33 eerie photos show just how polluted China's air has become

• As winter approaches, China has ordered its northern cities, along with Beijing and Tianjin, to cut emissions by 4%.
• The government also ordered more than 5 million households to stop using coal heaters.
• These eerie photos show why China has spent the last six years aggressively trying to cut down its pollution.
• Visit Business Insider's homepage for more stories.

Although no one knows the exact amount of carbon that China emits each year, the country has some of the most polluted air in the world.

As winter approaches, and people crank up the heat, China's government is ordering than 5 million homes to stop using coal heating, and switch to gas or electricity, by the end of October.

China also ordered 26 of its northern cities, along with Beijing and Tianjin, to cut PM2.5 emissions by 4%. PM stands for particulate matter, a mixture of solid particles and liquid drops in the air, that damages lungs.

The country has been trying to cut down its pollution for the last six years. At the end of 2016, pollution got so bad that an "airpocalypse" halted everyday life in Beijing. Cars couldn't be driven, planes were grounded, and schools had to be temporarily closed.

Here are 32 photos showing life in China, through the smog.

Jack Sommer and Cyrus Engineer contributed reporting to a previous version of this article.

The smog usually gets worse in the winter months as coal is burned to heat buildings. Coal, the worst polluting energy source, makes up 60% of the country's energy.

Source: Reuters

This aerial photo shows a polluted day in Shenyang, Liaoning province in 2016.

Two people ride during heavy smog in Lianyungang, Jiangsu province in 2017.

A tree sits between two buildings that tower through the thick smog in Jinan, Shandong province.

The "view" from the Jin Mao Tower in the Puxi district of Shanghai amid heavy smog.

A man cooks in open air during a "red alert" day in Hebei province.

Smog looms over the city of Tianjin, in northeastern China.

Bike riders wear masks to help filter the air they breathe.

This woman exercises wearing a mask in Hefei.

Masks can help filter out a particulate matter called PM2.5, which can get stuck in the lungs and lead to conditions like asthma and chronic lung disease.

Some take more drastic measures to guard themselves from the pollution, such as this man wearing a full-on respirator in Beijing.

Everyday work doesn't stop in the smog — here, workers clean the exterior of the Shanghai World Financial Center.

A paramilitary police officer stands guard in front of a portrait of the late Chairman Mao Zedong at Tiananmen Square.

People are seen on the street in smog during a polluted day in Shenyang, Liaoning province.

A woman wears a mask on a polluted evening in Beijing.

Boats pass along the Huangpu River next to the financial area of the Pudong New District amid heavy smog in Shanghai, China, in November 2015.

This combination photo shows Shenyang's skyline on a smoggy day vs. a clear day in 2013.

The lights of downtown Shanghai appear dim due to the haze.

In Harbin, a traffic policeman has to help navigate commuters since they can barely make out the headlights in front of them.

The smoke billowing from a nearby steel plant doesn't seem to bother this girl as she reads on her balcony in Quzhou.

A statue of China's late Chairman Mao Zedong stands tall in Shenyang amid the haze.

Despite the poor air quality, cleaners work along the median of a main road in central Beijing.

People walk on the Bund, a waterfront area near the financial district of Pudong in downtown Shanghai.

A woman strolls through polluted air in front of a construction site of a residential compound in Wuhan.

Smoke from a refinery's chimneys and cooling towers rises above the skyline in Ningbo.

A woman walks across the street during a particularly smoggy day in Changchun.

Citizens walk across a bridge, their line of sight extremely short due to the thick smog.

A woman makes her way through traffic in Changchun.

A man wanders through the smog in Tianjin.

High-rise buildings are shrouded in heavy haze all the way up to the top of the Qingdao development zone.

An electronic screen's brightness shines through this smog in Shenyang.

The tops of these residential compounds in Wujiaqu just barely make it above the smog.