Here’s a 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.
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.
We are currently at 400 ppm of Co2 and the alarmists are saying it is causing the earth to warm. FACT: An ice age occurred while CO2 was over 4,000 ppm. So please explain that.
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, it has always been multiples higher than today.
The chart below shows that Co2 levels and temperature are not corelated at all.
Global Temperature and Atmospheric CO2 over Geologic Time
FACT: Carbon levels were many many times higher before humans ever even existed, 7000 ppm down to todays level of only 400 ppm.
ICE HOUSE or HOT HOUSE?
During the last 2 billion years the Earth’s climate has alternated between a frigid “Ice House”, like today’s world, and a steaming “Hot House”, like the world of the dinosaurs.
This chart shows how global climate has changed through time. 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.