...Flannery, by contrast, ignores peak oil but delves deeply, fluently, even lovingly, into the beautiful complexity of climate science, teasing out the various patterns and cycles that shape climate and explaining how they intersect over time.

One of his conclusions is that we are today in an anthropocene period, in which human activity is one of the patterns shaping our climate. What may surprise you is when this era began.


Bill Ruddiman, an environmental scientist at the University of Virginia, found nothing in the natural cycles [affecting climate] that could account for the stability of our long summer [which began 8,000 years ago after the last ice age], and so he began to look for a unique factor - something that was operating only in this last cycle, but in none of the earlier ones. That unique factor, he decided, was ourselves, and in doing so he revolutionized another recent development - the endowing on our post-industrial times of its own geological period.

The widespread advent of agriculture - cutting and burning forests, planting crops and cultivating swamplike conditions - measurably increased the production of carbon dioxide and methane gas into the atmosphere, forestalling another ice age.