For this FactCheck, The Conversation asked Senator Jacqui Lambie for sources to support her statement that “we’ve always had climate change – it’s been much, much hotter and much, much colder. And even 110,000 years ago, it was four degrees hotter.”
A spokesman for Jacqui Lambie referred The Conversation to two books about climate change: Al Gore’s An Inconvenient Truth (2006) and Tim Flannery’s The Weather Makers (2001). His response, edited below for clarity, said:
In a time when everyone says the science is settled, it’s clear that not every one understands the basic science of climate change – and they deny, perhaps through ignorance, the science of natural climate change.
When it comes to climate change, most people think that the average world temperature has been constant for millions of years. Gore and Flannery’s books prove it hasn’t.
Flannery admits that the average world temperature has naturally and regularly increased and decreased over millions and millions of years because of variations in Earth’s orbit and angle tilt. (See attached pages 41 and 42)
Flannery writes about a climate pioneer – and respected scientist – called Milutin Milankovitch who explains in detail why natural climate change is so regular, strong and causes the ebb and flow of ice ages.
Indeed, if you asked this question, most people would be clueless: What’s the average world temperature? In other words, what’s the temperature that we don’t want to increase – because that would mean global warming? Two or three degrees above what base line temperature?
Flannery reveals it early in his famous book on page five at ‘around 14 degrees.’ Recent media reports in the Economist say its between 14.5C and 15C.
So now for the important reference: Al Gore’s: An Inconvienient Truth
We can’t find anywhere in Gore’s book where he actually states what the average world temperature is. However, he draws it in his famous graph where he compares both CO2 levels and average world temperature levels for the last 650,000 years.
Ice core samples from the Antarctic allow for the accurate calculation of average world temperature.
It puts climate change into context. It’s ridiculous trying to justify or talk about climate change when people talk time periods of 10, 20, 50 or 100 years. 5,000 year blocks is just a starting point for a sensible conversation.
So I’ll send you the original pages of Gore’s books – and our modified pages where we’ve drawn a red line and traced back average world temperature for the last 650,000 years and made some comments
(Editor’s note: you can see a clearer version of the original chart here):
When asked by The Conversation if Senator Lambie was representing his work accurately, Tim Flannery said:
I’m happy to hear that Senator Lambie is reading The Weather Makers. She is certainly correct that Earth’s climate has varied greatly over geological time. 110,000 years ago, however, Earth was not four degrees warmer, but around as warm as it is today.