A combination photo shows a morning commuter walking in front of the China Central Television (CCTV) building on a smoggy day on December 1, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Damir Sagolj TPX IMAGES OF THE DAY TPX IMAGES OF THE DAY DAMIR SAGOLJ (REUTERS)A combination photo shows the China Central Television (CCTV) building and the Central Business District (CBD) area on a smoggy day on November 28, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Stringer CHINA OUT. NO COMMERCIAL OR EDITORIAL SALES IN CHINA CHINA STRINGER NETWORK (REUTERS)A combination photo shows the giant portrait of Chinese late chairman Mao Zedong on the Tiananmen gate on a smoggy day on December 1, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Kim Kyung-Hoon (top) and Damir Sagolj (bottom)STAFF (REUTERS)A combination photo shows visitors taking pictures at the top of the Jingshan Park overseeing the Forbidden City on a smoggy day on December 1, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Damir SagoljDAMIR SAGOLJ (REUTERS)A combination photo shows people visiting the Forbidden City on a smoggy day on November 29, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Kim Kyung-Hoon (top) and Damir Sagolj (bottom)STAFF (REUTERS)A combination photo shows visitors standing next to a paramilitary policeman as they visit the Tiananmen Square on a smoggy day on December 1, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Damir SagoljDAMIR SAGOLJ (REUTERS)A combination photo shows vehicles traveling past the Central Business District (CBD) area on a smoggy day on December 1, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Jason LeeJASON LEE (REUTERS)A combination photo shows people visiting the National Stadium, or the Bird's Nest, on a smoggy day on December 1, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Kim Kyung-Hoon (top) and Jason Lee (bottom) STAFF (REUTERS)A combination photo shows visitors posing for photographs in front of the Tiananmen Gate and the giant portrait of Chinese late Chairman Mao Zedong on a smoggy day on December 1, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Damir SagoljDAMIR SAGOLJ (REUTERS)A combination photo shows visitors standing next to a paramilitary policeman as they visit the Tiananmen Square on a smoggy day on December 1, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Damir SagoljDAMIR SAGOLJ (REUTERS)A combination photo shows a visitor using binoculars to see the city of Beijing at a viewing deck on the China Central Radio and Television Tower on a smoggy day on December 1, 2015 (top), and on a sunny day on December 2, 2015 (bottom), after a fresh cold front cleared the smog that was blanketing Beijing, China. REUTERS/Kim Kyung-Hoon (top) and Jason Lee (bottom) TPX IMAGES OF THE DAY STAFF (REUTERS)
