At the big global warming summit in Cancun in December 2010, which saw Mexico having unusually cold weather, a group of leading global warming scientists stated that ending all man made CO2 emissions would not stop global warming.
The only way to stop global warming was to pump millions of tons of sulfur aerosols into the upper atmosphere to reverse global warming.
http://www.umweltbundesamt.de/uba-info-presse-e/2011/pe11-032_large_scale_engineering_in_global_environmental_processes_an_alternative_in_climate_protection.htm