Dealing with this key in of heat requires more than isolated interventions reflective roofs here or mist machines there.
SHADED STRUCTURES: Waiting 20 minutes for the bus in triple-digit weather isnt just unpleasant it can be dangerous.
The easiest way to address this risk is to install shade structures.
Illustration: Florencia Fuertes / Grist
During the summertime, the area below a tree receives just 10 to 30 percent of the suns energy.
Whats more, trees come with other benefits, like improving air quality and reducing runoff.
To reverse this discrimination, many cities are targeting their tree-planting campaigns toward these neighborhoods.
Illustration: Florencia Fuertes / Grist
MISTERS: Even with shade structures available, bus stops and public plazas can still be overwhelmingly hot.
COOL PAVEMENT: Ever walked across a parking lot and felt the heat burn through your shoes?
Pavements heat up when they absorb energy from the sun.
Illustration: Florencia Fuertes / Grist
Others use resin from trees as binders.
Porous asphalt, rubberized asphalt, and bricks made from clay also increase reflectivity and porosity.
These pavements are also often painted in light colors that reflect more heat.
Illustration: Florencia Fuertes / Grist
But cool pavements have one major downside.
High-rise buildings block sunlight and create canyons or passages that are cooler than surrounding areas during the day.
Theyre commonly found in markets and historic centers in Middle Eastern cities.
Urban planners in Abu Dhabi employed sikkak to increase connectivity within larger blocks.
If pointed to the ground, the reflected sunlight and its heat can make conditions worse.
GREEN WALLS: Skyscrapers themselves absorb a lot of sun, and keeping them cool can be challenging.
Foliage-covered structures have become prevalent in Middle Eastern cities like Tel Aviv.
This effect is even more powerful when combined with trees that blunt the suns heat.
Residential Areas
But most American space is not high-rise.
That is the future, said Turner.
Shade structures like awnings or overhangs and reflective coatings can help keep the heat out.
While these smart windows are available on the market, they can be cost-prohibitive for most homeowners.
Known as Barjeel towers, they are a common sight in the United Arab Emirates and other Gulf countries.
The wind catchers are typically four-sided, although cylindrical, hexahedral, and tetrahedral towersalso exist.
A variation of this idea is the solar chimney, which has been around for centuries.
As the hot air rises, it creates anatural vertical ventilation flowthat circulates cool air.
A growing number ofcities already have cool roof requirementsin their building codes.
From a market perspective, its a no brainer.
Whether natural or built, shade can dramatically lower temperatures and create a much safer play environment for children.
In Jackson, Mississippi,two moms designedcanopies that cover 75 percent of a local playground.
The shade sails also have an added benefit: protection from ultraviolet rays.
Its like wearing sunscreen without having to wear it, one of the momstold a local TV station.
When these materials are shaped into blocks with air pockets, theyre particularly good at providing thermal insulation.
Air is a poor conductor of heat, and air cavities in building materials can prevent heat penetration.
Paraffinic waxes and different types of salt hydrates are somecommon types of phase-change materials.
The same is true for manufacturing areas, where power plants and factories also leak heat into surrounding streets.
BUFFER ZONES: Factories run huge generators at all hours of the day, pouring heat onto surrounding streets.
Power plants combust natural gas in the heat of summer to power air conditioners across the city.
Semitrucks idle on big trucking routes and depots, burning diesel as they stand still.
All of this industrial activity generates waste heat.
Experts say the best way to mitigate this heat is through good urban design.
PUBLIC TRANSIT: The way we design transportation systems is key to combating high temperatures.
A car-choked thoroughfare produces much more of what researchers call waste heat than a tram or bus lane.
Land use and urban development patterns matter, said Meerow.
In addition, these systems need to have reliable service.
But theres a win-win option available: Cover these lots with solar panels that double as shade structures.
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