Bicycle riders wearing masks wait during heavy traffic on a smoggy day in Beijing, China, 04 January 2017. China issued its first-ever national red alert for severe fog on 04 Jan 2017, after 24 of its cities across the country have already issued red alerts for air pollution problems. Red is the highest level in the country's four-tier warning system. (Photo by How Hwee Young/EPA)





In this photo taken Friday, December 30, 2016, a Chinese man walks past ceramic plates with images of Chinese President Xi Jinping displayed at a rest stop near Beijing. During his annual New Year Eve's speech, Chinese President Xi Jinping says his government will continue to focus on poverty alleviation at home and resolutely defending China's territorial rights on the foreign front. (Photo by Ng Han Guan/AP Photo)





People tour between structures built of ice in the Ice and Snow World, December 31, 2016, in China, Harbin. (Photo by Feature China/Barcroft Images)





Robot waiters are seen working at a robot restaurant in Kunshan, China on May 22, 2016. The restaurant has a total of 10 robots in heights of 1.2 meters. Each robot costs 50,000 yuan and all used for delivery and cooking. (Photo by Zhong Zhenbin/Anadolu Agency/Getty Images)





Chinese women walk out from a local market in Beijing, China, Sunday, January 8, 2017. Residents enjoyed the reprieve after a weeklong smog alert as clean air returned to the Chinese capital. (Photo by Ng Han Guan/AP Photo)





People wear masks on a hazy day in Beijing, China, December 31, 2016. (Photo by Thomas Peter/Reuters)





Workers build wooden scaffolding at a construction site in Beijing, China, December 31, 2016. (Photo by Thomas Peter/Reuters)





A guard keeps watch at a construction site in Beijing, China, December 31, 2016. (Photo by Thomas Peter/Reuters)





A worker rides a bicycle outside a construction site in Beijing, China, December 31, 2016. (Photo by Thomas Peter/Reuters)





A woman wears a mask as she rides near the Bund during a polluted day in Shanghai, China, January 2, 2017. (Photo by Aly Song/Reuters)





A man practices Tai Chi in a park on a sunny winter day in Beijing, China, January 2, 2017. (Photo by Thomas Peter/Reuters)





People wearing masks dance at a square among heavy smog during a polluted day in Fuyang, Anhui province, China, January 3, 2017. (Photo by Reuters/China Daily)





A woman walks past a bridge among heavy smog during a polluted day in Fuyang, Anhui province, China, January 3, 2017. (Photo by Reuters/China Daily)





Investors look at computer screens showing stock information on the first trading day after the New Year holiday at a brokerage house in Shanghai, China, January 3, 2017. (Photo by Aly Song/Reuters)





An investor walks in front of an electronic board showing stock information on the first trading day after the New Year holiday at a brokerage house in Shanghai, China, January 3, 2017. (Photo by Aly Song/Reuters)





A security guard wears a face mask in Beijing, China, January 3, 2017. (Photo by Thomas Peter/Reuters)





People exercise among heavy smog in Hefei, Anhui province, China, January 3, 2017. (Photo by Reuters/Stringer)





A view of sunset is seen in smog in Zhengzhou, Henan province, China January 2, 2017. (Photo by Reuters/Stringer)





A police officer wears a face mask on a polluted day in Beijing, China, January 3, 2017. (Photo by Thomas Peter/Reuters)





A woman wears a face mask on a polluted day in Beijing, China, January 3, 2017. (Photo by Thomas Peter/Reuters)





People wear face masks as they cross a street on a polluted day in Beijing, China January 4, 2017. (Photo by Thomas Peter/Reuters)





People wear face masks as they cross a street on a polluted day in Beijing, China January 4, 2017. (Photo by Thomas Peter/Reuters)





People wear face masks as they cross a street on a polluted day in Beijing, China January 4, 2017. (Photo by Thomas Peter/Reuters)





People wear face masks on a polluted day in Beijing, China January 4, 2017. (Photo by Thomas Peter/Reuters)





People wear face masks as they cross a street on a polluted day in Beijing, China January 4, 2017. (Photo by Thomas Peter/Reuters)





People wear face masks as they cross a street on a polluted day in Beijing, China January 4, 2017. (Photo by Thomas Peter/Reuters)





A couple wears masks on a street amid heavy smog in downtown Shanghai, China January 4, 2017. (Photo by Aly Song/Reuters)





A woman wears a face mask as she walks on a street on a polluted day in Beijing, China, January 4, 2017. (Photo by Thomas Peter/Reuters)





A woman wears a face mask as she walks on a street on a polluted day in Beijing, China, January 4, 2017. (Photo by Thomas Peter/Reuters)





A woman wears a face mask as she walks on a street on a polluted day in Beijing, China, January 4, 2017. (Photo by Thomas Peter/Reuters)





A waitress pours liquor into ice cups on an ice counter during a photo opportunity at the Ice Palace in Shangri-La Hotel in the northern city of Harbin, Heilongjiang province January 6, 2014. (Photo by Kim Kyung-Hoon/Reuters)





Smog is seen over the city during haze weather in Tianjin, China, January 3, 2017. Picture taken January 3, 2017. (Photo by Reuters/Stringer)





People sort old newspapers and books for recycling in a street in Beijing, China January 5, 2017. (Photo by Thomas Peter/Reuters)





Masks are pictured on sculptures in a park during a hazy day in Puyang, Henan province, China January 4, 2017. (Photo by Reuters/Stringer)





Contestants ski past a snow replica of the Qinian Hall of the Temple of Heaven during a competition in Changchun, Jilin province, January 4, 2017. (Photo by Reuters/Stringer)





People dance to exercise in a park during a haze day in Beijing, China, January 4, 2017. (Photo by Reuters/Stringer)





People hang lanterns at Houhai lake during a polluted day in Beijing, China, January 5, 2017. (Photo by Reuters/Stringer)





Couples attend a mass wedding on the second day of Harbin's International Ice Festival, in Harbin, Heilongjiang province, China, January 6, 2017. (Photo by Reuters/Stringer)





Couples pose for pictures during a mass wedding on the second day of Harbin's International Ice Festival, in Harbin, Heilongjiang province, China, January 6, 2017. (Photo by Reuters/Stringer)





Skaters perform during a mass wedding on the second day of Harbin's International Ice Festival, in Harbin, Heilongjiang province, China, January 6, 2017. (Photo by Reuters/Stringer)





A man swims in the partially frozen Houhai lake in Beijing, China January 6, 2017. (Photo by Thomas Peter/Reuters)





A group of fans dressed in homemade replica armour of “Avengers: Age of Ultron” movie characters, Iron Man, Captain America and Thor, watch the film in a theatre in Changchun, Jilin province, China on May 16, 2015. (Photo by Reuters/Stringer)





A woman walks past parked cars in heavy smog in Urumqi, Xinjiang Uighur Autonomous Region, China January 7, 2017. (Photo by Reuters/Stringer)





A visitor is seen in front of inflatable chicken that local media say bears resemblance to U.S. President-elect Donald Trump shown at a factory ahead of the Year of the Rooster in Jiaxing, Zhejiang province, China January 12, 2017. (Photo by Aly Son/Reuters)





A woman walks past an advertisement at the entrance of a clothing store in Beijing on January 13, 2017. Chinese exports fell more than expected in December, data showed on January 13, deepening concerns about the trade outlook for the world's number-two economy as Donald Trump prepares to take office. (Photo by Wang Zhao/AFP Photo)





A man has a meal at Shigezhuang village, where many migrant workers living there have left for their hometowns ahead of the Chinese Lunar New Year, in Beijing, China, January 13, 2017. (Photo by Jason Lee/Reuters)





A woman is seen at Shigezhuang village, where many migrant workers living there have left for their hometowns ahead of the Chinese Lunar New Year, in Beijing, China, January 13, 2017. (Photo by Jason Lee/Reuters)





A woman walks up the steps decorated ahead of the Chinese New Year festival in Beijing, China, Thursday, January 12, 2017. The Chinese Lunar New Year is the most important holiday for Chinese and hundreds of millions are expected to return to their hometown to spend the new year with their family and relatives. (Photo by Ng Han Guan/AP Photo)





Two women carrying a child walk along a railway in Beijing on January 12, 2017. (Photo by Wang Zhao/AFP Photo)





An aerial view shows people touring between the large-scale ice sculptures at the 18th Harbin Ice and Snow World during its trial run opening to public in Harbin city, Heilongjiang province, China, 21 December 2016. Some 180,000 cubic meters of ice and 150,000 cubic meters of snow were used to build the 800,000-square-meter ice wonderland. The 33rd Harbin International Ice and Snow Festival will kick off on 05 January 2017 that will last about three months. (Photo by Tian Weitao/EPA)





A woman holds her mask for protection against air pollution on a pedestrian overhead bridge in Beijing as the capital of China is shrouded by heavy smog on Tuesday, December 20, 2016. Thick, gray smog fell over Beijing on Tuesday, clouding China's capital in a haze that spurred authorities to cancel flights and close some highways in emergency measures to cut down on air pollution. (Photo by Andy Wong/AP Photo)





A woman wearing a mask for protection against air pollution walks on a pedestrian overhead bridge in Beijing as the capital of China is shrouded by heavy smog Monday, December 19, 2016. Engulfed in choking smog, some northern Chinese cities limited the number of cars on roads and temporarily shut down factories on Monday to cut down pollution during a national “red alert”. More than 700 companies stopped production in Beijing and traffic police were restricting drivers by monitoring their license plate numbers, state media reported. (Photo by Andy Wong/AP Photo)





Chinese worshippers wearing masks burn incense while offering prayer at Beijing's Yonghegong Lama Temple as the Chinese capital is blanketed by heavy smog on the first day of the New Year, Sunday, January 1, 2017. (Photo by Andy Wong/AP Photo)