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In some countries, it is up to the residents to decide when to turn on their heating.
In China, it is the government which makes the decision.
At the beginning of November, the government is now regarding the weather as cold enough for radiators to be turned on in certain parts of the country.
In the northern parts of Shanxi province, to the west of Beijing, the temperature has dropped significantly in recent days.
The locals have been battling the sudden cold spell, wrapping up warm and wearing jackets that look like duvets while out on their scooters.
In the city of Shuozhou, the city’s heating started working on October 25. At this point the overnight temperatures were not falling below about 6C. However, only three days later, the temperature at night dropped to freezing.
Meanwhile officials in the cities of Yuncheng, Linfen and Jincheng, in the south of Shanxi, plan to switch on their heating on November 15.
Although the locals may not be able to decide when to turn on their radiators themselves, the heating is heavily subsidised where it is available.
Homes in cities to the north of the Huai River and the Qinling Mountains are provided with central heating, which is largely powered by coal.
Due to the calm, settled weather that the region usually enjoys during winter, this is the season when the pollution is at its peak.
The additional burning of fossil fuels is believed to significantly reduce the air quality. A study published in May 2013 showed that particulate matter in air north of Huai River is 55 percent higher than in the south.