Geologist, Professor Ian Plimer: The question of whether or not the planet is warming is entirely dependent on when you start measuring.
“If you started measuring in the 1850s, there’s been a general warming of about 0.7 degrees Celsius… If you started to measure from the medieval times, we’ve had a cooling of about four degrees Celsius… So if you’re telling me that the planet’s warming, my question is, since when?”
Full interview: https://www.youtube.com/watch?v=EPzzoHIyQ6I
