The purpose of his lecture was to provide proof of why atmospheric carbon is not a pollutant and why humans cannot regulate it.

The effect of fossil fuel on CO2 emissions is minute, Prof. Salby said.  "The fossil fuel perturbation is too small to even be detectable … [It] is presently not detectable.  It will not be detectable, ever."

Science has been taken over by "government bureaucracy under the aegis of the UN."  Its objective, he said in 2016, "has become an exercise in social engineering to predict and control the undetectable."

Who is Murry Salby?

Murry Salby was critical of anthropogenic global warming. His last position in academia was as a professor at Macquarie University, Sydney, Australia. 

According to Wikipedia, in 2013 the university dismissed Prof. Salby on grounds of refusal to teach and misuse of university resources.  DeSmog highlighted on Prof. Salby's profile page that "between 1988 and 2013, Salby committed financial and other offences that led to his departures from faculty positions at two major universities." 

Regarding Macquarie University it appears DeSmog used an in-house report that could not have been accessed without requesting it under the Freedom of Information Act ("FoI"). "DeSmog vaguely suggest there 'must have been an FoI', but there are no links to support that. In the end, a confidential, low standard, internal document with legalistic sounding words, may have been 'leaked' to those in search of a character attack," Jo Nova noted.

Prof. Salby's dismissal from Macquarie University followed a series of unfulfilled commitments by the university, deliberate attempts by the university to sabotage and silence him and a misconduct hearing held by the university while Prof. Salby was in France. As Jo Nova noted at the time: "Is his research is so dangerous to the cash cow that is 'global warming' that it had to be stopped at any cost?"