Last year, after the US withdrawal from the Paris Accord, China's top climate official Xie Zhenhua assured the world that China's commitment to fight climate change was unwavering.

Now, Zhenhua has announced that China, the world's biggest energy consumer, has already met its 2020 carbon intensity target – a whole three years ahead of schedule.

At a forum in Shanghai on Tuesday, Zhenhua reported that the country successfully cut its 2005 carbon intensity level by 46 percent last year.

For those that don't know, the carbon intensity level is essentially the amount of climate-warming carbon dioxide that a country produces per unit of economic growth. In light of China's booming economy, the achievement is especially encouraging.

The achievement is important, but it doesn't mean that China's overall carbon emissions have dropped. It just means that the country's economy is becoming more efficient.

According to The Hill, the country plans to hit their peak carbon emissions by 2030, although if China keeps investing heavily in renewable energy and efficiency measures, it might reach this target ahead of schedule as well.

While it's certainly good news, China has failed to fulfil its promise to create a nationwide emissions cap and trade system by 2017. Instead, the leaders of China settled for a scaled-back trade system that only involves the power sector.

Even still, it is the largest national market in the world, and Zhenhua says the country will expand the market to other industries soon.

Yet despite all these progressive moves, China still cops a lot of criticism as the number one greenhouse gas emitter in the world.

And while China has taken steps to fulfil the promises of the Paris Accord, some climate activists are worried that China's recent decision to transfer the issue of climate change to a new and improved Ministry of Ecology and Environment will set the country back a step.

Previously, the responsibility fell under the National Development and Reform Commission (NDRC), but now a whole other agency has to learn the ropes.

"It is a daunting task to launch China's national carbon trading market," said Peter Corne, managing partner at the legal firm Dorsey & Whitney in Shanghai, who follows China's environmental policies.

"It is questionable whether in the short term (the new ministry) can be elevated in status and power to the extent that it will be able quickly to assume the influential role that the NDRC occupied in the area of climate change," he added.

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