The atmosphere is comprised in part of CO2. CO2 absorbs radiation above a certain wavelength, i.e. it heats up. If there is more CO2, there are more molecules warming up, thus the atmosphere is as a whole warmer. Since that occurs even if solar radiation remains constant, one has to say the rising CO2 leads rising temperature. Adding CO2 is like adding a second pane of glass to the greenhouse--the interior warms even while the incoming sunlight does not change.Quote from jem:
no one is saying they have evidence that co2 leads temps.
Some agw nutters at the IPCC were claiming they had models which showed co2 leading temps but those models failed and they were just models anyway.
The shakun study also did some modeling. it claimed that after warming in antarctica... the modeling showed co2 could have led the warming in other parts of the globe.
Ok lets say Shakuns modeling turned out to be good CO2 still trails the warming.