Just hours after the EPA proposed new limits on GHG emissions from America's existing fossil fuel electric generating units, China announced its own ambitious plans to limit GHGs. Or did it?

On June 3, He Jiankun, vice chairman of China's National Expert Committee on Climate Change, was quoted in several news outlets as announcing that the Chinese government will impose an absolute cap on GHG emissions beginning in 2016. But subsequent statements have characterized the Chinese GHG cap as a proposal, rather than a final policy or requirement. For now, the only certain thing is the absence of certainty.

If China ultimately enacts a firm cap on GHG emissions, it could significantly change the dynamics at upcoming United Nations climate change negotiations in Lima (December 2014) and Paris (December 2015). In the past, the United States has been reluctant to pursue an international agreement on GHGs until developing nations move to limit their own emissions. A meaningful cap on China's GHG emissions would help break that logjam.

Limits on China's GHG emissions could also change the dynamics of the United States' domestic debate over EPA's proposed limits on existing fossil fuel electric generating units. Opponents of EPA's proposal are concerned that it will undermine American economic performance and provide unfair advantages to international competitors. Limits on Chinese GHG emissions would offset those concerns and help make the EPA proposal more politically palatable.