The study estimates that 1.693–2.373 billion people globally will face water scarcity by 2050. Among them, 19.2%–31.2% will live in India, making it the most severely affected country. As many as 23 large cities downstream from the Third Pole are projected to face severe water scarcity, accounting for 7.9% of the global average. “This highlights the role of the Third Pole in terms of global urban water security and sustainable development,” said Dr. LIU Zhifeng , corresponding author of the study at Beijing Normal University.

Although as many as 276 (95%) of the large cities projected to face water scarcity will be able to alleviate such shortage through infrastructure options such as seawater desalination, groundwater exploitation, reservoir construction and interbasin water transfer, environmental trade-offs associated with these solutions can be significant, warns the study. For the other 5% of cities, no feasible solutions have been found, due to their geographic and socioeconomic disadvantages. The majority of these cities are located in the Third Pole surroundings and downstream region. “We believe there is an urgent need to control urban population growth and urbanization rates in these cities,” said Prof. HE Chunyang, first author of the study atBeijing Normal University .

 

The projections were made using a framework that assesses population growth, water demand and solutions for water scarcity under potential socioeconomic and climate scenarios.

 

Editor’s note: This study is supported by STEP, a TPE-related science project.