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Open Image ModalA man pushes a bike onto a bridge during a day of heavy pollution in Harbin in northeast China's Heilongjiang province Monday Oct. 21, 2013. Visibility shrank to less than half a football field and small-particle pollution soared to a record 40 times higher than an international safety standard in the northern Chinese city as the region entered its high-smog season. (AP Photo) CHINA OUT (credit:AP)
CHINA-ENVIRONMENT-POLLUTION(02 of64)
Open Image ModalBuildings and streets are seen under heavy smog in Harbin, northeast China's Heilongjiang province on October 22, 2013. Thick smog enveloped a major Chinese city for a third day on October 22, with schools and a regional airport shut and poor visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
Heavy Smog Continues To Disrupt Northeast China(03 of64)
Open Image ModalHARBIN, CHINA - OCTOBER 21: (CHINA OUT) Pedestrians wearing masks walk along a road as heavy smog engulfs the city on October 21, 2013 in Harbin, China. Expressways, schools and an airport remain closed as heavy smog continues to disrupt northeast China. (Photo by ChinaFotoPress/Getty Images) (credit:Getty Images)
Heavy Smog Continues To Disrupt Northeast China(04 of64)
Open Image ModalCHANGCHUN, CHINA - OCTOBER 21: (CHINA OUT) A man wearing mask walks along a road as heavy smog engulfs the city on October 21, 2013 in Changchun, China. Expressways, schools and an airport remain closed as heavy smog continues to disrupt northeast China. (Photo by ChinaFotoPress/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(05 of64)
Open Image ModalBuildings and streets are seen under heavy smog in Harbin, northeast China's Heilongjiang province on October 22, 2013. Thick smog enveloped a major Chinese city for a third day on October 22, with schools and a regional airport shut and poor visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
Heavy Smog Continues To Disrupt Northeast China(06 of64)
Open Image ModalCHANGCHUN, CHINA - OCTOBER 21: (CHINA OUT) A woman wearing mask walks along a road as heavy smog engulfs the city on October 21, 2013 in Changchun, China. Expressways, schools and an airport remain closed as heavy smog continues to disrupt northeast China. (Photo by ChinaFotoPress/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(07 of64)
Open Image ModalStreets are seen under heavy smog in Harbin, northeast China's Heilongjiang province on October 22, 2013. Thick smog enveloped a major Chinese city for a third day on October 22, with schools and a regional airport shut and poor visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(08 of64)
Open Image ModalBuildings are seen under heavy smog in Harbin, northeast China's Heilongjiang province on October 22, 2013. Thick smog enveloped a major Chinese city for a third day on October 22, with schools and a regional airport shut and poor visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
Heavy Smog Continues To Disrupt Northeast China(09 of64)
Open Image ModalCHANGCHUN, CHINA - OCTOBER 21: (CHINA OUT) A woman and her son wearing masks walk along a road as heavy smog engulfs the city on October 21, 2013 in Changchun, China. Expressways, schools and an airport remain closed as heavy smog continues to disrupt northeast China. (Photo by ChinaFotoPress/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(10 of64)
Open Image ModalTraffic police are seen at a toll booth on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(11 of64)
Open Image ModalTraffic police are seen at a toll booth on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(12 of64)
Open Image ModalBuildings and streets are seen under heavy smog in Harbin, northeast China's Heilongjiang province on October 22, 2013. Thick smog enveloped a major Chinese city for a third day on October 22, with schools and a regional airport shut and poor visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
Heavy Smog Continues To Disrupt Northeast China(13 of64)
Open Image ModalHARBIN, CHINA - OCTOBER 22: (CHINA OUT) Pedestrians wearing masks walk along a road as heavy smog engulfs the city on October 22, 2013 in Harbin, China. Expressways, schools and an airport remain closed as heavy smog continues to disrupt northeast China. (Photo by ChinaFotoPress/Getty Images) (credit:Getty Images)
Heavy Smog Continues To Disrupt Northeast China(14 of64)
Open Image ModalJILIN, CHINA - OCTOBER 21: (CHINA OUT) Vehicles are driven along a bridge on the Songhua River as heavy smog engulfs the city on October 21, 2013 in Jilin, China. Expressways, schools and an airport remain closed as heavy smog continues to disrupt northeast China. (Photo by ChinaFotoPress/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(15 of64)
Open Image ModalStreets are seen under heavy smog in Harbin, northeast China's Heilongjiang province on October 22, 2013. Thick smog enveloped a major Chinese city for a third day on October 22, with schools and a regional airport shut and poor visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(16 of64)
Open Image ModalBuildings are seen under heavy smog in Harbin, northeast China's Heilongjiang province on October 22, 2013. Thick smog enveloped a major Chinese city for a third day on October 22, with schools and a regional airport shut and poor visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(17 of64)
Open Image ModalThis combination of photos shows streets under heavy smog in Harbin, northeast China's Heilongjiang province, on October 22, 2013 (top) and in the same place on August 27 (bottom). Thick smog enveloped a major Chinese city for a third day on October 22, with schools and a regional airport shut and poor visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(18 of64)
Open Image ModalA bus is seen at a toll booth on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(19 of64)
Open Image ModalA toll booth is shuttered as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(20 of64)
Open Image ModalA toll booth is shuttered as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(21 of64)
Open Image ModalA toll booth is shuttered as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(22 of64)
Open Image ModalA truck is seen waiting outside a toll booth after it is shuttered as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(23 of64)
Open Image ModalA truck is seen waiting outside a toll booth after it is shuttered as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(24 of64)
Open Image ModalA toll booth is shut down as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(25 of64)
Open Image ModalPasserbys cycle past a truck waiting outside a closed toll booth as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(26 of64)
Open Image ModalA truck is seen waiting outside a toll booth after it is shuttered as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(27 of64)
Open Image ModalResidents walk on a street through heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(28 of64)
Open Image ModalA woman walks with her child on a street as schools were closed due to the heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(29 of64)
Open Image ModalA woman walks with her child on a street as schools were closed due to the heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION(30 of64)
Open Image ModalA woman walks with her child on a street as schools were closed due to the heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(31 of64)
Open Image ModalA truck is seen waiting outside a toll booth after it is shuttered as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(32 of64)
Open Image ModalA toll booth is shuttered as heavy smog spreads on a highway as vehicles are forced to wait due to heavy smog in Jilin, northeast China's Jilin province on October 22, 2013. Thick smog enveloped China's northeast area for a third day on October 22, with schools and regional airports shuttered and low visibility forcing ground transport to a halt in places. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
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Open Image ModalIn this photo taken on June 29, 2013, tourists look at the Forbidden City from the top of Jinshan hill on a hazy day in Beijing, China. Chinas tourism industry has grown at a fast pace since the country began free market-style economic reforms three decades ago. However, it's latest tourism slogan "Beautiful China" has been derided as particularly inept at a time when record-busting smog has drawn attention to the environmental and health costs of Chinas unfettered industrialization. Some point to unsophisticated marketing as an explanation. (AP Photo/Alexander F. Yuan) (credit:AP)
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Open Image ModalIn this Wednesday, July 31, 2013 photo, a group of foreign tourists visit the Temple of Heaven in Beijing. Chinas tourism industry has grown at a fast pace since the country began free market-style economic reforms three decades ago. However, it's latest tourism slogan "Beautiful China" has been derided as particularly inept at a time when record-busting smog has drawn attention to the environmental and health costs of Chinas unfettered industrialization. Some point to unsophisticated marketing as an explanation. (AP Photo/Andy Wong) (credit:AP)
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Open Image ModalIn this Wednesday, Aug. 28, 2013 photo, a group of Italian tourists visit the Summer Palace with the Buddhist towers in the background in Beijing. Chinas tourism industry has grown at a fast pace since the country began free market-style economic reforms three decades ago. However, it's latest tourism slogan "Beautiful China" has been derided as particularly inept at a time when record-busting smog has drawn attention to the environmental and health costs of Chinas unfettered industrialization. Some point to unsophisticated marketing as an explanation. (AP Photo/Andy Wong) (credit:AP)
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Open Image ModalIn this photo taken on Sept. 13, 2013 tourists visit Tiananmen Square on a hazy day while an electronic screen shows a blue sky and white clouds as part of a propaganda video in Beijing, China. Chinas tourism industry has grown at a fast pace since the country began free market-style economic reforms three decades ago. However, it's latest tourism slogan "Beautiful China" has been derided as particularly inept at a time when record-busting smog has drawn attention to the environmental and health costs of Chinas unfettered industrialization. Some point to unsophisticated marketing as an explanation. (AP Photo/Alexander F. Yuan) (credit:AP)
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Open Image ModalIn this Wednesday, Aug. 28, 2013 photo, a tour guide and a tourist couple walk past a man taking a nap in a corridor of the Summer Palace in Beijing. Chinas tourism industry has grown at a fast pace since the country began free market-style economic reforms three decades ago. However, it's latest tourism slogan "Beautiful China" has been derided as particularly inept at a time when record-busting smog has drawn attention to the environmental and health costs of Chinas unfettered industrialization. Some point to unsophisticated marketing as an explanation. (AP Photo/Andy Wong) (credit:AP)
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Open Image ModalA motorcyclist wearing a mask and other cyclists ride past vehicles clogged with heavy traffic in Beijing Tuesday, Oct. 22, 2013. Beijing is seeking to tame its smog emergencies by preparing emergency measures, such as factory shutdowns and traffic limits, to kick in when air pollution levels are high. (AP Photo/Andy Wong) (credit:AP)
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Open Image ModalA woman wearing a face mask looks at the traffic as she bicycles on a road in Beijing Tuesday, Oct. 22, 2013. Beijing is seeking to tame its smog emergencies by preparing emergency measures such as factory shutdowns and traffic limits to kick in when air pollution levels are high. (AP Photo/Andy Wong) (credit:AP)
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Open Image ModalChinese women walk past buses and cars clogged with heavy traffic in Beijing Tuesday, Oct. 22, 2013. Beijing is seeking to tame its smog emergencies by preparing emergency measures, such as factory shutdowns and traffic limits, to kick in when air pollution levels are high. (AP Photo/Andy Wong) (credit:AP)
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Open Image ModalA woman wearing a face mask bicycles on a road in Beijing Tuesday, Oct. 22, 2013. Beijing is seeking to tame its smog emergencies by preparing emergency measures such as factory shutdowns and traffic limits to kick in when air pollution levels are high. (AP Photo/Andy Wong) (credit:AP)
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Open Image ModalA woman wears a mask during a day of pollution in Beijing Tuesday, Oct. 22, 2013. Beijing is seeking to tame its infamous smog by preparing emergency measures such as factory shutdowns and traffic limits to kick in when air pollution levels are especially heavy. (AP Photo/Ng Han Guan) (credit:AP)
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Open Image ModalA woman wears a mask as she waits to cross a road with her dogs during a day of pollution in Beijing Tuesday, Oct. 22, 2013. Beijing is seeking to tame its infamous smog by preparing emergency measures such as factory shutdowns and traffic limits to kick in when air pollution levels are especially heavy. (AP Photo/Ng Han Guan) (credit:AP)
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Open Image ModalA man pushes a bike onto a bridge during a day of heavy pollution in Harbin in northeast China's Heilongjiang province Monday Oct. 21, 2013. Visibility shrank to less than half a football field and small-particle pollution soared to a record 40 times higher than an international safety standard in the northern Chinese city as the region entered its high-smog season. (AP Photo) CHINA OUT (credit:AP)
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Open Image ModalChinese men walk on the street during a day of heavy pollution in Harbin in northeast China's Heilongjiang province Monday Oct. 21, 2013. Visibility shrank to less than half a football field and small-particle pollution soared to a record 40 times higher than an international safety standard in the northern Chinese city as the region entered its high-smog season. (AP Photo) CHINA OUT (credit:AP)
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Open Image ModalA Chinese woman wears a mask as she takes part in communal dancing during a day of heavy pollution in Harbin in northeast China's Heilongjiang province Monday Oct. 21, 2013. Visibility shrank to less than half a football field and small-particle pollution soared to a record 40 times higher than an international safety standard in the northern Chinese city as the region entered its high-smog season. (AP Photo) CHINA OUT (credit:AP)
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Open Image ModalA Chinese man covers his nose and mouth as he walks on the street during a day of heavy pollution in Harbin in northeast China's Heilongjiang province Monday Oct. 21, 2013. Visibility shrank to less than half a football field and small-particle pollution soared to a record 40 times higher than an international safety standard in the northern Chinese city as the region entered its high-smog season. (AP Photo) CHINA OUT (credit:AP)
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Open Image ModalA man pushes a bike onto a bridge during a day of heavy pollution in Harbin in northeast China's Heilongjiang province Monday Oct. 21, 2013. Visibility shrank to less than half a football field and small-particle pollution soared to a record 40 times higher than an international safety standard in the northern Chinese city as the region entered its high-smog season. (AP Photo) CHINA OUT (credit:AP)
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Open Image ModalTwo women cover up their mouths and noses with a jacket as they cross a street covered by dense smog in Harbin, northern China, Monday, Oct. 21, 2013. Visibility shrank to less than half a football field and small-particle pollution soared to a record 40 times higher than an international safety standard in one northern Chinese city as the region entered its high-smog season. (AP Photo/Kyodo News) JAPAN OUT, CREDIT MANDATORY (credit:AP)
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Open Image ModalA woman wearing a mask walk through a street covered by dense smog in Harbin, northern China, Monday, Oct. 21, 2013. Visibility shrank to less than half a football field and small-particle pollution soared to a record 40 times higher than an international safety standard in one northern Chinese city as the region entered its high-smog season. (AP Photo/Kyodo News) JAPAN OUT, CREDIT MANDATORY (credit:AP)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(51 of64)
Open Image ModalMotorists (C) and pedestrians (bottom R) commute during a period of heavy smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, a Chinese city famed for its annual ice festival on October 21, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(52 of64)
Open Image ModalBuildings are barely visible in heavy smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, a Chinese city famed for its annual ice festival on October 21, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(53 of64)
Open Image ModalA girl cycles on a street under heavy smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, which is famed for its annual ice festival, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(54 of64)
Open Image ModalA man wearing a mask walks in heavy smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, a Chinese city famed for its annual ice festival on October 21, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(55 of64)
Open Image ModalA woman wearing a face mask walks in heavy smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, a Chinese city famed for its annual ice festival on October 21, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(56 of64)
Open Image ModalA woman covers her mouth with her scarf in the smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, which is famed for its annual ice festival, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(57 of64)
Open Image ModalA woman wearing a mask covers her mouth with her hands as she walks in the smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, which is famed for its annual ice festival, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(58 of64)
Open Image ModalA woman walks in the smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, which is famed for its annual ice festival, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-ENVIRONMENT-POLLUTION-HEALTH(59 of64)
Open Image ModalLocal residents travel on a tricycle in the smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, which is famed for its annual ice festival, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-WEATHER-FOG(60 of64)
Open Image ModalThis picture taken on June 5, 2013 shows buildings under heavy smog in Beijing. The capital has seen 46 smog days among the 100 days from January 1 to April 10, a record over the last 60 years, the National Climate Center announced. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
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Open Image ModalThis picture taken on June 5, 2013 shows vehicles under heavy smog in Beijing. The capital has seen 46 smog days among the 100 days from January 1 to April 10, a record over the last 60 years, the National Climate Center announced. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-WEATHER-FOG(62 of64)
Open Image ModalThis picture taken on June 5, 2013 shows vehicles under heavy smog in Beijing. The capital has seen 46 smog days among the 100 days from January 1 to April 10, a record over the last 60 years, the National Climate Center announced. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-WEATHER-FOG(63 of64)
Open Image ModalThis picture taken on June 5, 2013 shows vehicles under heavy smog in Beijing. The capital has seen 46 smog days among the 100 days from January 1 to April 10, a record over the last 60 years, the National Climate Center announced. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)
CHINA-WEATHER-FOG(64 of64)
Open Image ModalThis picture taken on June 5, 2013 shows vehicles under heavy smog in Beijing. The capital has seen 46 smog days among the 100 days from January 1 to April 10, a record over the last 60 years, the National Climate Center announced on June 6. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images) (credit:Getty Images)