Climate change skeptics claim that the hockey stick graph published by the IPCC is inaccurate, based on flawed models etc. For reference, here is the IPCC chart with a hockey stick superimposed.
What I want to know is how skeptics might explain these two other charts:
If the IPCC chart is wrong, then why is the hockey stick also visible in these other datasets? They are not based on models, but on REAL DATA, and they are from different places in the world, over shorter timespans than the IPCC chart.
Despite these differences, the hockey stick is visible.
But to move on to my real point. Is the possibility that the IPCC is wrong sufficient justification to do nothing about global warming? It is OK to gamble with the long-term future of the planet? Are the lives of billions of people worth risking?
Will those skeptics bet their lives that the IPCC is wrong?
Update 2014: In response to recent flooding in the UK, David Miliband, current leader of the British Labour Party, said: "...the costs of not acting on climate change, in terms of the billions of pounds that are lost in terms of businesses and families, as well as the human costs, are greater than the costs of acting."
So what? Oh no, even if the IPCC is wrong, we get cleaner air and heathier citizens! What is the problem with this?
The rate of change seems a little fast for a natural process, particularly when a plethora of possible anthropogenic causes are present.
Surface thermometers are merely one mechanism for determining temperature. They cannot all be wrong, especially when the data they output looks the same (see above charts).
Wrong - the cooling could have also been anthropogenic in origin - in particular, the effects of the Great Depression in the 1930's.