China's special representative for climate change affairs Xie Zhenhua speaks at a side event at the ongoing Conference of the Parties (COP24) to the United Nations Framework Convention on Climate Change in Katowice, Poland, Dec. 13, 2018. Former U.S. Vice President Al Gore on Thursday hailed China's leadership in tackling climate change, saying that China is "one of the few countries on track to meet its Paris? commitment." (Xinhua/Chen Xu)