Illustration of colorful city with shaded structures and lush trees

The spotlight

Last week, Grist published a special multimedia project exploring the many tools that cities have at their disposal to prepare for one of climate change’s deadliest impacts: extreme heat.

The topic has been a central focus for us throughout the summer, both here in Looking Forward and for the full Grist newsroom, with the launch of our Record High series. And it’s been a summer (or winter, in the Southern Hemisphere) of scary news, with records smashed and new studies about where humans may not be able to survive as the world continues to warm.

But as we’ve discussed in this newsletter, promising adaptations to extreme heat abound, and many cities and towns are already planning for a hotter future and implementing life-saving measures like cool roofs, green corridors, and tree-equity plans. Early on in Grist’s planning for a summer of extreme heat coverage, Jake Bittle was interested in taking a comprehensive look at the solutions that are out there. Meanwhile, Naveena Sadasivam wanted to explore how cities in the hottest parts of the world have harnessed clever design principles to keep cool.

“We were like, ‘What if we just did a thing about how to redesign an entire city for heat?’” Jake recalls. The result: a multimedia project that envisions a combination of heat-proofing strategies used together to build more resilient — and low-carbon — living spaces.

The pair teamed up and reached out to city planners, architects, and other experts to get a full picture of the landscape of heat solutions — and they and their editors quickly decided that the project should be a visual one. They collaborated with artist Florencia Fuertes to help bring the solutions into full view.

The finished product examines different heat-proofing measures grouped by the types of locations where they would be implemented: city centers, residential areas, or commercial zones. And for each, you can explore a futuristic rendering of what an area could look like if it were heat-proofed to the fullest extent.

Check out the project here.

Throughout the reporting, a few themes emerged. “People kept saying over and over again, ‘You don’t have to find a bespoke and crazy gizmo for each part of the urban environment,’” Jake says.

The principles of shade, green space, water, airflow, and good insulation and energy-efficiency in buildings were repeatedly mentioned — things that generally are not that hard or high-tech, and often come with additional benefits besides cooling. But while adding shade and plants and maximizing energy efficiency may seem straightforward, they’re still interventions that require planning and resources.

“The challenge is in the implementation,” Naveena says, adding that “a lot of these solutions have to be tailored to the geographic location — the specific city or community or neighborhood that you’re talking about.” For instance, in a desert city like Phoenix, relying on water to help keep cool wouldn’t make the most sense. Paris, on the other hand, found a cooling solution in a network of pipes that draw cold water from the Seine River to buildings throughout the city.

Although heat-proofing will take time — and money — Jake and Naveena found that the experts they spoke to shared a great amount of consensus around the solutions. Compared with other climate issues, like flooding, wildfires, or decarbonization, they didn’t find much debate or controversy about what needs to be done to better prepare cities for extreme heat, which they said was encouraging.

We’ve excerpted just a few of the solutions that Jake and Naveena found most interesting throughout their reporting. You can explore many more, along with 360-degree views of what they could look like all together, here.

— Claire Elise Thompson

. . .

Cooling towers stick up above a cluster of buildings, illustrated by Florencia Fuertes.

  1. SHADED STRUCTURES: Waiting 20 minutes for the bus in triple-digit weather isn’t just unpleasant — it can be dangerous. Bus stops, train stations, and other outdoor transit facilities are some of the biggest heat pinch points in the urban environment. The easiest way to address this risk is to install shade structures. But urban planners told Grist communities need to make sure these are big enough to fit more than a person or two if they hope to increase ridership: Earlier this year, Los Angeles debuted a prototype called La Sombrita, which was designed to provide shade to people at bus stops in places where the city couldn’t build full shelters. But the structure was so skinny that it couldn’t block out the sun for more than one person at a time.
  2. COOLING TOWERS: Wind catchers, tall chimney-like towers attached to the sides of homes and buildings, are great passive cooling systems and make use of pressure differences within a building to increase ventilation. These “Barjeel” towers are a common sight in the United Arab Emirates and other Gulf countries. Air entering the building is cooled down through wet cloths; warmer air inside the structure rises and escapes through towers. The wind catchers are typically four-sided, although cylindrical, hexahedral, and tetrahedral towers also exist. A variation of this idea is the solar chimney, which has been around for centuries. A chimney structure made with heat-absorbing materials such as glass or metals is used to heat a specific section of air within a building. As the hot air rises, it creates a natural vertical ventilation flow that circulates cool air.
  3. WASTE HEAT CAPTURE: In addition to creating a large buffer around industrial facilities, companies can also cut down on waste heat by investing in heat capture technology. A heat exchanger at a big factory can suck up leaking heat and cycle it back into the facility, which also cuts down on energy demand. This capture can make a building more energy-efficient by capturing the 20 to 50 percent of energy that gets wasted as heat. One estimate from the Environmental Protection Agency suggests that catching the usable waste heat in the U.S. could generate 7.6 gigawatts of power, enough juice for millions of homes.

Read more about heat solutions from Grist’s Jake Bittle and Naveena Sadasivam here.

More exposure

A parting shot

Another solution that Jake and Naveena found was green walls — a concept similar to green roofs that involves covering the walls of tall buildings with ivy or other plants that block the sun’s rays and help to keep the outside air tool. They also add beautification. Here’s an example in Tokyo, Japan.

A view of the facade of a building with moss and vines creeping up it.