Geoscientist Online

Sir, The March issue of Geoscientist contained a review of “How to Get Expelled from School: a Guide to Climate Change for Pupils, Parents and Punters” (Connor Court, 2011), the latest outpouring from the pen of Australian economic geologist Professor Ian Plimer, an Honorary Fellow of the Society. That book is a sequel to his 500-page blockbuster “Heaven and Earth: Global Warming – the Missing Science” (Connor Court, 2009).

Professor Plimer is a member of the Australian Climate Science Coalition, a group that is highly sceptical of anthropogenic global warming (AGW). He makes it plain in his books and in videos on the web that his stance is profoundly anti-environmentalist, and both his books give the impression that he might be proud to be thought of as a crusader against the concept of AGW.

I find Plimer’s texts difficult to read because he seems confused on fundamental issues. He is happy to tell us on p.126 that carbon dioxide is a greenhouse gas that helps to keep the planet habitable, on p.127 that there is no evidence that human emissions of carbon dioxide drive climate change, but on p.128 that if the current levels of CO₂ doubled temperatures would increase by 0.2°C. Which is it to be? In any case, the vast majority of climate scientists disagree that doubling CO₂ would have so little an effect. Even sceptic Richard Lindzen of MIT would have a doubling of CO₂ raise temperature by about 1°C, while NASA’s Jim Hansen says it will be 3°C, based on paleoclimatic evidence. Who is advising Plimer, one wonders?

“The story of planet Earth is a marvellous chronicle written in stone.” Plimer writes. “The only way to understand climate is to read the rocks because the present derives from the past.” True. So in that case why does his latest book gloss over the Paleocene-Eocene Thermal Maximum, when a massive injection of carbon into the atmosphere caused it to warm by 5-6°C, and the enhanced carbon dioxide concentration in the ocean caused it to become slightly less alkaline thus raising the carbonate compensation depth and removing carbonate oozes and calcareous benthic foraminifera from the deep ocean?

What’s more that event lasted, the geological record tells us, for 100,000 years before things returned to normal (see October 2011 issue of National Geographic for a general description). Isn’t this close to an analogue for what is happening today, as the Geological Society of London’s climate change statement suggests? Doesn’t it contain warnings as to our possible future if emissions increase? So why does he ignore its implications? Perhaps it is one of those ‘Inconvenient Truths’ for the anti-environmentalist Plimer manifesto. Could we ask him to enlighten us with his views?