Expired · 6th December 2009
If our sense of importance as human beings has been deflated during the last few centuries, we can thank Nobel Prize laureate Paul Crutzen for officially returning us to our previously elevated status. The solar centric idea of Nicolaus Copernicus in the 16th century evicted us from the most privileged location in the universe and the evolutionary theory of Charles Darwin in the 19th century had the humbling effect of revoking our special distinction of being divinely created. But Crutzen's designation of the Anthropocene as the name for the newly emerging epoch in our planet's long history should return our lost sense of importance.
The Pleistocene was the most recent cooling trend that brought the last Ice Age. It was followed by the Holocene, a general planetary warming beginning about 11,000 years ago that melted the encroaching ice sheets and ushered in ten millennia of weather favourable enough for us to develop agriculture. Without this warming, we could never have shifted from hunting and gathering, built the complex structure we call modern civilization, nor could we have increased our population from a few million to nearly seven billion. Crutzen suggests that the word Anthropocene ("human" + "epoch") should designate the next epoch because "humanity has become a globally significant geophysical force" (Simon Lewis of the Earth & Biosphere Institute, writing in the Guardian Weekly, July 31/09.)
The first hint of the arrival of the Anthropocene began less than a century ago when a 2,000-year shift toward another Pleistocene cooling was suddenly interrupted by an atypical warming trend. Some significant force was altering the usual warming and-cooling rhythms of recent geological times. And this force, we discovered, was us.
Although the Anthropocene has stopped another scheduled Ice Age – an event we would be happy to avoid – this unscheduled warming brings with it a plethora of other qualities that are not conducive to our comfort. This is primarily because we have increased our population and expanded our civilization to the limits of optimum climatic conditions. Most changes to climate, ecologies or agriculture are likely to be disadvantageous to us. Rapid and excessive warming, therefore, may prove to be a greater misfortune to us than another slow Pleistocene cooling.
The important word here is "rapid". We can adapt to slow change. But the changes we are causing on the planet are almost instantaneous in epochal terms. The biosphere is not designed to absorb such an impact, and human civilization as it is presently constructed – already stressed to its limits with population and resource use – seems to be in a similar situation.
No one knows if human civilization has reached the zenith of its influence on our planet. Undoubtedly, however, we have already become a profoundly powerful force. Elevated levels of atmospheric carbon dioxide, the highest in nearly one million years, are almost certainly caused by our industrial burning of fossil fuels. As this carbon dioxide is absorbed by the world's oceans, it forms carbonic acid, and the increasing acidity – also the highest in nearly one million years – is beginning to radically change marine ecologies by dissolving the calcium carbonate shells of marine animals. Rising global temperatures mean warmer weather but also warmer oceans, less dissolved oxygen in seawater and impaired conditions for fish. (Marine oxygen levels may not fully recover for 100,000 years.) More carbon dioxide in the air is altering terrestrial ecologies by changing plant growth. Besides upsetting the carbon cycle, we have used so much nitrogen in industrial agriculture that run-off is creating anoxic "dead zones" in the oceans ‹ presently, more than 400 of them totalling 245,000 sq km. Such massive disturbance means the possible extinction of 25 percent of all animals and plants by the middle of this century, the greatest loss in 65 million years.
Not even this is our total influence. As Simon Lewis points out, humans now move more rock, sediment and soil than all natural forces combined. By damming all but a few of the world's major rivers, we now hold three-times as much fresh water in reservoirs as flows naturally to the sea. At least one-third of the planet's land mass has been appropriated for human use. Our removal of 95 million tonnes of fish from the world's oceans each year has depleted commercial stocks by 90 percent and – in this respect alone – we are possibly altering ocean ecosystems beyond recoverable levels. We annually raze 80,000 square kilometres of forest, together with all the diverse species that inhabit these biologically rich places. Our combined effect, when added to other unlisted influences, marks the beginning of the sixth mass extinction in Earth's history. All this qualifies us for having an epoch named in our honour.
This Anthropocene status bestowed by Paul Crutzen has placed us back at the centre of importance on Earth, a distinction we have earned by 10,000 years of heroic effort. The culmination of this effort, together with no other discovered life in the universe, now defines who we are. Instead of inventing religions and philosophies to explain and assuage our perceived victimization by the forces of nature, we are now having to confront and weigh our newly earned reputation as victimizer. With this role comes onerous responsibilities and burdens we have never before had.
The pressures of this test of character are enormous. With our decisions, we are now shaping our own destiny and the destiny of the entire planet. Our choices have become critically important – more important than they have ever been and more important than we could ever have imagined. This awareness should sober each one of us. For we are discovering that our new Anthropocene status – mythologically, it is our second loss of innocence – comes with a totally new definition of ourselves, one we may not want but one we certainly deserve.