Dreaming of Blue Skies: The Impact of Winter Heating on Air Quality in Northern China

Living under a blue sky has become a dream for many people in China, especially those in the north. If you walk on the street in Beijing on a gloomy day, you will see people wearing masks everywhere due to air pollution. The situation is, however, somewhat relieved in southern China. In “Evidence on the impact of sustained exposure to air pollution on life expectancy from China’s Huai River Policy,” Chen et al. argue that winter heating policy plays an important role in air pollution in northern China. Unlike the United States, China mainly uses coal to produce winter heating, which creates a lot of pollution. The authors conclude that winter heating in China leads to 55 percent higher ambient concentrations of total suspended particles (TSPs) and is linked to a 5.5 year reduction in life expectancy in the north compared to southern China.

Chen et al. begin examining the different levels of air pollution by exploiting China’s winter heating policy. During the central planning period from 1950 to 1980, the Chinese government established a policy to provide fuel boilers with free coal to produce winter heating in northern China. The combustion process in the boilers releases a significant amount of pollutants that can be extremely harmful to human health. Since the winter heating policy has been enforced for a long time and human mobility in China is greatly restricted by the household registration system, the authors study the long-run effect of TSPs on human health.

The authors first collected information on annual daily average concentrations of TSPs for 90 cities from 1981 to 2000 in China. They then collected the corresponding mortality data from China’s Disease Surveillance Points system. Chen et al. classify the causes of death as either cardiorespiratory or non-cardiorespiratory; cardiorespiratory causes of death are closely linked to ambient air quality. A range of other determinants of mortality and life expectancy are used as control variables in the two statistical models the authors adopted. The conventional strategy model employs the ordinary least squares that fit life expectancy with TSPs levels and other determinants of life expectancy. The second approach leverages a regression discontinuity design to measure the impact of TSPs concentration levels on life expectancy.

Chen et al. find that TSPs concentration in northern China is 184µg/m3, or 55 percent higher than in the south, and this impact of the winter heating policy is robust to their different analytic methods. The discontinuity model finds a decrease in life expectancy of about five years in the areas north of the winter heating boundary and that a 100µg/m3 increase in TSPs is associated with a 14 percent increase in the overall mortality rates and a decline in life expectancy of three years. The authors hypothesize that the winter heating policy increases mortality rates by 22 to 30 percent and that this increase is almost entirely due to higher rates of cardiorespiratory mortality.

The winter heating policy, which had the laudable goal of providing indoor heating, turns out to have disastrous consequences for human health. Failure to install sufficient pollution abatement equipment is the major reason, according to the authors. The Chinese government should set stricter standards on the equipment that fuel boilers use to produce winter heating and create energy efficiency programs to incentivize individuals to update their fuel boiler equipment. As the air quality in both northern and southern China is deteriorating, China should reconsider its energy consumption model and enforce environmental regulations more actively. After all, people in China wish to have the privilege to see the blue sky in their lives, instead of their dreams.

Article Source: Yuyu Chen, Avraham Ebenstein, Michael Greenstone, and Hongbin Li, “Evidence on the impact of sustained exposure to air pollution on life expectancy from China’s Huai River policy,” Proceedings of the National Academy of Science of the United States of America 110, No. 32 (Aug 2013): 12936-41.

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