So here a link to a report that I found interesting.

The basic upshot is that this scientist, Wolfgang Knorr, did a study to see what has happen to the atmospheric fraction of carbon dioxide over the last 150 years. The assumption is that increasing fractions of carbon dioxide will drive a ‘greenhouse effect.’

In contradiction to some recent studies, he finds that the airborne fraction of carbon dioxide has not increased either during the past 150 years or during the most recent five decades.

I found that very interesting.