"Western governments have pumped billions of dollars into careers and institutes and they feel threatened," said the professor.
"I can tolerate being called a sceptic because all scientists should be sceptics, but then they started calling us deniers, with all the connotations of the Holocaust. That is an obscenity. It has got really nasty and personal."
"Richard Lindzen, the professor of Atmospheric Science at Massachusetts Institute of Technology - who also appeared on the documentary - recently claimed: "Scientists who dissent from the alarmism have seen their funds disappear, their work derided, and themselves labelled as industry stooges."