Like the other 160-plus signatories of the Paris climate agreement, China has pledged to slash its greenhouse gas emissions in the years ahead as part of a global goal of halting rising temperatures.
"Our response to climate change bears on the future of our people and the wellbeing of mankind," Chinese President Xi Jinping has said.
As the world's biggest polluter, China faces an extraordinary challenge in reducing its emissions — one made all the more difficult because of the countless high-polluting factories scattered across the country.
Authorities have moved to shut down many of the worst-offending factories, but some factory owners simply pay informal "fines" to local authorities before re-opening.
Photojournalist Kevin Frayer traveled to Inner Mongolia with Getty Images earlier this month to capture some haunting pictures of life inside one steel mill.