Air temperature and carbon dioxide
Scientists have found (and there is very little disagreement about this, even among strong AGW supporters) that temperature increases occur on average 800 years before the CO2 starts to increase.  This contradicts political claims (by supporters of the global warming treaty) that CO2 drives temperature.
You certainly find an association between carbon dioxide changes and temperature changes. Now, scientists have been very careful to just call it an association without identifying which is the cause and which is the effect. Politicians have been less careful. In fact, our Vice President, Al Gore, has a standard presentation where he shows the results of the Antarctic ice core (called the Vostok core), and you see changes in temperature and changes in carbon dioxide. And he points to this and says, "You see? These carbon dioxide changes caused a temperature increase in the past." Well, it's not so. In fact, in early 1999, there was a paper in Science in which they have now gotten adequate resolution so they can measure which came first, the temperature change or the carbon dioxide change. And guess what? The temperature change came first, followed by the carbon dioxide change about 600 years later. This means that something changed the temperature, not the carbon dioxide. But then as the climate warmed, more carbon dioxide apparently was released from the ocean into the atmosphere. 
John Sununu said: