[legion]

You mean the temperature has risen steadily since the Little Ice Age ended 140 years ago? Who da thunk?

[The theory of man-made] Global warming is based on 150 years of temperature measurement and millenia of guesses on what the temperature was in the past.

It's like having 15 seconds of trading information from the open of the stock market on January 2nd, and detailed information on oil prices going back to 1920 that you have used to "extrapolate" what the stock market did for the past 88 years, and then using that information to project how the stock market will close out the year...

And there is another, much simpler explanation for your graph Jim. Most temperature measurement stations are in urban areas. Due to the "heat island" effect, that has skewed the data in favor of higher temperatures. Do a Google search, there is a website that tracks the placement of these stations (and how they are more often than not improperly placed) and discusses this issue. Even many of the stations set up in rural areas are set up in the middle of large, asphalt parking lots--it's almost as if the results are being manipulated to produce a predetermined outcome.