Could be it is the wrong way around and the CO2 is rising because of an increase in temperature.
That case was made in the first rebuttal of The Inconvenient Truth and, as far as I know, is still valid.
As I see it the oceans are bludy deep and it is only the very surface which is agitated. There is NO upwelling of cold deep water to recycle detritus etc so it takes a couple of centuries for a warming atmosphere to warm the depths a little and force CO2 out of solution. Same in reverse.
