A new climate change report from the Met Office and its US equivalent has provided the "greatest evidence we have ever had" that the world is warming. The report brings together the latest temperature readings from the top of the atmosphere to the bottom of the ocean
Usually scientists rely on the temperature over land, taken from weather stations around the world for the last 150 years, to show global warming. But climate change sceptics questioned the evidence, especially in the wake of recent scandals like "climategate".