The present level of atmospheric CO2 concentration is almost certainly unprecedented in the past million years, during which time modern humans evolved and societies developed. The atmospheric CO2 concentration was however higher in Earth’s more distant past (many millions of years ago), at which time palaeoclimatic and geological data indicate that temperatures and sea levels were also higher than they are today.

1.       “ Anders Levermann et al, June 2013 PNAS

Climate Facts

Paleoclimate


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CO2 Concentrations Last 800,000 Years
The atmospheric concentration of CO2 is continuing to increase at about 3.2ppm/year, having surpassed 400ppm for several months in 2014.
Temperature vs Sea Level

“The multimillennial sea-level commitment of global warming