'Greatest show on Earth' opens in Copenhagen

Some 15,000 delegates from 192 countries are descending on Copenhagen on Monday (7 December) for what many are describing as the biggest show on Earth, and, for scientists at least, the most important meeting the world has ever known: the UN summit on climate change.

Officially known as the 15th Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC), or "COP15," the meeting is the culmination of an agreement made by world leaders two years ago in...