In the northeast Chinese city of Harbin last week, the air pollution was so thick that schools were closed, traffic became gridlocked and flights in and out of the metropolis were canceled. For years, severe air pollution and rising carbon emissions have been downsides to China’s economic growth, even as that growth has lifted more than 600 million people out of poverty.
It may come as a surprise, then, that China has spent enormously to reduce air pollution and to limit carbon dioxide emissions, the main driver of climate change. In fact, its investments to decarbonize its energy system have dwarfed those of any other nation. And its forceful regulation to reduce sulfur dioxide emissions from power plants may be one of the most swiftly effective air pollution policies ever implemented anywhere. Those emissions fell sharply from 2006 to 2010, according to a new study by Chinese and American researchers that we took part in, preventing as many as 74,000 premature deaths from air pollution in 2010.
So why are China’s efforts at emissions control falling short?
There are several reasons. One of them is China’s instinctual response to such challenges: a top-down approach to try to engineer its way through them according to master plans. The result is that China may be winning battles but not the wars on emissions control, because its faith in mandates has met its match: an economy that is growing too fast, and atmospheric challenges that are too multifaceted for even the smartest planners to tame.
Indeed, air quality in many cities has sometimes been terrible this year, especially in the north. Last January, Beijing’s level of fine particles, 2.5 microns in diameter or under and known as PM 2.5, reached at least 20 times the level recommended by the World Health Organization for a 24-hour period. This prompted a scrambling government to ram through new air-quality protections.
You might think that China’s success in reducing sulfur dioxide, which reacts with other chemicals to form PM 2.5, might have resulted in a lasting reduction of these fine particles, which are dangerous because they penetrate deep into the lung and can enter the bloodstream. But PM 2.5 takes many chemical forms and is produced in many ways, including from other gases.
And this is one reason China’s successful control of sulfur dioxide is hardly incompatible with a rise in PM 2.5 since 2010. In fact, research by Wang Yuxuan and colleagues at Tsinghua University suggests that reducing sulfur dioxide emissions can even increase fine particle levels in north China in winter, because it frees another pollutant, ammonia, to react instead with nitric acid to form PM 2.5. Evidence is also growing that China’s winter climate may be changing in ways that foster episodic accumulation of fine particles, consistent with unusually stagnant meteorological conditions last January.
Such complexities caution against assuming that poor air quality results only from a failure to try to prevent it. The atmosphere is an extremely complicated physical and chemical system that varies by region, and China’s atmospheric knowledge base is still developing. Air quality prescriptions are only as good as the science that informs them, and China’s air pollution is both rapidly evolving and only partly understood.
China’s faltering progress on air quality resembles its record on carbon dioxide. Those emissions have risen by about 8 percent a year since 2007 and increased from nearly 14 percent of global emissions in 2000 to 27 percent in 2011.
This is in spite of China’s enormous investments to decarbonize its energy system. In less than 10 years it has built the world’s largest wind power capacity, with plans to triple it by 2020. Its hydropower capacity, also the largest in the world, is expected to triple from 2005 to 2020, and its nuclear capacity will multiply at least sixfold over that same period. And China is increasing imports and production of natural gas, the cleanest fossil fuel.
But all of this is cold comfort to a Beijing citizen wheezing behind her face mask day after smoggy day, or a Sichuan farmer wondering if climate change is to blame for his declining rainfall.
China’s longstanding reliance on central planning and a piecemeal approach to pollution control may be a cause. Its abatement of sulfur dioxide, for example, resulted from the mandated deployment of scrubbers and forced replacement of inefficient old power plants, motivated by numerical reduction targets to reduce sulfur emissions and increase energy efficiency. Similar targets were included in the current five-year plan, and others have driven the development of low-carbon energy supply and consumption.
This use of national targets and technology mandates reflects the continuing legacy and institutional power of central planning in China. It is also a result of careful study of what has worked in the West. Much of the credit for the largely blue skies in America today goes to command-and-control regulations, and America’s carbon policy consists of similar mandates, notably fuel-efficiency standards for cars and now, proposed standards for new power plants.
But the unprecedented pace of China’s economic transformation makes improving China’s air quality a moving target. Focusing on one key pollutant from one major industry, as China’s planners did from 2006 to 2010, is beneficial but insufficient, because growth in emissions from other sectors and of other pollutants overwhelms the gains. And it is hard to see how China can centrally decarbonize its energy system more than it is already attempting to do, which is not succeeding fast enough to protect the climate.
Many environmental economists lament the inefficiencies of technology mandates, promoting instead policies to put prices on emissions and allow markets, not the government, to determine the best technological responses. If economic growth is overwhelming the best efforts of China’s planners, harnessing the power of markets may offer the most hopeful prospect for a more pervasive, truly economywide, solution.
Carbon can be priced by either a cap-and-trade system, with which China has begun experimenting, or more simply with a tax, as China’s finance minister, Lou Jiwei, and several government research institutes have been promoting.
Like these institutes, our group has studied the impact of carbon tax policies. We estimate that a modest tax on carbon dioxide, starting small and rising to about $10 per ton in 2020, could sharply lower the growth of emissions with little effect on G.D.P. growth and consumption over the long run. In the short run, some energy-intensive industries and segments of the population would incur losses, but the tax revenues offer a source for compensating them during an adjustment period.
This illustrates the same economic reasoning that drives advocacy of carbon taxes globally, including by American economists across the political spectrum.
In China’s case, however, there is a huge bonus that should raise some smiles behind its ubiquitous face masks. Precisely because China’s severe pollution results chiefly from coal and oil combustion, a carbon tax would deliver a potent ancillary benefit: reduced concentrations of an array of air pollutants. We estimate that the same tax would prevent as many as 89,000 premature deaths a year from pollution by 2020, and even improve crop productivity. A larger tax, of course, would bring greater benefits.
While a carbon tax cannot substitute for a comprehensive air quality strategy — including expanded support for atmospheric sciences — it would be a powerful jump-start in the right direction.
This approach offers a real chance for China to limit both carbon emissions and air pollution at little cost to economic growth, all in one relatively straightforward policy. It may be an opportunity that nobody, in or out of China, can afford to ignore.
Chris P. Nielsen is executive director of the China Project at Harvard’s School of Engineering and Applied Sciences. Mun S. Ho is a visiting scholar in economics with the project. They are co-editors of Clearer Skies Over China: Reconciling Air Quality, Climate and Economic Goals.