China’s export industry is responsible for dirty emissions that are blowing across the Pacific Ocean and contributing to smog in the United States, a new scientific study says. 
 
 About one-fifth of the pollution China spews into the atmosphere comes from producing goods for export to the United States and other countries, according to the paper by a group of scientists that was published Monday in the Proceedings of the National Academy of Sciences. Winds blow pollutants from Chinese power plants and factories across the Pacific in about six days, where they boost levels of smog in the United States. 
 
 Los Angeles and parts of the eastern U.S. experienced at least one extra day of smog that exceeded federal health standards for ozone in 2006 as a result of emissions from export manufacturing in China, the study found. 
 
 “Rising emissions produced in China are a key reason global emissions of air pollutants have remained at a high level during 2000–2009 even as emissions produced in the United States, Europe, and Japan have decreased,” the scientists wrote. “Outsourcing production to China does not always relieve consumers in the United States — or, for that matter, many countries in the Northern Hemisphere — from the environmental impacts of air pollution." 
 
 Nine scientists in the United States, China and the United Kingdom used data from 2006 to quantify how much of the air pollution reaching the U.S. West Coast from China is from the production goods for export to the United States and other countries. Scientists followed the path of air pollutants, including sulfur dioxide, nitrogen oxides carbon monoxide and black carbon, through the atmosphere to gauge their effects on air quality in the United States. 
 
 While the United States has reaped some of the benefits of outsourcing -- cheaper cellphones, televisions and appliances and big declines in air pollution -- rising emissions in China have paralyzed cities there with severe smog. 
 
 The paper is a reminder that U.S. demand for cheap imports from China has a way of blowing those environmental problems back at us, said Steve Davis, an Earth system scientist at UC Irvine and co-author of the study. 
 
 “It’s sort of a boomerang effect,” he said. 
 
 Davis expressed hope that the findings would be used by world governments working to craft international agreements to limit emissions of carbon dioxide that are driving climate change as well as short-lived air pollutants that are responsible for poor air quality around the globe. 
 
 “We need to move beyond placing blame for who’s creating these emissions and realize that we all have a common interest in reducing the pollution,” Davis said. 
 
 Since the 1990s, scientists have known that pollution from China is carried across the Pacific by westerly winds and that it worsens air quality along the U.S. West Coast. Those emissions contribute only slightly to U.S. smog levels, which are overwhelmingly caused by local emissions from vehicles, factories and power plants. 
 
 “We shouldn’t take an alarmist perspective,” Davis said. “Los Angeles air quality is not going to be what it was in the 70s or 80s because of this.” 
 
 tony.barboza@latimes.com 
 
 Twitter: @tonybarboza ||||| Chinese are growing more outspoken about the "fog," now accurately calling it "smog," covering cities like Beijing. 
 
 BEIJING—While China’s chief climate negotiator is getting rock star treatment at the Durban climate summit this week, his peers back in the capital are suffering a third straight day of foul air. 
 
 As a leading Canadian newspaper put it, China provided “the few glimmers of hope at the stalled negotiations” in Durban, where "photographers and television journalists swarmed around the chief Chinese negotiator, Xie Zhenhua, as he entered a news conference on Monday to announce his list of conditions for considering a legally binding treaty on carbon emissions after 2020." 
 
 It seems that despite being the world's biggest carbon emitter, China could be the key to a deal on a legally binding agreement to reduce emissions. 
 
 However, not many glimmers of hope could be spotted back home. 
 
 From the China Daily website A grid image posted on the China Daily newspaper showing the dramatic changes in air quality in Beijing in the past four days. 
 
 A persistent 'fog' 
 
 The Chinese state-run print media all ran headline stories Tuesday morning on the persistent "fog" that has blanketed Beijing and parts of the country’s northeast since the weekend. (See video above of the "hazardous" level of smog on Monday). 
 
 Much of the coverage focused on the hundreds of flights cancelled at the Beijing Capital International airport—the world’s second busiest hub—or the rising and very vocal concerns about air pollution. Some local reports referred to sales of air filter masks and air filter machines spiking in the past week. 
 
 Still more reports tried to cast the air pollution issue as one of sovereignty. "The heavy fog or smog that has shrouded Beijing in the past couple of days has triggered a renewed round of debate over the different air pollution standards applied by China and the United States," said an opinion piece in the Global Times, a state-run newspaper with a strong nationalist overtone. 
 
 But at least these same newspapers are now calling it "smog" rather than "fog," as they were just a day ago. The China Daily, another state-run newspaper, ran a headline on page 3 crying, "Exposure to smog is severe hazard." Later in the day, the paper’s web site posted four stark images of the same location showing changes in air visibility. (See photo above). The images are pretty staggering. 
 
 Only 13 days of 'good' air this year so far 
 
 And as we write this, the ever-trusty and ever-reliable @BeijingAir Twitter feed has been down five hours, prompting followers to wonder whether the pollution has finally gotten to the air quality index monitor that lives on top of the U.S. Embassy in Beijing. 
 
 Post by @TomVandeWeghe An image of an iPhone app circulating on Twitter this afternoon, showing the @BeijingAir monitor out of commission. 
 
 A sobering analysis of the @BeijingAir feed can be found in this post by China Dialogue, which notes that the improvements in air quality claimed by officials at the Beijing Environmental Protection Bureau "are due to irregularities in the monitoring and reporting of air quality – and not to less polluted air." 
 
 Moreover, based on the analysis using the @BeijingAir data, this year there have only been 13 days of "good" air quality. 
 
 Buried further amidst the quantitative data was one more alarming point: "…if Beijing’s fine particulate concentration even reached the polluted levels of Los Angeles, life expectancy may increase by over five years." 
 
 We at NBC News Beijing are trying to claw back a few months to our life span. We have just taken delivery of two air filter machines for the bureau.
– Outsourcing dirty emissions-producing industries to China hasn't improved America's air as much as some might think, a new study finds. Researchers say some of the rising emissions from the manufacturing of China's exports—many of which go to America—are making their way across the Pacific, sometimes pushing smog standards above federal health levels in Los Angeles and even in parts of the eastern US, reports the LA Times. The study shows that American demand for cheap exports can still cause environmental problems at home, one of its authors says. "It’s sort of a boomerang effect," he says. "We need to move beyond placing blame for who’s creating these emissions and realize that we all have a common interest in reducing the pollution." In China, meanwhile, the smog problem has become so dire that a scientist has come up with a plan to clean city air with giant sprinklers attached to skyscrapers, Gizmodo reports. (Though one China paper has argued the smog is good for national security.)