I used to think that global warming was a slam dunk. But then I looked at the data... the carbon makeup of the atmosphere hasn't changed much at all, and we have already reached peak oil. If the carbon sinks (oceans etc.) can hold 2x the current amount they absorbed without much trouble then we are in the clear. Perhaps CFCs and Ozone Depleting Substances present a danger but we have largely reduced their use since t…
global temperature anomaly since 1880 -- http://data.giss.nasa.gov/gistemp/graphs_v3/ carbon dioxide for last 400k years -- http://climate.nasa.gov/vital-signs/carbon-dioxide/
One person I met seemed to think that CO2 would be balanced by algae blooms in the oceans, but he wasn't a climate scientist. Nonetheless, if the ice caps melt enough before CO2 is compensated for, they'll release tons of methane which is an order of magnitude more potent than CO2.
https://en.wikipedia.org/wiki/Arctic_methane_emissions
Here's NASA's site on the evidence for global warming: http://climate.nasa.gov/evidence/
Here's a site that discusses the evidence that humans are at fault: http://www.ucsusa.org/global_warming/science_and_impacts/sci...