Asia to blame for calif. Smog----what are we going to do about that? NOTHING

While domestic emissions of ozone — the main constituent of smog — have been declining in recent years, as much as 20 percent of California’s smog may now be coming from China and other Asian countries, according to new research.

“Rather than imposing enormously expensive new restrictions on American emissions of ozone, as the Environmental Protection Agency has proposed, perhaps it is time to look across the Pacific for more cost-effective ways to clear the air,” say researchers at the Reason Foundation.

Since 1980, average levels of ozone have declined by 25 percent nationally and by more than 60 percent in Los Angeles, according to the EPA. Much of the decline is due to regulations limiting emissions of ozone-forming chemicals by vehicles and industry.

But a “significant” proportion of ozone on the West Coast now comes from Asia, researchers Julian Morris and Adam Peshek point out.

They cite a recent study published in the Journal of Geophysical Research showing that in spring, low pressure systems in Asia can cause ozone produced there to rise two to six miles into the atmosphere. It is blown across the Pacific by strong winds, then pulled back down to ground level by high-pressure systems in the northeastern Pacific.

The study found that Asian emissions produced 8 to 15 parts per billion (ppb) of ozone in California in the spring of 2010, accounting for about half the days when the state was not in compliance with the EPA’s threshold of 75 ppb.

The EPA had actually planned to lower the threshold to between 60 and 70 ppb. President Obama, under pressure from U.S. businesses, scrapped the plan. But the EPA is now conducting a review of ozone and could impose a lower level as early as next year.

Such a move would have a costly impact on manufacturing, construction, trucking, farming, electric utilities and other American industries, the researchers note.

They conclude: “To the extent that the ozone problem is now being imported from Asia, instead of focusing exclusively on domestic emissions, it might make sense to look at ways of encouraging China, Thailand, Vietnam, and other culprit countries to reduce their emissions.”