Over the next three weeks, in the lead-up to COP 15, the all-important United Nations Climate Change Conference in Copenhagen, World Business will not only introduce you to the people who are witnessing the impact of climate change first-hand, but also to the companies that have pledged and implemented carbon cutting initiatives. Our first report begins in the Arctic, where scientists studying the decline in pack ice have some dire warnings for the world. Our second story looks to China, which has recently overtaken the U.S. as the world's biggest polluter, but some firms are taking serious steps to redress the balance.