COPENHAGEN - The head of the U.N.'s panel of climate scientists on Monday strongly defended findings that humans are warming the planet, after critics said that leaked emails from a British university had undermined evidence.

The internal consistency from multiple lines of evidence strongly supports the work of the scientific community, including those individuals singled out in these email exchanges, Rajendra Pachauri told the opening of a 192-nation climate conference in Copenhagen.

Pachauri is the head of the U.N.'s Intergovernmental Panel on Climate Change, which said in 2007 that it was at least 90 percent certain that humans were to blame for global warming.

Skeptics say that emails leaked from the University of East Anglia in Britain show that scientists have manipulated evidence. Pachauri said findings were insulated from tampering by a strict review process.