You have missed the point of my post. The issue is not the origin of the CO2, but the causal relationship supposedly demonstrated by Gore’s chart. My point was that, historically, the rise in temperature was the cause of the rise in CO2. Gore had, incorrectly, asserted the reverse; i.e., that increases in CO2 had caused the temperature to rise.
The current increase in atmospheric CO2 is usually attributed to the increase in the burning of fossil fuels. This is probably true, but may also be attributed to other causes.
Over the longer run CO2 has also followed weathering although weathering is slow. But the uplift of the Himalayas, Caucasus, Alps, Rockies, etc all contributed to an unusual lowering of CO2 to starvation levels never before seen in earth's history.
The lack of CO2 led to the evolution of C4 plants which further exacerbated the lack of CO2. But mainly the lack of CO2 has led to one of the most protracted cold periods in earth's history. Not the very coldest since there were plausible frozen states, but the longest glacial period, which we are still in.