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China is sending detectable levels of pollution to the U.S., but a significant fraction of it results from manufacturing products for American customers

smithsonian.com

The most tangible environmental impact of China's enormous manufacturing industry is very localized: Remarkably bad urban air quality in China that occasionally closes schools, has entrepreneurs selling canned air and has caused an estimated 1.2 million premature deaths.

But air pollution doesn't respect international borders. And a pair of recent studies has demonstrated this in striking fashion, showing that the pollution is likely increasing the strength of cyclones forming over the Pacific Ocean and even spreading detectable levels of contaminants all the way to the Western U.S.

The research on air pollution and Pacific cyclone activity, published today in Nature Communications, involved the use of statistical modeling to calculate the effect of air pollution on overall storm formation trends over the Pacific. The research team, led by Yuan Wang of Texas A&M, created a model to simulate the role of temperature, precipitation, cloud cover and other factors in affecting the strength and frequency of Pacific cyclones.

Then they ran the model under two scenarios: One in which the air over Asia was clean, and one that represented the enormous increases in air pollution in recent years, present in most East Asian countries but led by China, which has some of the highest levels of particulate airbone pollution worldwide.

The dynamics of cloud formation are quite complex, but the study's conclusions were surprisingly straightforward. This air pollution, the model showed, has powerful consequences for cyclone formation, increasing overall precipitation over the Northwest Pacific by 7 percent over what it would be otherwise. The particulate matter, the researchers found, is also producing a regional greenhouse gas effect, siginificantly contributing to climate change.

These findings are, naturally, pretty worrisome. But for U.S. readers, the results of the study on the global spread of Chinese air pollution, published yesterday in the Proceedings of the National Academy of Sciences, might be even more troubling, both because they show the effects of Chinese pollution here in the U.S. and because they trace much of the responsibility back to American consumers, who buy a large proportion of the goods manufactured in China.

The research team, made up of both American and Chinese scientists, also used simulations to determine how much of the particulate matter emitted in China rides a seris of prevailing winds known as Westerlies across the Pacific and enters U.S. airspace. They found that, especially in Western U.S. states, significant amounts of the air pollution present could be traced to China. This was true even though the data they studied came from 2006-since then, air pollution in China has climbed rapidly.

On the days with the strongest Westerlies-which occur most often during the spring-between 12 and 24 percent of the sulfate-based air pollution over the Western U.S. was originally generated in China. That was also true for four to six percent of carbon monoxide and two to five percent of ground-level ozone. As a result, they estimated, in 2006 the Los Angeles area experienced one extra day of ozone levels that exceeded EPA standards for air quality.

But this isn't the whole picture. A significant portion of the goods made in China end up in the U.S. As the researchers note, we've outsourced our manufacturing to China, for a variety of reasons. Many of these involve the global labor market and the costs of production, but others are related to China's overall weaker environmental regulations that allow companies to produce goods more cheaply.

Because of this, it's also important to look at the air pollution over China that was generated to make products for customers in the U.S. and other countries. The researchers did this by calculating how much of Chinese manufacturing fits within this category and how much pollution faced by the Chinese people is a direct result of consumer demands from other countries.

The results aren't pretty. An estimated 36 percent of manmade sulfur dioxide, 27 percent of nitrogen oxide, 22 percent of carbon monoxide and 17 percent of black carbon over China are the result of manufacturing goods for export. About a fifth of each of these was associated with products exported to the U.S. in particular. These pollutants have a range of acute effects on human health and can drive the formation of acid rain.

The lesson of all this? Perhaps that China is responsible for some of the pollution over the U.S., but also the reverse: The American demand for cheap products fuels Chinese pollution in the first place.

"We've outsourced our manufacturing and much of our pollution, but some of it is blowing back across the Pacific to haunt us," Steve Davis of UC Irvine, a co-author, said in a press statement. "Given the complaints about how Chinese pollution is corrupting other countries' air, this paper shows that there may be plenty of blame to go around."

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About Joseph Stromberg

# data[].attributes.attachment_link.title
Air Pollution in China Is Spreading Across the Pacific to the U.S.

# data[].attributes.attachment_link.description
smithsonian.com The most tangible environmental impact of China's enormous manufacturing industry is very localized: Remarkably bad urban air quality in China that occasionally closes schools, has entrepreneurs selling canned air and has caused an estimated 1.2 million premature deaths. But air pollution doesn't respect international borders.

# data[].attributes.attachment_link.provider_name
Sean Gallagher - Photographer, Beijing, China

# data[].attributes.attachment_link.readable_text
get in touch

send me a message

Connect with me

About me

My name is Sean Gallagher, a British photographer and filmmaker who has been based in Asia for over a decade.

From the Tibetan Plateau to the Indonesian archipelago, I often spend months in the field travelling across the continent documenting its most important environmental, social and cultural issues for some of the world's leading news outlets.

I am a 7-time recipient of the Pulitzer Center on Crisis Reporting travel grant, am represented by National Geographic Creative and am a Fellow of the Royal Geographical Society (with IBG).

I graduated in Zoology from university in the United Kingdom and it is my background in science that has led to much of my work being focused on communicating environmental issues through visual storytelling.

I do this by creating photographic, video and multimedia projects that highlight individual's stories from communities that are affected by issues such as desertification, deforestation, pollution, species extinction and climate change.

My distinctive approach to visual storytelling and extensive experience in Asia, allows me to create unique photography and video projects for my editorial and commercial clients.

My work has appeared with editorial outlets including The New York Times, National Geographic News, CNN, The Atlantic and BBC News.

I have received a number of awards and grants for my work, including:

Woods Hole Oceanographic Institute Science Journalism Fellow, 2017

Made a Fellow of the Royal Geographical Society (with IBG) for continuing work documenting environmental issues in Asia (2014).

Environmental Film of the Year - Winner - 'The Toxic Price of Leather'. Atkins CIWEM Environmental Photographer of the Year Competition 2014.

Seven-time recipient of travel grant from The Pulitzer Center on Crisis Reporting (2009-2017).

Published 'Meltdown', a multimedia eBook documenting China's environmental crises in the early 21st Century (2013)

Photocrati Fund Honourable Mention (2013 & 2012).

First Place for Multimedia in the Press Photographer's Year Awards (2011).

Shortlisted at the Lumix Festival for Young Photojournalists in Multimedia Category (2010).

Honourable mention at the Earth Journalism Awards at COP15 (2009).

First recipient of the David Alan Harvey Fund for Emerging Photographers (2008).

Selected to undertake a 1-year paid internship at the photojournalism agency Magnum Photos (2004-2005). Mentored by the late, Philip Jones Griffiths.

I collaborate extensively with the Pulitzer Center on Crisis Reporting who have helped sponsor many of my projects in China. These projects have included a 4000km journey across the country documenting the threats from increasing desertification, a 7-province trip investigating the impacts of disappearing wetlands and a 1-month journey across the Tibetan plateau photographing the effects of climate change on the 'roof of the world'.

I am a senior lecturer on Bolton University's International Multimedia Journalism Programme in Beijing and am involved in education-outreach programmes both in Asia and the United States, using visual storytelling to communicate the issues that I cover to a wide variety of audiences. To date, I have presented my work and spoken to over 50 institutions including:

The Woodrow Wilson Center for Scholars

The Shanghai World Expo

The Climate Institute

American University

Georgetown University

State Department of the US Government

BBC World Service

# data[].attributes.attachment_link.title
About / Contact - Sean Gallagher - Photographer, Beijing, China

# data[].attributes.attachment_link.description
get in touch send me a message Connect with me About me My name is Sean Gallagher, a British photographer and filmmaker who has been based in Asia for over a decade. From the Tibetan Plateau to the Indonesian archipelago, I often spend months in the field travelling across the continent documenting its most important environmental, social and cultural issues for some of the world's leading news outlets.

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BEIJING (Reuters) - Beijing issued its first orange smog alert ahead of winter on Friday, forecasting heavy air pollution over the next four days, the second-highest alert in China's four-tier emergency response system.

Vehicles with National I and II emission standards and trucks transporting waste earth and construction debris will be banned from roads between Nov. 4 and Nov. 8, according to a notice posted on Weather.com - a website affiliated with China's National Meteorological Administration.

Large parts of northern China suffer from chronic smog during the bitterly cold winters because much of the heating demand is still met by coal. Pollution alerts during the winter pollution season are common in the region - a problem that the government has struggled to solve despite a multi-year effort.

Authorities in smog-blighted northern provinces such as Hebei, Henan, Shandong and Shanxi have urged their major industrial cities to slash steel output ahead of winter, part of the Ministry of Environmental Protection's smog battle plan to cut levels of hazardous airborne particles known as PM2.5 air pollutants by more than a quarter in the Beijing-Tianjin-Hebei area by 2017 from 2012 levels.

But measures taken so far have had little or no effect. PM2.5 concentration levels in the Beijing-Tianjin-Hebei area remained at around 52 micrograms in September, the same as last year.

China's Environment Minister Li Ganjie acknowledged last month the government's efforts to meet air quality targets for the year face "huge difficulties," and has asked for the public's patience.

Reporting by Lusha Zhang and Se Young Lee; Editing by Michael Perry

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monetary / fiscal policy / policy makers

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China's capital issues orange alert for upcoming smog

# data[].attributes.attachment_link.description
BEIJING (Reuters) - Beijing issued its first orange smog alert ahead of winter on Friday, forecasting heavy air pollution over the next four days, the second-highest alert in China's four-tier emergency response system. Vehicles with National I and II emission standards and trucks transporting waste earth and construction debris will be banned from roads between Nov.

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Smog is a very major conflict in China. It got so bad that when they have a celebration day, all of the factories are ordered to shut off so then people can see the blue sky. Smog is parts of ozone flying low to the ground and/ fog with acid mixed into it.

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Earlier this week, a thick layer of smog rolled into China's capital city, turning skyscrapers into shadows and clear air into a yellow fog. Caught on a time lapse by Chas Pope, the smog rolls in like a dust storm in a desert, billowing into the streets of Beijing.

Smog torpedoed air quality in Beijing and 24 other Chinese cities this week, leading authorities to declare a national red alert for 'severe fog'-the highest level of alerts.

This isn't the first time that smog has blanketed China. In recent years, poor air quality in Beijing has closed schools and caused farmers in the region to panic over the lack of sunlight. Protective face masks have become a common day-to-day sight, and grim poems salute the smog from cancer's point of view, even as Mark Zuckerberg-seemingly oblivious-went for a run in the yellow haze last year.

Why does smog keep blanketing Beijing? Smog in China has many causes, including pollution from industries and traffic, but it tends to happen more often in the winter, when plummeting temperatures cause electricity demand to soar. This pollution can come from many sources, but burning coal has been linked to the largest number of air pollution deaths in China, causing 366,000 premature deaths in 2013.

In the winter, more families are turning on their heaters-and most of the energy used to run them comes from coal-fired power plants that send tiny particles of charred dust into the air.

Those tiny particles, or particulate matter, are what turns clean air into smog. Particles in the air can reduce visibility and contribute to acid rain, which can damage vegetation. The particles can also discolor buildings, but the primary concern with particulate matter is what it can do to the human body. Particles smaller than 10 micrometers are of particular concern to health experts, as particles that small can damage the lungs, aggravate asthma, and even cause heart attacks. Inhaling particulate matter can even prove fatal for people who have existing heart or lung conditions.

Beijing's smog woes are compounded by an accident of geography, according to AccuWeather. Beijing is bordered by the Xishan and Yanshan mountains. When a high pressure weather system moves in, air near the city's surface doesn't move up and over the nearby mountain ranges. It just sits there, getting more and more polluted, and residents keep breathing it in.

China is taking steps to address the issue. The government has restricted driving in an effort to staunch air pollution from cars. But that measure is temporary. Chinese officials announced this week that the country would spend $360 billion on renewable energy projects, amping up its reliance on solar and wind. But it has a long way to go. China is still the world's largest consumer of coal by far, and plans to continue using the sooty source of power.

There is some cause for optimism. Like Beijing, Los Angeles also sits in a bowl-like depression, hemmed in by hills and sea-and like Beijing, it once had a serious smog problem. But strict regulations implemented over the past few decades have helped reduce the amount of smog in Los Angeles, bringing back blue skies. There's hope that they could return to China too, though residents shouldn't expect to breathe easy any time soon.

# data[].attributes.attachment_link.description
Earlier this week, a thick layer of smog rolled into China's capital city, turning skyscrapers into shadows and clear air into a yellow fog. Caught on a time lapse by Chas Pope, the smog rolls in like a dust storm in a desert, billowing into the streets of Beijing.

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His audience has been from the National Geographic News, the BBC, the Wall Street Journal and the Guardian to Schools like LCA

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As 2016 gave way to 2017, residents of Beijing, Tianjin, and many other northern Chinese cities suffered through the longest stretch of stifling air pollution ever recorded in the country. They choked through eight continuous days of thick, light-blocking haze, starting Dec. 30, 2016. This stretch of bad air began only a week after people in 70 northern Chinese cities were enveloped by similar days of haze composed of high concentrations of particles less than 2.5 μm in diameter (PM2.5).

Also known as ultrafine particulates, PM2.5 consists of solids and liquids. Its sources include black carbon from incomplete combustion as well as sulfates and nitrates. Levels of such ultrafine particles surpassed 500 μg per cubic meter of air in both of the recent incidents in China.

That level is twice the daily concentration of 250 µg/m³ that the U.S. Environmental Protection Agency considers hazardous to human health. In contrast, few U.S. cities recorded an air quality index of above 50, which can be translated to a PM2.5 concentration of 12 µg/m³, during the recent days that northern China's air was filled with haze, according to EPA data.

The recent bouts of toxic smog sent tens of thousands of residents fleeing Beijing and other northern Chinese cities for cleaner air abroad or in southern China. Angry protests and bitter jokes flooded WeChat and Weibo, China's most popular social media. The complaints about the government's failure to deal with dangerous air pollution, however, fail to take into account the complicated haze situation and the largely unknown mechanisms that create the pollution.

Geography plays an important role in northern China's air pollution. The Beijing-Tianjin-Hebei region is surrounded by mountains which block diffusion of the haze. The pollution becomes worse during winters, said Yuesi Wang, a leading scientist at the Beijing-based Institute of Atmospheric Physics (IAP), which is part of the Chinese Academy of Sciences (CAS). Speaking at a forum held in November 2016 in Beijing, Wang explained that weather factors-such as high humidity and situations when warmer air aloft holds colder air at the surface-intensify haze formation. In winter, slower air flow and stable atmospheric outer layers-which inhibit smog diffusion-plus the burning of coal for indoor heat result in much more hazy days than in other seasons.

Although China has suffered serious air pollution for decades, attention to air pollution in northern China initially was focused on sulfates and nitrogen oxides as well as larger particulate matter called PM10. The latter consists of particulates less than 10 μm in diameter, primarily wind-carried dust from construction sites and sand storms.

Only recently has attention centered on PM2.5, which accounts for 70% of PM10 and can combine with vapor in the air to form what is called smog or haze. China started regularly measuring PM2.5 in 2012 and began releasing data on it in 2013.

Those data suggest that emissions of fine particulates are the biggest source of northern China's haze. A report on the 2015 state of the environment issued by the Chinese Ministry of Environmental Protection last year indicates that air quality in 265 of the 338 major Chinese cities exceeded the national health standard that year.

Coal burning for heat, cooking, and electricity generation, vehicle emissions and airborne dusts are widely considered the main sources of both PM2.5 and other pollutants. According to Wang, the majority of PM2.5 comes from complicated photochemical reactions between numerous sulfates, nitrogen oxides, and other inorganic and organic chemicals.

Polluting particulates smaller than 2.5 μm can enter human cells and cause serious health hazards. For example, such tiny particles can have significant negative respiratory effects. A 2016 study also found that for every 5 µg/m³higher concentration of PM2.5, there was a 20% increase in the rate of coronary artery calcium deposits, leading to a higher risk of coronary diseases ( Lancet, 2016, DOI: 10.1016/s0140-6736(16)31597-5). Another study found that for every 5 µg/m³ higher concentration of PM2.5, the risk of hypertension increased by 22% in people living in the most polluted areas ( Eur. Heart J., DOI: 10.1093/eurheartj/ehw413).

Although the data in these studies are not specific to China, a study on the global burden of disease found that outdoor air pollution contributed to 1.2 million premature deaths in China each year, making it the fourth leading risk factor for deaths after dietary risks, high blood pressure, and smoking. That study was carried out by the Institute for Health Metrics and Evaluation at the University of Washington and released by the World Health Organization in 2013.

Northern China's current haze problem stems from recent changes in the region: the accelerated development of heavy industries, the surge in coal burning associated with them, and increased car ownership.

"The coal consumption per kilometer in the Beijing-Tianjin-Hebei region is 30 times the world's average, which is the primary driving factor of PM2.5 and haze," said Xiangwan Du, deputy director of China's National Advisory Committee for Energy Policy. In 2015, the region consumed 400 million metric tons of coal, according to a book published last year by the China Energy Research Society.

A 2013 national action plan strengthened existing policies requiring control of two major types of air pollution-sulfur oxides and nitrogen oxides-from power plants and other heavy users of coal. But these efforts are not enough to curb the emission and formation of PM2.5, said Xinmin Zhang of the Chinese Research Academy of Environmental Sciences (CRAES).

"To fight the serious haze, overall coal consumption and pollutant emission must be dramatically reduced," Fuqiang Yang, a senior adviser to Natural Resources Defense Council (NRDC), a U.S.-based environmental group, told C&EN.

In response to the situation, the Beijing municipal government has imposed a strict car-control policy-it uses lottery draws to control new car ownership and limits how many cars are on the road on any given day-and banned coal burning in its urban areas since 2012. Yet the heavy coal consumption in neighboring Hebei province easily overshadows the effects of Beijing's policy as air pollution drifts across the region.

Facing strong public pressure, China's government began to implement its Action Plan on Prevention & Control of Air Pollution in 2013. In the plan, the government pledged to slash coal consumption from around 67% of the nation's total energy use in 2012 to 65% by 2017. It also vowed to reduce PM2.5 levels by 15-25% by 2020. Under this policy, thousands of polluting factories were shut down, particularly in north China.

Despite these strict national policies on air pollution control, northern China's haze hasn't fully lifted. According to Report of the State of the Environment in China 2015, the 74 Chinese cities tracked in accordance with the action plan, which include all provincial capitals and other large cities, the average PM2.5 concentration in 2015 was 55 µg/m³, a 14.1% reduction from 2014. In the Beijing-Tianjin-Hebei region, the average annual level of PM2.5 was 77 μg/m ³ in 2015, down from 106 µg/m³ in 2013. In 2015, Beijing recorded 42 days of the highest polluting days (defined as those with a PM2.5 concentration of more than 500 µg/m³), three days fewer than 2014.

To demonstrate to the world its capacity to deal with air pollution, China adopted emergency air pollution control measures before and during the weeklong November 2014 Asia-Pacific Economic Cooperation (APEC) summit held in Beijing. Thousands of industrial plants were temporarily closed even though they met emission standards. Average concentrations of PM2.5 fell to 37 µg/m³ during the meeting and long-blocked blue sky reappeared in Beijing. However, brown haze chased away the blue after the summit when the plants restarted.

Because of their shutdowns for APEC, industries in Beijing, Tianjin, and Hebei province had losses of 3.5 billion yuan ($500 million), said Zhang of CRAES. The central and local governments reimbursed companies and rural residents who were banned from burning coal during the APEC meeting for most of their financial losses.

Zhang said that to permanently improve air quality in Beijing, more plants in Hebei province have to be closed. But, she admitted, this would entail huge costs and the loss of many jobs. "Local governments in Hebei province cannot afford the cost, yet the much richer Beijing municipal government refused to offer enough compensation to Hebei."

Although the overall efforts to curb pollution are escalating, many facilities have tried to cut costs and evade strict emission limits by covertly shutting down their air pollution controls, often at night. There are no accurate estimates of how much these illicit emissions contributed to long-term pollution and the corresponding haze. However, websites of environmental regulation agencies at different levels of government indicate that virtually every pollution inspection by regulators in recent years detected dozens of such illegal emissions.

Climate change also factors into the formation of haze. "With global warming, the temperature difference across the north hemisphere is dramatically reduced, resulting in less wind, particularly in winter," said Linsheng Yang, a senior scientist at Institute of Geographic Sciences and Natural Resources Research under CAS. He told C&EN that global warming may help explain why residents continue to report serious haze despite the decrease in pollutant concentrations.

NRDC's Yang suggested the government tackle haze and climate change together. "Reducing carbon emission can reduce PM2.5 concentration at the same time," he said. Yet he worries that economic stimulus policies aimed at improving the slowed-down Chinese economy-such as looser monetary policies, heavy investment in infrastructure, and growth in construction, which boosts steel and cement production-could raise energy consumption in the second half of 2017.

"Perhaps this explains why after a recordable reduction of PM2.5 concentration in [the past] three years, residents in northern Chinese cities experienced increased haze this winter," he told C&EN.

Yang also appealed for more regional coordination to fight haze. "While the public and policy attention are focused in Beijing-Tianjin-Hebei region, the coal consumption in other neighboring provinces such as Shandong is increasing and may offset Hebei's effort to slash the production capacity of heavy industry." Located to Beijing's southeast, Shandong province is home to one of the biggest concentrations of chemical manufacturing in China.

The policy limiting cars in Beijing might also be backfiring. Jing Tian, cofounder of the Beijing-based organization Clear Air Defense, told a seminar in December 2016 that the reduced emissions from cars in Beijing could be offset by the 100,000 diesel-engine trucks in use in the city's outskirts. A diesel truck with a nonworking emission controls can contribute tens of times the pollutants of an average car.

Although diesel trucks might be a bigger culprit for forming haze, the 5.7 million vehicles in Beijing remains a primary contributor of PM2.5 in the capital city, said Yan Ding of MEP. Those vehicles contributed 31% of the city's fine particulates in 2015, according to Beijing's Environmental Statement for 2015,

But not everyone is convinced that vehicles in Beijing are the primary cause. In 2013, a team headed by Renjian Zhang at IAP published a study claiming vehicle emissions contributed only 4% of the identifiable sources of PM2.5 in Beijing, ( Atmos. Chem. Phys., DOI: 10.5194/acp-13-7053-2013). This estimate differs significantly from the official figure of 31%. The study by Zhang's team led to a huge public protest against car control policy in Beijing in late 2013. The Beijing municipal government and CAS scientists rejected the study's result.

Despite the official rejection of the study, "it highlights the great uncertainty of source attribution of PM2.5," said an atmospheric scientist based in Guangzhou who asked not to be identified because of fear of political repercussions.

A newly published follow-up study by IAP's Zhang and colleagues further confirmed the uncertainty in attributing the source of PM2.5. According to the study, using different models, researchers found that the contribution of the primary sources of pollutants-including industrial pollution, soil dust, biomass burning, traffic emissions, and coal burning-changed dramatically. How much each contributed varied widely in the models ( Sci. Tot. Environ., 2015, DOI: 10.1016/j.scitotenv.2015.11.057).

Though uncertainties remain in the source of PM2.5, other atmospheric chemistry studies have shed light on the mechanism of serious haze formation. Researchers have found an unexpectedly high level of sulfates, which are a major component of PM2.5, in China. Formation of sulfates was thought to rely on a photochemical reaction. That means northern China's sun-blocking haze should have dramatically reduced the available light for the necessary reaction.

A team headed by Kebin He of Tsinghua University and their German colleagues found that instead of relying on photochemistry, the sulfates were rapidly formed by oxidization of SO ₂ by NO 2 in an environment with a high level of aerosolized water. In a recent paper, the team concluded that northern China's haze amplifies itself and that cutting NO ₂ emissions is important to reduce the formation of sulfates ( Sci. Adv., 2016, DOI: 10.1126/sciadv.1601530).

Another international team, led by Gehui Wang of CAS' Institute of Earth Environment and Renyi Zhang of Texas A&M University, found that nitrogen dioxide converts sulfur dioxide to sulfates via an aqueous oxidation mechanism. Their study showed that this transformation, which they suggest played a role in 1952's historic London Fog as well as in contemporary Chinese haze events, occurs efficiently only on nonacidic particles ( Proc. Nat. Acad. Sci., 2016, DOI: 10.1073/pnas.1616540113).

The conditions that led to these events differed, however. The 1952 event, which happened at a time when widespread coal burning in London polluted its air with SO ₂, started on cloud droplets. "But northern China's haze starts from much smaller nanoparticles, and the sulfate formation process is only possible with ammonia to neutralize the particles," Zhang told C&EN. "Our results suggest that controlling NO ₂ and NH ₃ emissions is likely effective to reduce severe haze in China, in addition to controlling SO ₂."

Seeking to better understand the strengthening of northern China's haze even as pollution controls tightened, Min Hu of Peking University, Renyi Zhang of Texas A&M, and their teams took a look at black carbon, which is a pollutant that contributes both to haze and global warming and is a major component of PM2.5. They studied how black carbon's morphology can change from its newly emitted fractal form into compact particles with greatly enhanced light-absorbing characteristics.

They found the morphology modification of black carbon took just 4 to 6 hours in Beijing-four times as quickly as in Houston, which has cleaner air. Beijing's rapid-aging black carbon particles with their enhanced light absorption could contribute to stabilization of the atmosphere, leading to formation of more severe haze events.

"Our studies indicate that already polluted urban environments and polluting particulates could interact to cause a multiplication of the haze effect. To tackle Beijing's haze, researchers should not only study primary pollutants but their complicated interaction with atmosphere," Zhang told C&EN.

Ozone is the primary air pollutant in Houston, which was used as a comparison in the Peking-Texas A&M study.

Although the clean air effort in Beijing currently is focused on PM2.5, ozone pollution is increasing in Beijing and some other Chinese cities because of the increased emission of nitrogen oxides and volatile organic compounds (VOCs) mainly from vehicles in recent years, said Wang of IAP.

Shiqiu Zhang, a professor of environmental governance at Peking, points out that the government does not require control of VOC emissions. "When dealing with PM2.5, policymakers and researchers should coordinate their efforts to fight other pollutants to avoid unexpected environmental effects," she told C&EN.
CORRECTION: This story was updated on Feb. 13, 2017, to correct the unit of the measurement PM2.5 in the graphic, which was incorrectly stated as mg per m3 of air. The unit is μg per m3 of air. The story also incorrectly made a reference to an air pollutant as carbon black. The pollutant is black carbon.

# data[].attributes.attachment_link.authors[].name
Hepeng Jia and Ling Wang, special to C&EN

# data[].attributes.attachment_link.title
Peering into China's thick haze of air pollution

# data[].attributes.attachment_link.description
As 2016 gave way to 2017, residents of Beijing, Tianjin, and many other northern Chinese cities suffered through the longest stretch of stifling air pollution ever recorded in the country. They choked through eight continuous days of thick, light-blocking haze, starting Dec. 30, 2016.

# data[].attributes.body
He is a photographer who wants to spread the word of China's pollution issue.

# data[].attributes.attachment_link.provider_name
Sean Gallagher - Photographer, Beijing, China

# data[].attributes.attachment_link.readable_text
get in touch

send me a message

Connect with me

About me

My name is Sean Gallagher, a British photographer and filmmaker who has been based in Asia for over a decade.

From the Tibetan Plateau to the Indonesian archipelago, I often spend months in the field travelling across the continent documenting its most important environmental, social and cultural issues for some of the world's leading news outlets.

I am a 7-time recipient of the Pulitzer Center on Crisis Reporting travel grant, am represented by National Geographic Creative and am a Fellow of the Royal Geographical Society (with IBG).

I graduated in Zoology from university in the United Kingdom and it is my background in science that has led to much of my work being focused on communicating environmental issues through visual storytelling.

I do this by creating photographic, video and multimedia projects that highlight individual's stories from communities that are affected by issues such as desertification, deforestation, pollution, species extinction and climate change.

My distinctive approach to visual storytelling and extensive experience in Asia, allows me to create unique photography and video projects for my editorial and commercial clients.

My work has appeared with editorial outlets including The New York Times, National Geographic News, CNN, The Atlantic and BBC News.

I have received a number of awards and grants for my work, including:

Woods Hole Oceanographic Institute Science Journalism Fellow, 2017

Made a Fellow of the Royal Geographical Society (with IBG) for continuing work documenting environmental issues in Asia (2014).

Environmental Film of the Year - Winner - 'The Toxic Price of Leather'. Atkins CIWEM Environmental Photographer of the Year Competition 2014.

Seven-time recipient of travel grant from The Pulitzer Center on Crisis Reporting (2009-2017).

Published 'Meltdown', a multimedia eBook documenting China's environmental crises in the early 21st Century (2013)

Photocrati Fund Honourable Mention (2013 & 2012).

First Place for Multimedia in the Press Photographer's Year Awards (2011).

Shortlisted at the Lumix Festival for Young Photojournalists in Multimedia Category (2010).

Honourable mention at the Earth Journalism Awards at COP15 (2009).

First recipient of the David Alan Harvey Fund for Emerging Photographers (2008).

Selected to undertake a 1-year paid internship at the photojournalism agency Magnum Photos (2004-2005). Mentored by the late, Philip Jones Griffiths.

I collaborate extensively with the Pulitzer Center on Crisis Reporting who have helped sponsor many of my projects in China. These projects have included a 4000km journey across the country documenting the threats from increasing desertification, a 7-province trip investigating the impacts of disappearing wetlands and a 1-month journey across the Tibetan plateau photographing the effects of climate change on the 'roof of the world'.

I am a senior lecturer on Bolton University's International Multimedia Journalism Programme in Beijing and am involved in education-outreach programmes both in Asia and the United States, using visual storytelling to communicate the issues that I cover to a wide variety of audiences. To date, I have presented my work and spoken to over 50 institutions including:

The Woodrow Wilson Center for Scholars

The Shanghai World Expo

The Climate Institute

American University

Georgetown University

State Department of the US Government

BBC World Service

# data[].attributes.attachment_link.title
About / Contact - Sean Gallagher - Photographer, Beijing, China

# data[].attributes.attachment_link.description
get in touch send me a message Connect with me About me My name is Sean Gallagher, a British photographer and filmmaker who has been based in Asia for over a decade. From the Tibetan Plateau to the Indonesian archipelago, I often spend months in the field travelling across the continent documenting its most important environmental, social and cultural issues for some of the world's leading news outlets.

# data[].attributes.body
Sean Gallagher is a British Photographer and film maker who has been based in Asia for over a decade.