Various sources of temperature anomalies / CO2
(click on each picture for source)

This is what it's like, suspecting problems in Climate Science and starting to investigate. Even the sources are not always as clear as you'd like or as clear as they perhaps should be. Nevertheless, they are still evidence, which, with patience, can lead to further, better, similar sources that reinforce (or challenge, or overthrow) the initial evidence. In this case, however, I've seen so many similar-but-not-identical graphs showing the non-correlation of temperature (up and down) with carbon dioxide (still apparently rising steadily, relentlessly) with good references to one or other of the four main sources of temperature data used by all scientists (GISS, HadCRUT, UAH MSS, RSS MSU) that the basic issue of non-correlation (or at least, very low correlation) is not in any doubt.