[cogitator]

40% over a cherry-picked low number.

To clarify, 40% higher than the peak values for the Pleistocene and the Holocene, prior to significant impact due to human activities. I.e., 40% higher than interglacial atmospheric CO2 concentrations. The reason I noted the 40% is that very few people would consider a 40% increase "little".

As far as comparing today's climate to that of the Pleistocene goes, at least that would be comparing it to something that actually existed rather than using climate models that don't represent reality at all.

Models were not mentioned.

[aruanan]

To clarify, 40% higher than the peak values for the Pleistocene and the Holocene, prior to significant impact due to human activities. I.e., 40% higher than interglacial atmospheric CO2 concentrations. The reason I noted the 40% is that very few people would consider a 40% increase "little".

Well, 19th century average atmospheric CO2 was 335ppm. So an increase to 380ppm is about 13%.