The China Central Television (CCTV) headquarters (left) is obscured by severe smog in Beijing on Nov 4, 2016. Beijing issued an orange alert for smog on Thursday afternoon, with visibility in some areas dropping to below 100 meters on Friday. A cold air is expected to blow across the city on Saturday, which could reduce or even disperse the heavy smog as temperatures drop sharply, according to the local meteorological station. [Photo/VCG]