A photo taken from the China Zun, a skyscraper under construction in Beijing, shows the city being shrouded in heavy smog on Friday. Photo: VCG via Getty Images

Two studies have highlighted major contributors to smog in China, with one attributing Beijing's air pollution to people's pursuit of better basic education.

As the government has been equivocating on the direct sources of air pollution in part due to fears that it may put a brake on China's economic growth, researchers from Beijing's Tsinghua University, one of China's top research universities, and the Health Effects Institute, a Boston-based nonprofit, independent research organization providing impartial and relevant science on the effects of air pollution on health, have released a report, in which they said that coal burning was responsible for about 40 percent of PM2.5 in China's atmosphere, with its contribution in the provinces of Guizhou and Sichuan hitting nearly 50 percent.

The researchers ascribed 916,000 premature deaths in 2013 to ambient PM2.5, which has been the 5th leading risk factor for mortality after hypertension, smoking, high consumption of sodium and low consumption of fruit. The study also attributed 155,000 deaths in 2013 related to ambient PM2.5 to industrial coal burning, 86,500 deaths to coal burning at power plants and 137,000 deaths to transportation. Domestic biomass and coal combustion was another important source of mortality related to ambient PM2.5 that year, resulting in 177,000 deaths, the study concluded.

The Global Burden of Diseases study, the largest and most comprehensive effort to date to measure epidemiological levels and trends worldwide, estimated that exposure to ambient PM2.5 led to 2.9 million premature deaths in 2013, with 64 percent of those taking place in China, India and other developing countries in Asia. Premature deaths caused by PM2.5 exposure were also high in Eastern Europe. The study also said that the population-weighted mean concentration of PM2.5 in China in 2013 was 54 micrograms per cubic meter, with the population-weighted PM2.5 concentration of the northern provinces higher than that of the southern provinces.

On the culmination of air pollution in China this year, a media report said that people in China's southern provinces could live 5.5 years longer than those in the northern parts, citing the fact that northern China is home to an array of coal-burning wheel, cement and power factories, where concentrations of PM2.5 are the highest.

According to the BP Statistical Review of World Energy 2016, in 2015, coal consumption in China accounted for over 50 percent of global total, which means that China consumed almost as much coal annually as all other countries combined. But 2015 saw the second straight annual decline in China's coal consumption due to economic slowdown, higher production of renewable power, increased natural gas consumption and rising demand for electricity.

The decline in coal consumption in China over the past two years is supposed to be the result of a plan the Chinese government announced in 2013 to reduce dependence on coal use amid public discontent over the intolerable air pollution. The core goals of the plan are to reduce coal use in the smog-torn Hebei province, which surrounds Beijing, cut coal use by 40 million tons in 2017 compared with 2012 and lower the density of PM10 and PM2.5 in these areas.

Earlier this year, China announced to suspend approval of new coal mines for the next three years and to cut coal's share of its energy consumption to 62 percent in 2016. But some foreign media reported that China did not fully enforce the plan citing the number of new coal plants as proof.

As one of the world's biggest emitters of greenhouse gases mainly due to coal burning, China has vowed to cut its greenhouse gas emissions per unit of GDP by 60-65 percent from the 2005 levels, increase the share of non-fossil fuels in its energy consumption to 20 percent by 2030 and put a peak on its growing carbon dioxide emissions by 2030.

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Recently, scholars from three Chinese universities including Tsinghua University, Shanghai Jiao Tong University and Shanghai University of Finance and Economics attributed Beijing's traffic congestion and the consequent pollution problems to long-distance drive-to-school trips in a report published in the journal Transportation Research Part D: Transport and Environment.

The study said that it was the parental obsession of enrolling children into famous schools typically located in the districts of Haidian, Dongcheng and Xicheng in Chinese capital that resulted in the drive-to-school trips which should have been avoided by reasonable allocation of educational resources.

At present, about 70 percent of the top-ranking elementary and middle schools are located in the three districts in inner Beijing, while some 70 percent of the city's population lives in the outskirts.

Citing data from Beijing's transportation authorities, the study discovered that about 15 percent of the daily traffic flow during rush hours was contributed by the drive-to-school trips, which could be used to explain why the density of inhalable particles during weekends or holidays was 20 percent lower than that during school days.

The study also showed that 40 percent of students studying at a good school in the district of Haidian would be driven to school by their parents, compared with 11.1 percent students studying at an ordinary school in the vicinity of the good school in the same district.

In light of it, the researchers called for the Beijing municipal government to centralize the power to deploy educational funds and make a comprehensive arrangement about how to allocate educational resources.