Polar bear research shows global warming is real

Harvard Professor James McCarthy was among a handful of top scientists who coordinated a remarkable report by the world scientific community in 2001 that said global warming is real, it’s here, and it’s going to be worse than we thought. “We already see effects that [indicate] the change in climate has occurred,” said McCarthy, who co-chairs one of three working groups of the United Nation’s Intergovernmental Panel on Climate Change (IPCC). “And the projection of some of those [effects] into the future are not a pretty scene.” John Holdren, Heinz Professor of Environmental Policy at Harvard’s John F. Kennedy School of Government, credited the IPCC with largely ending the debate over whether human-induced climate change is happening.