Weekend Ozone Effect

Many cities have higher ozone levels on weekends even though nitrogen oxide (NOx) emissions go down 10 to 40 percent on weekends.

1 minute read

August 27, 2003, 7:00 AM PDT

By Chris Steins @planetizen


"...Under the right conditions -- conditions that now exist in many American cities -- reducing NOx can actually make ozone worse. This is challenge enough for areas trying to comply with EPA's tough new eight-hour ozone standard. But EPA and the California Air Resources Board (CARB) are compounding the problem by making believe it doesn't exist. Indeed, despite the risks, during the last few years these agencies have promulgated regulations specifically intended to achieve large, nationwide NOx reductions. These regulations will cost billions of dollars per year, but risk worsening smog for millions of Americans... Americans deserve regulations based on rigorous science that deliver net benefits to their welfare. It's unfortunate that environmental regulatory agencies are falling short on both of these key goals."

Thanks to PreservingtheAmericanDream Listserv

Tuesday, August 26, 2003 in Tech Central Station

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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