What % of CO2 found in the atmosphere occurs naturally verses man made CO2 like polution?

Answer 1

The highest levels of pre-industrial atmospheric CO2 recorded were on the order of 270 ppmv. Current levels are approximately 350 ppmv. Thus, man-made CO2 is approximately 22% of the current atmospheric CO2.

Answer 2

Most of the CO2 is natural, but that doesn't tell the story. There is a natural "carbon cycle" which recycles carbon dioxide. But it's a delicate balance.

We're messing up that balance by digging up carbon the natural cycle buried over a very long time, and burning it really fast. That overwhelms the natural process.

You can see it clearly in this carefully measured data.

http://scrippsco2.ucsd.edu/graphics_gallery/mauna_loa_record/mlo_record.html

The small teeth are the natural cycle in operation. CO2 goes down a little during the summer, when plants are active, and up a little in the winter. The huge push upwards is us burning fossil fuels.

We need to do something about that.

Answer 3

CO2 is CO2 The plants have cleaned it up so it is 30 to 40 ppm.

Answer 4

About 97.75 % natural if you include cow farts and beaners.