The world’s largest emitter just delivered some good climate news—for now

China is the world’s largest single greenhouse gas emitter, spewing more than double the amount of heat-trapping chemicals as the next biggest climate polluter, the United States .

For the first time, China 's emissions have actually fallen even as energy demand went up.

The decline of emissions in China is a big step toward this international goal, and the timing puts it on course for its own climate targets.

To make China 's emissions reductions durable, there needs to be more stringent policies and enforcement to curb climate pollution within the country.

Clean energy technologies would need to get cheaper, and new ones would have to be invented.

Meanwhile, US emissions are also seeing a slight downward trend, but the Trump administration’s push to extract more fossil fuels, cut incentives for clean energy, and roll back efforts to curb greenhouse gases.