[Hot Tabasco]

95% of all the CO2 in the atmosphere comes from nature itself. Only 5% is man made.......

[palmer]

The rise from 0.028% to 0.042% currently is almost entirely manmade. Without deforestation and fossil burning the rise would have been from 0.028% to about 0.03% or a bit higher, from ocean warming following the Little Ice Age. The idea that 95% of CO2 is natural comes from the annual cycle. There is at last 20 times more natural CO2 created each year than man-made. In the autumn. But the same amount is absorbed in the spring, by nature. So it doesn't add to the total over the years.