Help cities around the world prepare for extreme heat


With a few weeks to go, the summer of 2022 has already passed alarming milestones.

As India sweltered ahead of the monsoon, temperatures in parts of New Delhi exceeded 49 degrees Celsius (120 degrees Fahrenheit). In the United States, millions endured an almost unprecedented combination of heat and high humidity throughout July, while in wildfire-hit Europe, even Britain issued its first ‘red’ warning, with London exceeding 40 degrees. Globally, June and July this year ranked among the hottest months on record.

Unfortunately, these trends are likely to worsen, in part due to global warming. In India and Pakistan, a study suggested that extreme heat is 30 times more likely due to climate change. Summer days in Britain could exceed 40 degrees once every 3.5 years by 2100 – instead of once every 100 to 300 years – if greenhouse gas emissions are not not reduced.

Partly because of bad policy, the world’s sprawling urban centers – where black tarmac and concrete soak up heat and suffocate air pollution – will likely bear the brunt of this crisis. European cities already experience twice as many heatwave days as their rural surroundings. Even in temperate regions of the world, urban areas experience weather conditions that threaten livelihoods; when it’s not killing, “urban heat stress” makes the job much harder.

Without radical action to change our lives and our cities, the threats to health and economic productivity will only grow. So how can the world prepare for the hotter summers to come?

The most important step is to continue the broader fight against global warming, including reducing emissions, stimulating investment in green energy and related technologies, imposing higher prices on carbon and financing research into potential breakthrough technologies, such as carbon capture and nuclear fusion. .

Beyond that, it is essential to better measure the problem. That means considering not just temperature, but also aggravating factors like humidity, which can lower human tolerance for sweltering weather by making it harder to sweat and chill. It also means understanding local conditions in more detail, such as the extent to which the heat decreases at night, how weather patterns vary over time, and how higher temperatures affect specific urban environments. Seville, Spain, in collaboration with the Adrienne Arsht-Rockefeller Foundation Resilience Center, is already using these methods to classify heat waves, linking specific measures to each, and naming them, like hurricanes, to highlight the hazards.

Measures to help the poor should also be a priority. The less affluent, who are more likely to work outdoors and less likely to have air-conditioned homes, tend to suffer the most from extreme heat. The solutions can be simple: in Freetown, Sierra Leone, the city’s heat chief has introduced awnings to shelter women in open-air markets and plans to add urban gardens and cooling centres. Medellin, Colombia has used green corridors to successfully reduce the “heat island” effect, in which the built environment absorbs energy from the sun and intensifies local heat.

This kind of thinking will be essential as urban areas around the world try to adapt. Cities will need to plant more trees and make better use of waterways; build more resilient infrastructure to prevent buckling of rails and melting of tracks; impose greener buildings and better insulation; and require more efficient air conditioning units and fans. They should adopt smart grid technologies to help reduce energy losses, integrate clean energy and manage peak demand. Above all, they should experiment with new ideas to make city life more bearable for the hot summers ahead.

Several of these steps are underway. Hopefully the scorching heat this summer will only underscore the urgency for action.

More other writers at Bloomberg Opinion:

• When the weather is hot enough to kill: David Fickling and Ruth Pollard

• Britain is burning. India knows how to cool down: Mihir Sharma

• European drought offers an energy gift to Putin: Javier Blas

The editors are members of the Bloomberg Opinion Editorial Board.

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