Another interesting fact is that the Earth was 3-5 °C warmer when CO2 levels were 270-280 ppm. The same level that the Earth has had for the past several thousand years while it has been much cooler than it was during the Eemian. If the CO2 level determines the global temperature, then the Earth was broken during the Eemian interglacial because the current theory doesn't work for the warmth of the Eemian.
