in developing countries.”

Looking at the influence of climate change alone, the researchers find a different result. Climate change will have a greater impact on water resources in developed countries. This is because, for instance, changes in precipitation patterns would limit water supplies needed for irrigation.

Developing countries most at risk

When researchers combine the climate and socio-economic scenarios, a more complicated picture of future water resources emerges. For example, in India, researchers expect to see significant increases in precipitation, contributing to improved water supplies. However, India’s projected population growth and economic development will cause water demands to outstrip surface-water supply.

“There is a growing need for modelling and analysis like this, which takes a comprehensive approach by studying the influence of both climatic and socio-economic changes and their effects on both supply and demand projections,” says Schlosser. “Our results underscore this need.”

This article, published by MIT, has been reproduced by PSN. Minor changes, cuts and additions may have been made for the purpose of brevity and relevance.