The reality is that, for 90% of the last one Million years, most of North America has been under a couple of kilometres of ice. And man-kind had NOTHING to do with it. Oh, and BTW, the CO2 concentration in the atmosphere was waay lower and did not trigger the retreat of the ice.

Somewhere in between “not at all” and “not one damn bit” is where human effect on the mean temperature of the earth comes in. LOCAL temps, different, mainly because we have cities which have spread and have their own albedo, they are generally hotter than the surrounding countryside, and because the tracking locations of temperatures in those areas have not moved the measurements have increased, but that is an absolutely meaningless number.

Andy May 2:01 am on October 31, 2015
Dr. Harold Lewis, why he resigned from the American Physical Society (APS)
Dr. Harold Lewis was a towering figure in physics. He resigned from the APS and detailed his reasons in an important open letter. In his view government research grants corrupted the APS. The environmental community has tried to demonize privately funded research as “corrupt” so that “pristine” government funding has a monopoly on research. In this way, by controlling the government funding, they can dictate outcomes. Thus man-made climate change becomes “fact,” although all data indicates otherwise. In Professor Lewis’s own words:

“It is of course, the global warming scam, with the (literally) trillions of dollars driving it, that has corrupted so many scientists, and has carried APS before it like a rogue wave. It is the greatest and most successful pseudoscientific fraud I have seen in my long life as a physicist.”