It's generally an "assumed truth" that CO2 rise corresponds with Temperature rise.
We know CO2 has risen, so we "assume" that our only outcome is warming.
But then reality intrudes on our smugness. ;)
In the Permian we see this sudden rise in temperature, but NOTHING as far as CO2.
CO2 was at a level lower than human history.
Maybe the system is more complex than we thought?