The evidence that global temperatures are rising as a result is incontrovertible. The author cites that the historic levels of CO2 have been 180 to 280 PPM, notes that they are currently 380 PPM, and points to that as incontrovertible proof. Sure lets me know why he's a journalist and not a scientist.
A couple of simple points, the first being the most obvious:
Correlation is not causation.
Nobody's proved that there IS a variation in the temperatures yet to my satisfaction.
And you're seeing more and more climate scientists breaking ranks with the global warming theory.
When it comes to "Global Warming" there's a lot of sloppy speech going on. Are we talking about increases in average global temperatures. Are we assuming that these both exist AND are caused by increasing atmospheric CO2 levels. Are we further assuming that increasing atmospheric CO2 levels are principally increased by human activity such as the use of fossil fuels. Are we further assuming that individual transportation is the prime user of fossil fuels. Is the hypothesis that if we quit driving gasoline powered automobiles the world will cool?
Seems like there's a whole raft of "ifs" and assuming going on.