Responding to the CO2 Coalition's "Fact #4" on the Last Four Glacial Advances

CO2 Coalition's "fact #4" is virtually identical to its "fact #1" but just on a different time scale. All they did with this "fact" is change the scale and repeat the same lies with the same dose of alarmism. Rather than showing a climate model of CO2 for 140 million years, they show proxy evidence for CO2 for the last 420,000 years.

They simply repeat here that CO2 fell to ~180 ppm, and we should be alarmed by this because below 150 ppm "terrestrial plant life cannot exist." And if you're not sufficiently scared by this lie, they reinforce it and then imply the fossil fuel industry saved us from a mass extinction. 

We came within about 30 ppm (30 molecules out of every one million) to the extinction of most plant life on land, and with it the extinction of all higher terrestrial life-forms that depend on it. Bear in mind that, before we began adding CO2 to the atmosphere, we weren’t sure that we wouldn’t cross that critical 150-ppm threshold during the next glacial period.

The only new lie in this that isn't explicitly stated in their "fact #1" is their claim that CO2 at ~180 ppm is "thought to be the lowest in the Earth’s history." Except it wasn't. Even in the Phanerozoic, CO2 levels spent about 1 million years at ~100 ppm. We went over all this before when I responded to "fact #1," so I don't feel the need to go over it all again.

The Earth's temperature has also lowered to temperatures in which glacial ice extended into the tropics (called "slush ball earth" episodes) and even to the equator (called "snowball earth" episodes). These were during Precambrian times. But we don't have to worry about this because CO2 is much higher now and increasing at rates that are likely unprecedented in geologic history.