Name:   MartiniMan - Subject:   More like guesstimate Date:   5/13/2019 10:46:24 AM

Obviously they weren't monitoring CO2 levels 800K years ago.  They use secondary sources to estimate CO2 concentrations which are fraught with all sorts of uncertainty and error.  So all these numbers and statements of "fact" are wildly uncertain.  But more to the point, even if correct what it means is that CO2 seems not to have the same impact on global climates as much as other factors.  As we have seen over the last two decades global temps are relatively stable despite their belief that we are at "record" CO2 levels.