On the environment, China steps up while the US retreats

China’s total carbon dioxide emissions are leveling off. Photo: Reuters

Under President Donald Trump, the United States has seen an impressive run of climate change denial. The rollback of signature climate and environmental initiatives, including Trump’s abrogation of the Paris Climate accord, unsettles those who think scientific and economic consensus should guide policy. Many Americans take a clean environment for granted, ignoring its origins in sound science and responsive policy.

At the same time, China is taking a page from the US playbook – our research shows that China is making independently verifiable progress in reducing sulfur dioxide from coal power plants – and this is good news for the world. Meanwhile, the US has signaled its indifference and even disdain for global environmental progress. How much should we worry?

We focus on recent trends in environmental policy by the two biggest national players: the US and China. Here, the US and China are moving in opposite directions. We argue China’s improved policies are real and, moreover, more newsworthy and significant than the US retrenchment insofar as global emissions are concerned.

China is by far the world leader in greenhouse gas emissions and has been for over a decade. Already in 2015, the US emitted less than half as much CO2 as China emitted. China also suffers from severe local pollution, while progressive policies (begun under President Richard Nixon) have held US companies to high standards. Therefore, the most pressing national venue for enlightened global environmental policy is no longer the US.

Looking forward, China is clearly ground zero for the course of global emissions and climate change, not the US. The world would arguably be in more dire straits if Scott Pruit had Li Ganjie’s job heading China’s Ministry of Ecology and the Environment. This is something for which scientists and our children might be thankful.

China has been adopting increasingly progressive environmental policies. In 2014, China imposed stringent standards on the concentrations of sulfur dioxide. The Washington Post recently reported that China is re-foresting land the size of Ireland. Perhaps most ambitiously, China is implementing a national carbon exchange of the type favored by economists and that former US President Barack Obama was unable to get through Congress.

Ironically, it was the US that pioneered the successful implementation of cap-and-trade, starting with the phase-down of lead in gasoline in the 1980s. Still, there is little mystery in how to structure incentives to find the most ingenious, low-cost ways to reduce emissions. Both cap-and-trade and pollution taxes harness markets to this end. China is adopting policies that have proven effective elsewhere to find these low-cost avenues.

There is increasing reason to believe China’s environmental policies will actually have some bite. On this particular score, there is no shortage of well-earned doubt and suspicion. Time and again, doubts about the reliability of government-provided pollution data have been shown by independent researchers to be legitimate.

Our new research indicates that the situation in China has been improving. Coal accounts for about half of Chinese CO2 emissions, or roughly the same CO2 emissions as the US in total. Coal-fired power plants faced tighter emissions standards beginning in July 2014.

We analyze state-of-the art Continuous Emissions Monitoring Systems (CEMS) data, which are uploaded to publicly available websites but have not been analyzed by academic researchers before. Perhaps dutifully, these “official” data show a prompt reduction in SO2 concentrations around July 2014. What’s striking is that when we benchmark these reductions against SO2 as measured from a NASA satellite, a prompt and significant reduction is also observed: around 18 percent less SO2.

The correspondence with the satellite measures is far from perfect, but clearly there was an important response by many of the biggest coal-fired power plants in the world. And turning to greenhouse gases, China’s total CO2 emissions are leveling off.

Viewed globally this shift in environmental leadership is not as bad as it may seem, and is especially good for China. This is not to suggest that back-sliding on environmental policy by the US is benign. Not only should the US be reducing emissions more rapidly than it is, the US and the world at large need to devise ways to remove past emissions of heat-trapping gases from the atmosphere.

As The Economist magazine has pointed out, most scenarios that keep on a path to avoid the worst of climate change assume that in the future, net greenhouse gas emissions will have to "go negative". As we’re nowhere near that, the scale of the challenge at hand is difficult to overstate. Our point here is that where national governments and their “sovereign” emissions are concerned, China and not the US is the key player.

Fortunately, China has gotten the memo. At a minimum, those who doubt humans’ primary role in global warming (Pruitt) and invoke rocks falling into the ocean to explain sea level rise (Representative Mo Brooks, US House Committee on Science, Space, and Technology) aren’t entrusted with something as globally important as Chinese policy on climate change.

Valerie Karplus, MIT Sloan School of Management

Shuang Zhang, NYU Shanghai and University of Colorado Boulder

Douglas Almond, Columbia University

– Contact us at [email protected]