Research shows that road asphalt exposed to heat and sunlight may eventually become a significant emissions source.

A new study reports that asphalt emits significant amounts of pollutants in hot conditions. "[Researchers] observed that asphalt emissions doubled when the temperature increased from 40C to 60C — levels the material often reaches in summer," reports Rhi Storer.
When road asphalt was exposed to both solar radiation and heat, to mimic outdoor summer conditions, the researchers found a 300 percent increase in emissions. The release of secondary organic aerosols has been shown to have public health impacts, notes Storer.
While most traffic-related pollution comes from vehicle sources, the impact of cars and trucks may decrease as gross polluters are phased out. As a result, asphalt emissions may contribute more to air pollution as urban areas grow—45 percent of the surface area in the United States is paved—and temperatures rise due to climate change.
FULL STORY: Asphalt roads make city air pollution worse in summer, study finds

Eugene Ends Parking Minimums
In a move that complies with a state law aimed at reducing transportation emissions, Eugene amended its parking rules to eliminate minimum requirements and set maximum parking lot sizes.

How Paris, Texas Became a ‘Unicorn’ for Rural Transit
A robust coalition of advocates in the town of 25,000 brought together the funding and resources to launch a popular bus service that some residents see as a mobility lifeline—and a social club.

San Diegans at Odds Over ‘Granny Towers’
A provision in the city’s ADU ordinance allows developers to build an essentially unlimited number of units on single-family lots.

New York Strengthens Protections for Mobile Home Park Residents
Modular home owners will get the first right of refusal when park owners want to sell residential parks.

Palo Alto Expands Church ‘Safe Parking’ Program
The city is considering adding commercial lots to the program, which provides safe parking and amenities for people living in cars.

Report: California’s Orphan Wells Still Pose Health Risks
Tens of thousands of idle oil wells litter the state. Taxpayers are often on the hook for cleanup.
HUD's Office of Policy Development and Research
HUD's Office of Policy Development and Research
Chaddick Institute at DePaul University
Park City Municipal Corporation
National Capital Planning Commission
City of Santa Fe, New Mexico
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