Editor's Note:
China's meteorological authorities issued or maintained yellow, orange, and red alerts for heavy air pollution covering 72 cities on January 2, 2016. The extent of the smog could be seen on one high-speed train, blackened by the pollution while making the 800-kilometer journey between Beijing and Shanghai. Photos: CFP
A high-speed train sits covered with dust on January 2, 2016, after completing the 800-kilometer trip between Beijing and Shanghai in just over five hours. 
A boy poses with a balloon in the heavily polluted air of Shanghai’s Pudong New Area on January 2, 2016. Shanghai Hongqiao Railway Station is the point of departure for the blackened high-speed train. 
A painted pleasure boat drifts in the heavily polluted air on Xuanwu Lake in Nanjing, East China’s Jiangsu Province on January 2, 2016. Nanjing is one of the cities passed by the blackened high-speed train along the Beijing-Shanghai line. 
A building disappears into nothingness, shrouded by the heavily polluted air of Jinan, East China’s Shandong Province on January 2, 2016. Jinan is one of the cities passed by the blackened high-speed train along the Beijing-Shanghai line. 
Skyscrapers stand in the heavily polluted Beijing air with their uppermost floors piercing through into blue skies high above on January 2, 2016. Beijing South Railway Station is the terminal station of the blackened high-speed train. 
A high-speed train sits covered with dust on January 2, 2016, after completing the 800-kilometer trip between Beijing and Shanghai in just over five hours. 
A high-speed train sits covered with dust on January 2, 2016, after completing the 800-kilometer trip between Beijing and Shanghai in just over five hours.
