Sir David King
According to the government's chief scientist, Sir David King, while the evidence continues to grow, what we really need to see is action to avoid the worst impacts of climate change.
"Action is affordable, inaction is certainly not," said Sir David at the Greenpeace Business lecture on global warming in London.
As scientists around the world study the changes in our climate going back almost a million years, they confirm what many of us know, climate change is already here.
