I did forget to answer this. What if warming temperatures actually cause the increase CO2 we're seeing and not vice versa? We do know that warmer temperatures increase the rate of decomposition, and decomposition releases CO2 and methane among other gases.
I've never been convinced that the resolution of ice core CO2 data is actually high enough to say that the CO2 has never been higher. It's not because I'm denying climate change. Climate change has occurred since the beginning of the earth as a planet. I question it because that's what we should always do in science.
How much CO2 from the atmosphere is actually trapped in ice? How much CO2 is lost from the ice? It isn't a static gas even when dissolved, always moving toward an area of lower concentration. The warming of a cold carbonated beverage easily demonstrates this. How much did the melting and refreezing of the snow that created the ice that is sampled today affect the amount of CO2 in it? Our knowledge in this area is based on models. What if the models are missing something, or lots of somethings? Can we really compare 900,000 year old ice with ice formed in the last 100 years and expect to have enough correlation to make accurate predictions?
What would an ice core sample taken 900,000 years from now show? How much trapped CO2 would be lost or gained in the ice core sample representing today?