skip to main content
skip to newscasts

Tuesday, July 23, 2024

Public News Service Logo
facebook instagram linkedin reddit youtube twitter
view newscast page
play newscast audioPlay

Gov. Whitmer endorses Kamala Harris for president, says she's not leaving Michigan; Grilled by lawmakers on the Trump assassination attempt, Secret Service director says, 'We failed;' Teachers rally at national convention in Houston; Opioid settlement fund fuels anti-addiction battle in Indiana; Nonprofit agency says corporate donations keep programs going.

view newscast page
play newscast audioPlay

Democrats consolidate support behind Vice President Harris, Republicans threaten legal action over changes to the presidential ticket, and a possible bipartisan consensus forms on the failure of the Secret Service to protect former President Trump.

view newscast page
play newscast audioPlay

It's grass-cutting season and with it, rural lawn mower races, Montana's drive-thru blood project is easing shortages, rural Americans spend more on food when transportation costs are tallied, and a lack of good childcare is thwarting rural business owners.

'Cool pavement' coating helps CA city beat the heat

play audio
Play

Tuesday, June 4, 2024   

By Ysabelle Kempe for Smart Cities Dive.
Broadcast version by Suzanne Potter for California News Service reporting for the Solutions Journalism Network-Public News Service Collaboration


Reflective pavement coating helped cool down one of Los Angeles' hottest neighborhoods over a year-long period, according to a recently published study in Environmental Research Communications, but some researchers argue in favor of increasing shade as a better way to protect people from dangerously high temperatures.

The research on the installation in LA's Pacoima neighborhood is "probably the most comprehensive study on controlled cool pavement" due to the large amount of data and variables considered, said Haider Taha, an atmospheric modeler, president of the research company Altostratus and the study's author.

Over 700,000 square feet of dark asphalt surfaces in Pacoima were covered with solar-reflective pavement coating in the summer of 2022 through a partnership between local nonprofit Climate Resolve and roofing and waterproofing manufacturer GAF, which provided the coating.

Pavement that reflects, rather than absorbs sunlight, has emerged as a tool cities are considering to mitigate theincreasing danger of extreme heat.

GAF funded the recently released peer-reviewed study, although the company had no role in the study's design, data collection, modeling or analysis of the results. The research found that during an extreme heat event, the cool pavement-covered area saw ambient air temperatures that were as much as 3.5 degrees Fahrenheit cooler than those in the adjacent neighborhood. On sunny days, ambient air temperatures were reduced by up to 2.1 degrees Fahrenheit. During summer nights, they were reduced by up to 0.5 degrees Fahrenheit. The coating also lowered surface temperatures by up to around 10 degrees Fahrenheit.

What does that mean for the people who live in Pacoima? Melanie Torres, a resident and the Pacoima Beautiful's Cool Community Project organizing manager, said she's felt a difference. Pacoima Beautiful is a local environmental justice organization and helped GAF and Climate Resolve with community engagement for the reflective pavement project.

Torres often eats lunch in one of the parks where the coating is deployed. "I can just sit on the grass near the basketball court and feel just the breeze - and not necessarily a hot breeze," she said. A food vendor who frequents the neighborhood told Torres that "she feels the difference in the breeze more than anything.

Torres said she hasn't heard any complaints about the reflective pavement coating during her community engagement efforts. However, reflective pavement is not immune to criticism.

Some researchers have found that the solar energy reflected off cool pavement can actually increase how hot pedestrians feel. Taha, however, said that his study indicated an "improvement in thermal sensation," noting that every location within Pacoima has "its own dynamics" that could lead to slightly different results. Mean radiant temperature - a measurement of thermal comfort - "goes up and down. It's not always cooler," he said. "The overwhelming effect is the cooling."

But no matter how effective reflective coatings are, they can't beat shade, V. Kelly Turner, associate director of the University of California, Los Angeles' Luskin Center for Innovation and an associate professor of urban planning and geography, said in an email. Shade can cool people by up to 30 degrees Celsius, or 54 degrees Fahrenheit, in hot, dry environments, she said.

"No change in surface will protect the body from heat as effectively as preventing sunlight from hitting the body in the first place," she said. "Shade - blocking the sun with trees, canopies, and tall features like walls and buildings - is by far the most effective way to cool people outdoors."

She noted that reflective pavement doesn't have a large effect on air temperature unless it is deployed widely and, even when that happens, the cooling benefit is moderate. She believes that reflective pavement is an appropriate choice in locations where it would be difficult to replace surfaces that absorb a lot of heat with "something else like vegetation and where the goal of mitigating surface material contributions to heat is the priority as opposed to protecting people's bodies outdoors."

"I think cities should see reflective pavement as one tool among many, if deployed comprehensively, that could mitigate the regional urban heat island," Turner said. "They should see this goal as parsimonious from the public health goal of protecting people's bodies from the sun."


Ysabelle Kempe wrote this article for Smart Cities Dive.


get more stories like this via email

more stories
Maryland has more than 750,000 renter households, representing 33% of all households in the state. (Adobe Stock)

Social Issues

play sound

With rising housing costs an ongoing issue, a new report shows how fast rents have increased in Maryland and nationwide. The National Low Income …


Environment

play sound

The federal Bureau of Land Management has published a new plan for managing public lands which will put oil and gas management in sync with Colorado's…

Social Issues

play sound

More than 60 million Americans identify as disabled and many of them turn to nonprofit agencies such as Easterseals for therapy and other assistance…


Nationwide statistics show while overall reported hate crimes decreased by about 7% in 2023 compared to 2022, hate crime events motivated by sexual orientation bias increased 3.6%.(Anastasiia/Adobe Stock)

Social Issues

play sound

Hate crimes against members of the LGBTQ+ community have risen for the second year in a row, according to the latest "State of Pride" report from the …

Social Issues

play sound

After a historic weekend, politics turned out to be the major topic Monday at the national convention of more than 3,500 teachers union members…

The United States has 403 centers for independent living, according to the National Council on Independent Living. (Adobe Stock)

Health and Wellness

play sound

Advocates for individuals with disabilities want the state of Nevada to further embrace what is known as the "independent living" model. Dawn Lyons…

Environment

play sound

As the Atlantic coast braces for what could be an active hurricane season, environmental groups are warning about the dangers of agricultural …

Social Issues

play sound

Civic organizations with ideas for improving their communities have a new opportunity to turn their ideas into reality, thanks to recently awarded …

 

Phone: 303.448.9105 Toll Free: 888.891.9416 Fax: 208.247.1830 Your trusted member- and audience-supported news source since 1996 Copyright 2021