Urban Deserts

An estimated 400 million people currently live in cities with perennial water shortage. The number is slated to go up to 1 billion by 2050 due to rising urban population and the impact of climate change.

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THE CRISIS at Cape Town has shown what unplanned urbanisation can do to water availability in the world’s urban centres. Not only are our metropolises headed to a dry future, the scarcity will increase as people are migrating to urban areas at unprecedented rates. About 54 per cent of the world,or 3.9 billion people, live in urban areas and they will grow between 60 and 92 per cent by the end of the century, says a study published in Nature this January. As a result, the urban water demand will increase by 80 per cent by 2050, it adds. Most worryingly, “climate change will alter the timing and distribution of water,” it says.

About 400 million urban dwellers currently face water shortage, states a 2014 study published in Global Environmental Change (see ‘36 per cent cities to face water crisis by 2050’ on p54). This when the average global temperature has not even risen by 1.5°C above pre-industrialisation levels. What will happen when it rises by 2°C? A study, published in Earth System Dynamics in November 2017, has made projections for those scenarios. A 1.5°C rise in the average global temperature will expose 357 million urban dwellers to extreme droughts while the figure for a 2°C rise will be 696 million, it says (see ‘A dry future’ on p55). The number of city dwellers facing water shortage by 2050 could be much higher, about 1 billion, says the Nature study.

These rises in temperature are no longer hypothetical scenarios. A draft report by the Intergovernmental Panel on Climate Change (ipcc) leaked this February warns that the average global temperature is set to rise by 1.5°C by the 2040s. What will happen to our cities?