We've recently seen comments about climate matters from Maurice Newman, the chairman of the Prime Minister's Business Advisory Council, and David Karoly, professor of atmospheric science at the University of Melbourne and a member of the Climate Change Authority.

Newman wasn't completely correct about the Intergovernmental Panel on Climate Change and Karoly failed to mention some critical issues about the IPCC's operation and function. The IPCC certainly has faults and its publicity material doesn't always accord with the facts, but the bigger issues are its narrow charter and how various bodies encourage us to believe that the IPCC is an authority on all climate matters.

Illustration: John Spooner.

The IPCC's charter from the outset has been ''to assess on a comprehensive, objective, open and transparent basis the scientific, technical and socio-economic information relevant to understanding the scientific basis of risk of human-induced climate change, its potential impacts and options for adaptation and mitigation''.

The IPCC's focus is therefore very specific - any human influence on climate. It has no mandate to examine other causes of climate change. IPCC assessment reports claim that the human influence is significant but look closely and we find the claims are based on the output of climate models that the IPCC admits are seriously flawed, that the IPCC often asserts a level of certainty that the data cannot sustain and that as ''Climategate'' showed us, a clique of scientists has in the past sought to control the material cited by these reports.