PHOENIX – Warmer is the new normal in Phoenix.
According to the recently updated average temperatures, we’ve seen a warming trend in both our daytime and nighttime temperatures.
At night we know it’s a combination of Climate change and urban development this affects the low temperatures overnight.
In addition to reducing greenhouse gases, weakening the urban heat island could help slow the trend of rising temperatures. Right here in the Valley, research is being carried out to test new technologies that could have a decisive influence on the cooling of our cities in the future.
That’s the idea behind a stretch of street in the Garfield District, south of downtown Phoenix.
It is one of eight neighborhoods in the Valley where an asphalt sealing product called CoolSeal from the manufacturer GuardTop is being tested as a method to mitigate the heat island effect.
Jennifer Vanos is an Assistant Professor at Arizona State University. The goal of the CoolSeal is to reflect the sun’s energy back into space so that the heat is not absorbed by the asphalt as would normally be the case with conventional sealants.
“No city has tried it the way Phoenix has tried, and that’s why we’re really a world leader in this area,” says Vanos.
This research examines the benefits and potential effects of this product. So far, they have found that the surface temperature of the asphalt coated with CoolSeal is 16 degrees Fahrenheit lower than that of the asphalt covered with conventional seals.
The air temperature over the asphalt is also about 4.4 degrees Fahrenheit cooler.
“That doesn’t sound like a lot, and it’s not necessarily something our bodies could feel, but one of our goals for the coming year is to take these numbers for each neighborhood and do calculations of what” that means in terms of energy use what this means for water consumption and what it potentially means for human health, ”explains Vanos.
David Sailor is director of urban climate research at ASU. He says the CoolSeal can help reduce the amount of solar energy absorbed, but there’s also new technology that could cool the surrounding air even further.
Known as “passive radiant cooling material,” it reflects and radiates energy so that the surface is actually cooler than the air temperature at all times, explains Sailor.
“It’s kind of a game changer in the ability to cool our cities, because even a white surface on a roof, as we overlook it here, still stays a bit hotter than the air temperature during the day, adding warmth to the environment, not like that much like a dark surface but they add warmth. If we replace this white surface with a passive radiant cooling surface, it would actually always be below the air temperature and that would enable us to cool the environment further, ”says Sailor.
Innovations like these could also make it possible to implement heat island mitigation strategies on a larger scale, even within our own four walls. These technologies are available in darker colors so that you could benefit from the cooling effects without necessarily having to have a white or light roof.
While not all of these technologies are out on the market yet, Sailor says that now is the time to view them as part of the infrastructure of the future.
“We have our fate in our own hands, let’s use that and the more we make our cities more livable, flourishing communities, the better we protect ourselves from the danger of fleeing our cities,” says Sailor.
Sailor adds that while these technologies could really make a difference in how we experience and mitigate the heat here in the Valley, it is important to always consider not only the benefits but also the negative effects that they could bring so that we can make informed decisions as our city grows and develops.