Author | Raquel C. Pico
High temperatures are no longer a problem confined to summer or specific regions of the world. Climate change has intensified extreme heat, exposing people to high temperatures for more hours each day and more days each year. Cities have become particularly vulnerable, as the way they are built has created urban heat islands. Climate adaptation therefore requires rethinking urban design and introducing cooling solutions that help reduce perceived temperatures.
Reflective pavements, also known as cool pavements, are one such solution. These pavements replace conventional surfaces with a specific goal: to help regulate temperatures. Because they reflect more sunlight than traditional asphalt, they absorb and retain less heat. As a result, they also release less heat at night, helping to lower urban temperatures.
This is one of the major challenges facing cooling systems designed to improve heat management and urban resilience. The materials and infrastructure used throughout the 20th century retain heat, meaning that during periods of extreme heat, city residents get little relief even after nightfall.
How Phoenix developed its cooling system
Phoenix (United States) is one of the cities experimenting with these systems. In 2020, the city launched a project to introduce cool pavements in areas across eight neighborhoods. The project began in areas that were already due for resurfacing, but instead of using conventional asphalt, the city opted for this new approach. In Phoenix, the system uses a reflective gray surface coating containing titanium dioxide to help manage heat by reducing absorption.
What makes Phoenix’s approach particularly interesting is that, from the outset, the city decided to support the project with a parallel scientific study. It partnered with Arizona State University from the beginning to monitor the process and determine whether it was actually having a positive impact, as well as identify any potential shortcomings. University researchers conducted two studies at different stages of the resurfacing project.
The first was conducted after one year, when researchers confirmed that the reflective pavement was indeed functioning as a cooling system. The primary goal of reducing heat released at night had been achieved, and the pavement itself was cooler than conventional asphalt during peak sunlight hours. However, one challenge for climate adaptation emerged: at midday, pedestrians experienced slightly higher temperatures, although the perceived heat was comparable to walking along a conventionally paved street.
The second study was conducted in 2024 and found that average surface temperatures were lower than in areas without cool pavement treatments, with a beneficial effect on air temperatures as well. Researchers also found that street maintenance costs were lower.
Phoenix (United States) is one of the cities experimenting with these systems. In 2020, the city launched a project to introduce cool pavements in areas across eight neighborhoods. The project began in areas that were already due for resurfacing, but instead of using conventional asphalt, the city opted for this new approach. In Phoenix, the system uses a reflective gray surface coating containing titanium dioxide to help manage heat by reducing absorption.
What makes Phoenix’s approach particularly interesting is that, from the outset, the city decided to support the project with a parallel scientific study. It partnered with Arizona State University from the beginning to monitor the process and determine whether it was actually having a positive impact, as well as identify any potential shortcomings. University researchers conducted two studies at different stages of the resurfacing project.
The first was conducted after one year, when researchers confirmed that the reflective pavement was indeed functioning as a cooling system. The primary goal of reducing heat released at night had been achieved, and the pavement itself was cooler than conventional asphalt during peak sunlight hours. However, one challenge for climate adaptation emerged: at midday, pedestrians experienced slightly higher temperatures, although the perceived heat was comparable to walking along a conventionally paved street.
The second study was conducted in 2024 and found that average surface temperatures were lower than in areas without cool pavement treatments, with a beneficial effect on air temperatures as well. Researchers also found that street maintenance costs were lower.
Other examples of reflective pavement
Phoenix is not the only city exploring this approach. Climate adaptation projects are emerging in several countries. In 2025, Barcelona also launched a pilot project using reflective pavement on one of its streets. The city is developing a holistic strategy that involves replacing conventional asphalt with more environmentally conscious solutions. This pilot project is one example, alongside efforts to make the city greener and create climate shelters. Europe has just experienced its hottest summer on record, making the need to reduce urban heat islands more pressing than ever.
In fact, reflective pavements are part of a much broader shift that also includes the permeable or porous pavements being adopted by an increasing number of cities. Sponge parks and green walkways are gaining traction, as is the use of alternative materials such as living concrete. Even something as simple as painting surfaces in lighter colors is becoming an increasingly important strategy for tackling extreme heat.
Phoenix is not the only city exploring this approach. Climate adaptation projects are emerging in several countries. In 2025, Barcelona also launched a pilot project using reflective pavement on one of its streets. The city is developing a holistic strategy that involves replacing conventional asphalt with more environmentally conscious solutions. This pilot project is one example, alongside efforts to make the city greener and create climate shelters. Europe has just experienced its hottest summer on record, making the need to reduce urban heat islands more pressing than ever.
In fact, reflective pavements are part of a much broader shift that also includes the permeable or porous pavements being adopted by an increasing number of cities. Sponge parks and green walkways are gaining traction, as is the use of alternative materials such as living concrete. Even something as simple as painting surfaces in lighter colors is becoming an increasingly important strategy for tackling extreme heat.
Risks of reflective pavements
Nevertheless, determining which cooling systems work best and how to adapt public spaces is not so straightforward. Extreme heat is a complex problem, and reflective pavements are not a cure-all, although they can make a significant difference. Phoenix residents have told local media that they do not always feel cooler when walking on reflective pavement or notice much of a difference. However, they do confirm that temperatures drop at night, allowing them to enjoy their streets.
Nevertheless, determining which cooling systems work best and how to adapt public spaces is not so straightforward. Extreme heat is a complex problem, and reflective pavements are not a cure-all, although they can make a significant difference. Phoenix residents have told local media that they do not always feel cooler when walking on reflective pavement or notice much of a difference. However, they do confirm that temperatures drop at night, allowing them to enjoy their streets.
Frequently Asked Questions
- What are reflective pavements?
These pavements reflect sunlight and therefore absorb less heat.
- What has Phoenix done?
The city has resurfaced areas in several neighborhoods with reflective pavement to lower temperatures and reduce urban heat islands.
- Are there places where this cooling system works better?
Some studies suggest that reflective pavement may be particularly suitable for areas such as large parking lots and unshaded spaces, rather than areas with heavy pedestrian traffic.
- What are reflective pavements?
These pavements reflect sunlight and therefore absorb less heat.
- What has Phoenix done?
The city has resurfaced areas in several neighborhoods with reflective pavement to lower temperatures and reduce urban heat islands.
- Are there places where this cooling system works better?
Some studies suggest that reflective pavement may be particularly suitable for areas such as large parking lots and unshaded spaces, rather than areas with heavy pedestrian traffic.
Fonte: Tomorrow Cities
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