From the story:
Plimer gets especially upset about carbon dioxide, its role in Earth's daily life and the supposed effects on climate of human manufacture of the gas. He says atmospheric carbon dioxide is now at the lowest levels it has been for 500 million years, and that atmospheric carbon dioxide is only 0.001 per cent of the total amount of the chemical held in the oceans, surface rocks, soils and various life forms. Indeed, Plimer says carbon dioxide is not a pollutant, but a plant food. Plants eat carbon dioxide and excrete oxygen. Human activity, he says, contributes only the tiniest fraction to even the atmospheric presence of carbon dioxide.
There is no problem with global warming, Plimer says repeatedly. He points out that for humans periods of global warming have been times of abundance when civilization made leaps forward. Ice ages, in contrast, have been times when human development slowed or even declined.