Given that global warming is “unequivocal”, to quote the 2007 IPCC report, the null hypothesis should now be reversed, thereby placing the burden of proof on showing that there is no human influence [on the climate]. http://wattsupwiththat.com/2011/01/15/unequivocal-equivocation/#more-31727
I don’t have a lot to add to the content of this article that counters the assertion that skeptics should have to prove that man isn’t the cause of global warming or the more nebulous concept of climate change or climate disruption.
I will ask one more question. If the human race indeed had the power to influence climate (a questionable proposition), would we use that power to warm the climate or cool it down?
The study on the correlation between weather patterns and societal disruption could provide some interesting background reading to inform discussion. http://archive.fcpp.org/blog/?p=244