Here’s a better graph of CO2 and temperature for the last 600 million years! As noted, CO2 levels have historically been quite a bit higher than current levels Joe!
You might note that at 4400 ppm, the earths temperature was roughly the same as it is today! AND an ice age occurred while CO2 was over 4,000 ppm!
So what is the AGW scam really about? Global income redistribution, as admitted by IPCC officials!
Interesting that Romm’s graphs show a much lower level of atmospheric CO2 than actually existed! Note how much higher the average global temperature has been, than it is today! We live in a temporary low temperature bubble!
In the last 600 million years of Earth’s history only the Carboniferous Period and our present age, the Quaternary Period, have witnessed CO2 levels less than 400 ppm.
Global Temperature and Atmospheric CO2 over Geologic Time
Late Carboniferous to Early Permian time (315 mya — 270 mya) is the only time period in the last 600 million years when both atmospheric CO2 and temperatures were as low as they are today (Quaternary Period ).
Temperature after C.R. Scotese http://www.scotese.com/climate.htm
CO2 after R.A. Berner, 2001 (GEOCARB III)
There has historically been much more CO2 in our atmosphere than exists today. For example:
During the Jurassic Period (200 mya), average CO2 concentrations were about 1800 ppm or about 4.7 times higher than today.
The highest concentrations of CO2 during all of the Paleozoic Era occurred during the Cambrian Period, nearly 7000 ppm — about 18 times higher than today.
The Carboniferous Period and the Ordovician Period were the only geological periods during the Paleozoic Era when global temperatures were as low as they are today. To the consternation of global warming proponents, the Late Ordovician Period was also an Ice Age while at the same time CO2 concentrations then were nearly 12 times higher than today — 4400 ppm.
According to greenhouse theory, Earth should have been exceedingly hot. Instead, global temperatures were no warmer than today. Clearly, other factors besides atmospheric carbon influence earth temperatures and global warming.
And Joe Romm insists the records must be wrong? The sky is falling? The emperor has new clothes?