Environment

Half the world’s 100 largest cities are experiencing high levels of water stress, with 39 of these sitting in regions of “extremely high water stress”, new analysis and mapping has shown.

Water stress means that water withdrawals for public water supply and industry are close to exceeding available supplies, often caused by poor management of water resources exacerbated by climate breakdown.

Watershed Investigations and the Guardian mapped cities on to stressed catchments revealing that Beijing, New York, Los Angeles, Rio de Janeiro and Delhi are among those facing extreme stress, while London, Bangkok and Jakarta are classed as being highly stressed.

Separate analysis of Nasa satellite data, compiled by scientists at University College London, shows which of the largest 100 cities have been drying or getting wetter over two decades with places such as Chennai, Tehran and Zhengzhou showing strong drying trends and Tokyo, Lagos and Kampala showing strong wetting trends. All 100 cities and their trends can be viewed on a new interactive water security atlas.