New report tackles a pollution puzzle: while other pollutants drop on weekends, smog-causing ozone levels actually increase over the weekend in certain parts of California.
In the Los Angeles area, ozone levels typically are 32 percent higher on Saturdays and Sundays than they are Monday through Friday when freeways are clogged with commuters. The difference is 25percent in San Francisco. The phenomenon in Los Angeles and San Francisco, first noticed in the 1980s, has four possible explanations, according to the report.
Thanks to Abhijeet Chavan
FULL STORY: Report cites several reasons for weekend smog increase

Maui's Vacation Rental Debate Turns Ugly
Verbal attacks, misinformation campaigns and fistfights plague a high-stakes debate to convert thousands of vacation rentals into long-term housing.

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

In Urban Planning, AI Prompting Could be the New Design Thinking
Creativity has long been key to great urban design. What if we see AI as our new creative partner?

Portland Raises Parking Fees to Pay for Street Maintenance
The city is struggling to bridge a massive budget gap at the Bureau of Transportation, which largely depleted its reserves during the Civd-19 pandemic.

Spokane Mayor Introduces Housing Reforms Package
Mayor Lisa Brown’s proposals include deferring or waiving some development fees to encourage more affordable housing development.

Houston Mayor Kills Another Bike Lane
The mayor rejected a proposed bike lane in the Montrose district in keeping with his pledge to maintain car lanes.
Urban Design for Planners 1: Software Tools
This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.
Planning for Universal Design
Learn the tools for implementing Universal Design in planning regulations.
Gallatin County Department of Planning & Community Development
Heyer Gruel & Associates PA
JM Goldson LLC
City of Camden Redevelopment Agency
City of Astoria
Transportation Research & Education Center (TREC) at Portland State University
Jefferson Parish Government
Camden Redevelopment Agency
City of Claremont