I'm sure it has occurred to some people that there may be some truth to the proposition that mankind itself is responsible for rising temperatures somewhere or other. On the other hand some of us who have traveled the world wonder just exactly how does one measure the temperature of the whole earth in the same way we wonder about people who claim that sea levels are rising. How does one measure the rising sea level when the earth is subject to tides from the pull of the sun and the moon and they vary depending on where the moon is in the equation which is why we have spring tides and neap tides.
Nonetheless, I have finally come around to accept that there is some truth to the man made global warming theory. It's caused by a bunch of lying thieves who have slowly been corrupting the climate databases going back centuries so they can lower the observed temperatures in the past and raise the temperatures as they come closer to the present time and by carefully including all the data from sensors in the various heat islands while discarding or massaging the more pristine wilderness sensor observations.
So it is clear to me now that if global warming is man made, it's made entirely with pencils, erasers and computers.