It’s a troubling fact that more people are moving to cities just as those cities face bigger environmental dangers. Half the world already lives in a city, and by 2050, 75% of us will. In many cases, that growth is exacerbating the risks: for example, increasing carbon emissions while leaving infrastructure less able to cope with shocks such as flooding. Cities already use up to 80% of all the energy on the planet, and produce 75% of emissions, and those percentages are set to grow as the expansion continues.
A new report looks at some of the world’s fastest growing, but environmentally vulnerable, cities, classifying them according to the dangers they face, and laying out ways they might better cope. Put together by the U.K. Department of International Development, Atkins (an engineering consultancy), and the University of London, it covers 129 cities in 20 countries in Asia and Africa.
The categories include "energy intensive, sprawled cities with significant carbon footprints" (e.g. Bangalore and Cape Town), "cities with major climate hazards" (e.g. Kampala in Uganda), cities with severe water and food systems risks (e.g. Karachi), and cities with "multiple risks" (Jakarta) and those relatively low risks (Lilongwe, Malawi—move there). You can see the 129 cities plotted on the map above, according to their color codes.
The report shows how the dangers are likely to be multiplied by poverty, and poor building and infrastructure. Cities in the D.R. Congo, Nigeria, Sudan, and Malawi, for example, have "high proportions of people living in multi-dimensional poverty and informal settlements with poor access to energy, water, and sanitation, and are likely to be impacted greatest by environmental risks such as flooding, cyclones or rises in the price of energy."
Meanwhile, almost half of the 59 Indian cities assessed in the report have "multi-dimensional poverty," and many of those are likely to see large population increases due to demographic changes. Four South Asian cities alone—Kolkata, Mumbai, Karachi, and Dhaka—contain 32 million people in the most at-risk category.
The report, called Future Proofing Cities, recommends cities improve their planning capacity to limit uncontrolled development, build up data and evidence to improve decision-making, and act according to their risk profiles to maximize the benefits of limited resources, among other strategies. Above all, it cautions against a "grow first, tackle environmental risks later" approach, as that is likely to store up ever-tougher problems for the future.
Easier and cheaper to act now. "There is an important—but closing—window of opportunity for cities to take action," it says.