OK, we did it. A new UN report from the Intergovernmental Panel on Climate Change has found "it is extremely likely that human influence on climate caused more than half of the observed increase in global average surface temperature from 1951 to 2010." That "extremely likely" is important, the New York Times reports—it means the scientists are now 95% to 100% sure global warming is our fault. In the last UN report, they said they were 90% to 100% sure.
The report, which was leaked by Reuters over the weekend, also found that sea levels could rise by more than 3 feet by 2100 if emissions continue at their current rate. An increase like that wouldn't just threaten tiny islands—it could endanger London, Shanghai, Venice, Sydney, and New York, says the Times. However, the scientists warn, because the report won't be published for another month, people should take what they read with a grain of salt. "The text is likely to change in response to comments from governments received in recent weeks and will also be considered by governments and scientists at a four-day approval session at the end of September,” the IPCC’s spokesman says in a statement. "It is therefore premature and could be misleading to attempt to draw conclusions from it." (Meanwhile, a separate study has just named the world's 10 most flood-threatened cities.)