Statistics: Scientific Consensus on Climate Change?

One of the memes I’ve heard recently in the climate debate is that there is no scientific consensus — that there is actually strong disagreement.

The main basis of this argument is that 31,486 dissenting scientists have signed a petition against the belief that Global Warming is man made at the

I don’t want to debate climate change; rather, I want to look at that argument to see if there are any statistical flaws in it.

My problem is whenever anyone uses a single, out of context, data point. What does this number actually mean? Is 31,486 alot or a little? How many scientists are there in the US? etc.

I heard this argument the other day, and went hunting down a visual way to express it, and found this via Information is Beautiful:



This does not resolve the debate — there are more variations (Climate Change: A Consensus Among Scientists?) — at but it demonstrates an obvious flaw in the “dissenting scientist” argument.

Here is the breakdown of skeptics, by field:

Interesting stuff . . .