Yes, that's what I think I'm understanding here. The CO2 levels and the global temperature levels tracked each other almost exactly in that 800,000 year chart. The CO2 should be measurable in ice cores, but don't know what proxy they were using for temperature. I'm reserving a slight suspicion that the temperature chart might have just been a hypothetical projection of CO2 by the chart's creator, and then confused by someone else as an amazingly close correspondence. Otherwise, maybe they could get temperature by the ratio of some other chemical in the ice, perhaps O2:O3, or something. Assuming the plots are really independent, I suppose the oceans release more CO2 when they warm, and absorb it back again when the climate cools. In that case, CO2 would fluctuate with temperature in pre-modern times, and shoot up in modern times when we burn all that fossil fuel. But that's an extraneous input that might have little influence on temperature.