The consensus for anthropogenic global warming

This is from back in February of 2006, but A Few Things Ill Considered has a nice list of statements from scientific organizations endorsing anthropogenic global warming that includes NASA's Goddard Institute of Space Studies, the National Oceanic and Atmospheric Administration, the Intergovernmental Panel on Climate Change, the National Academy of Sciences, the Royal Society, the American Geophysical Union, the American Institute of Physics, the National Center for Atmospheric Research, and, perhaps most interestingly, British Petroleum, the Shell Group, and, in the comments, ExxonMobil. A number of the links are broken at this point, but I was able to find numerous statements about the reality of anthropogenic global warming on the Shell web pages with a Google search for "global warming site:shell.com".

Science isn't a matter of popular vote, but when a scientific consensus is established it certainly puts the burden of proof on the challenger.