Carbon and the Anthropocene

Life on earth has created vast stores of detrital carbon the remnants of carbon-based organisms after they have died. These carbon stores range from dead leaves and wood to the fossil carbon in coal, oil and gas. They contain large amounts of usable chemical energy. When the ancestors of modem humans learned to access this energy by mastering fire, they discovered a 'new trick' which led to massive evolutionary advantages for the human species. In the technological explosion of the last two centuries, industrial-scale use of energy flows from fossil carbon has not only transformed human societies and ecosystems, but also caused exponentially increasing accumulation of the released carbon in atmospheric, land and ocean carbon reservoirs. These changes have altered the carbon cycle and other cycles of matter and energy in the earth system, leading to the term 'Anthropocene' for the current epoch. In this epoch humankind is encountering finite-planet vulnerabilities for the first time, as a consequence of the dominance of its home planet bequeathed by the use of energy flows from detrital carbon. Signs of these vulnerabilities can be seen in the contemporary carbon cycle and emerging carbon-climate feedbacks. Interactions between humans, climate, the carbon cycle and other natural cycles are certain to become more profound over the next century and beyond.