[babar]

1. You assume a (fairly) anonymous, amateur source based on a single data point is more unbiased than someone who has devoted most of their lives to collecting data? I totally agree with the movement to make scientific data more open, but I think you are really underestimating the motivations of most scientists.

2. Extrapolating from a single data set leads to huge biases in interpretation. There are too many uncontrolled variables to say anything meaningful beyond what the temperature in this city has averaged. I think the rate of change that people are worried about in overall temps would probably not even register on this graph clearly.

If you are going to criticize how science is done, you should probably learn more about how it is done.

And some basic statistics.