Climate change: The two-degree target

In December, policy makers will meet in Copenhagen, Denmark to thrash out a new global deal on climate change. The aim is to limit global warming to two degrees Celsius above pre-industrial temperatures. We sent three young climate researchers along with Nature's Olive Heffernan to find out just how much of a challenge this ambitious target will be. Join them as they seek advice from climate experts including the IPCC's Rajendra Pachauri, challenge the sceptical views of political scientist Bjorn Lomborg, and learn lessons from the Nobel Laureates who showed that CFCs were destroying the ozone layer.