The world's poorest cities can't cope with climate change
But the poorest megacities, where fast-growing populations are often the most vulnerable to these impacts, may already be falling behind.
Among 10 megacities in both the developed and developing world—cities with populations greater than 3 million, a gross domestic product among the top 25 in the world, or both—climate change adaptation spending totaled about $309 billion in 2014–2015, according to a study published Monday in the journal Nature Climate Change.
It was a lot of money, but added up to just 0.38 percent of the global GDP, a fraction of a fraction of both global and local economies.
Further, every city spent the highest percentage of its adaptation budget on bolstering infrastructure, with spending on human welfare services including communications, disaster preparedness, and health services among the lowest.
Within even the lowest allocations, there were some telling trends, however. Megacities in developing nations spent about double the amount of rich megacities on agriculture and forestry, while the wealthiest nations tended to make energy a higher priority.
"The disparities between the spends in the cities were bigger than they expected, and go just beyond the different economic capacities of the cities," said Lucien Georgeson, an economic geographer at University College London and the lead author of the study.
Further, the pattern of spending "suggests to us that the adaptation spend in these cities is not necessarily always to protect people at risk. It might be more to protect infrastructure, and things with an insurable value."
Cities in wealthier nations including New York, Paris, London, and Beijing more than doubled the amount spent on climate adapation, as a percentage of GDP, compared to cities in poorer nations, including Jakarta, Lagos, and Addis Ababa. All three are in regions where urban populations are expected to grow sharply between now and 2050.
The researchers called the difference in spending "staggering."
New York spent the largest sum at $2.3 billion total, or about $268 per resident; London came in second at $1.4 billion. Paris spent most per resident at $550. Beijing's outlay of about $1.2 billion was the highest fraction of its total GDP, at 0.33 percent, or $56 per resident.
By comparison Addis Ababa, Ethiopia, spent about $20 million on climate change adaptation in 2014–2015; 0.14 percent of its GDP, or about $6.50 per resident.
Lagos, Nigeria, ticked up at $7.66 per resident, or 0.15 percent of its total GDP, while the third-lowest city, Jakarta, Indonesia, jumped to $21.3 per resident—although that amounted to just 0.16 percent of total GDP.
Other cities in the study include Mexico City, São Paulo, and Mumbai.
With the greatest population growth over the next 35 years expected in China, India, Nigeria, and Indonesia, the findings suggest that the megacities doing the least to prepare for climate change are the urban areas where the most people will be exposed to those impacts, said Georgeson.
"We were were surprised that the spend per capita was so different," said Georgeson. "Our aim is not to point the finger at cities in developing countries, but to explore whether those cities have enough resources to adapt. It's more like a warning signal about the lower levels of spending in developing megacities, because of their vulnerability and population trends."
This is the first study that has attempted to independently assess how much money megacities are spending to prepare for climate change impacts, and to compare how they're spending it, Georgeson said. While this study included data on 10 cities, "my sense is it would be broadly similar in other cities," he added. "If there's a city that isn't similar, that would be very interesting to find out."
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Georgeson called the finding about high per capita climate spending in Paris an outlier, saying it had more to do with the city's tightly defined formal boundary than an extremely high outlay for climate change adapation.
As for the comparatively large amount of money spent on adapatation in Beijing, as a fraction of GDP, Georgeson and his cohorts credited this to the strength of China's centralized government, which for nearly a decade has been instructing provinces and cities around the country to prioritize climate adaptation.
"Each city is free to do what they think is appropriate for their city, but there's a strong incentive for them to be taking action on climate change," he said. "They're all being assessed on what the central government has set out for them to do.
"You see the other side of that with mitigation action in the United Kingdom and the United States. There's a lot of uncertainty around policy and it's not helping in some ways."
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