The proportion of people living in abject poverty nowadays has also sharply declined. Educational opportunities, particularly for women, have greatly increased. Since 1990, life expectancy at birth has increased globally by six years, to an average of 70 years of age.39
The benefits of modern life are myriad: the use of a simple plastic cannula can save the lives of both mother and child at birth; driverless cars can take us, as if by magic, anywhere we want to go; research laboratories make it possible for billions of people to give free rein to curiosity. The late twentieth and early twenty-first centuries represent a time of incredible expansion of the human comfort zone, certainly for those who have the means and have never suffered the acute violence of war or the slow violence of poverty.
Without this new economy, without industrial-based agriculture or pharmaceuticals or fossil fuels, most of us would not be alive. Some people sound as if they would welcome a scenario of fewer people. The “population bomb” has been widely used as a metaphor. But in my opinion, the mere number of people is not the problem in the dawning Anthropocene. Being German, with the backdrop of my country’s National Socialist past, I wouldn’t want to imagine how a certain population number is considered “too many.” Who is the perpetrator and who the victim in such a scenario? I think that every new person enriches earth with his or her potential for consciousness, creativity and community. I am not someone who would prefer only one billion people (instead of seven or eight) to be living on earth, nor am I like Stephen Emmott, who finds a world population of ten billion to be a terrifying vision.40
I believe that the Anthropocene idea can help people see themselves as active, integrated participants in an emerging new nature that will make earth more humanist rather than just humanized. It would be absurd if an idea named the “Anthropocene” were characterized by a negative view of humans!
But even the most positive attitude toward humanity cannot save us from having to face up to the enormous—literally earth-shattering—developments at the end of the Holocene. Our population numbers signal ever growing consumer demand, ever more areas of land claimed by people, ever increasing energy consumption with its consequences for the climate, and new influences on evolution. Attentive readers will already be familiar with some of these factors. But only when looked at as a whole, do they create the broad overview necessary to see how the Holocene is coming to an end and something new, the Anthropocene, is beginning. Our individual actions, multiplied by the number of people who are alive and make decisions, is a new reality that is hurtling towards us with such velocity that its consequences, both positive and negative, surprise us.
If your head starts spinning at the huge numbers being mentioned here, just remember that these figures derive from the totality of many small actions. Millions of tons of eroded soil start with the food harvested from one industrially farmed field. Billions of tons of carbon dioxide emissions start with the flick of a switch, whether to turn on a light or a car engine. All the phenomena of the Anthropocene—whether positive or insane, surprising, funny or creative—start with small actions. When you buy a ballpoint pen that has a tiny, man-made crystal on the tip, you are thereby increasing the variety of Earth’s minerals, something future geologists may wish to investigate. When you add another ton of carbon dioxide to the atmosphere, your descendants might swear at you long after you are gone.
There are four major factors determining the end of the Holocene. The first is population growth. If the number of people living today was the same now as at the time of Jesus Christ—a few hundred million—their collective impact would not be sufficient to initiate a new geological epoch.
In the year 1800, there were one billion people; in 1930, two billion and in 1960, three billion. In October 2011, the seventh billionth person was born: Danica May Camacho of the Philippines was chosen by the United Nations to have this starring role.41 If the world population was evenly distributed across the Earth, there would be fifty-three people per square kilometer of land (excluding the Antarctic).
By the middle of this century, according to United Nations forecasts, another two billion people will be added to the world population, which is equivalent to the number of people who were living on earth between World Wars I and II. This also means that by 2050, there will be about 140,000 more births than deaths, per day. By these calculations, a city with the population size of Los Angeles will be added to the world every month.
By the middle of this century, fifty-three people per square kilometer jumps to sixty-six people per square kilometer. All this growth is taking place mainly in developing countries. In other words, humanity is increasing every day by one Indian slum, one high-rise community in Beijing, one outlying district of Jakarta or one medium-sized town in the Congo.42 Just the number of people on earth does not signify much: The greater impact comes from our way of life by which this number must be multiplied. Our consumption habits determine how much land, how many industrial and mining areas and how much urban space is necessary to sustain this number of people, not only their survival but also their happiness.
The second factor that marks the end of the Holocene is the enormous increase in human living space requirements. Only a quarter of the Earth (about 7,000 square kilometers or 12 million square miles) is arable land that is suitable for growing food for human consumption. By 2007, cities and communities had already extended over an area half the size of the Australian continent, and this area is expected to grow considerably in the next decades.43 Cities are really efficient at housing people, but nevertheless need a lot of energy and resources to be built and maintained. Gigantic quantities of concrete and other building materials are being produced, transported and deposited in order to create new settlements. Jan Zalasiewicz, a geologist at the University of Leicester, describes urbanization as “an alteration in sedimentation processes via the construction of man-made rock strata.” Concrete is a key material in this process: “The global annual production is now approaching five billion cubic meters, that is something over two-thirds of a cubic meter for every man, woman and child on Earth, in total enough to cover all of Germany, Austria and parts of neighboring countries under a centimeter-thick layer of this stuff—each year. It is part of the urban stratum, rising above the ground surface as our homes and factories, and extending below it as foundations, metro systems, sewers, electrical cables, and yet deeper as mines and boreholes.”44
Dams, mines and human-induced erosion also comprehensively alter the geological state of the earth. Tens of thousands of hydroelectric dams stop enormous quantities of sediment from reaching estuaries.45, 46 Erosion caused by industrial agriculture moves ten times the volume of sediment than was the average 500 million years ago.47 Material flows of such essential elements as phosphorous and nitrogen, both of which are used in artificial fertilizers, are caused by human activity. With the production of artificial fertilizers by means of the Haber-Bosch process, humans have already extracted more nitrogen out of the atmosphere than has ever circulated through the land ecosystems.48
But our space requirements extend well beyond the land surface. The Holocene oceans seemed inexhaustible, a boundless global ecosystem, 1.3 billion cubic kilometers in size, many times larger than all land habitats put together.49 In a very short time, humanity’s impact on the oceans has also become far-reaching, stretching thousands of feet down where atomic waste was dumped, new mining projects (such as the one off the coast of Papua, New Guinea) are pursued and new oil wells