Smoke comes out of a chimney near cables from a high speed train travelling from Beijing to neighbouring Zhangjiakou in northwestern China's Hebei province. China is the world's biggest carbon dioxide emitter, followed by the US. AP Photo
Smoke comes out of a chimney near cables from a high speed train travelling from Beijing to neighbouring Zhangjiakou in northwestern China's Hebei province. China is the world's biggest carbon dioxideShow more