Aerosol can spraying Earth - Writing in the sky

The following article has been excerpted from The Anthropocene: The Human Era and How it Shapes Our Planet by Christian Schwägerl, a book focusing on our entrance into a new geological epoch, in which human activity is primarily responsible for the changes that occur within Earth’s ecosystems. 

On December 3, 1933, in Amsterdam, Anna Crutzen, a woman in her early twenties, gave birth to a son. She had moved from the Ruhr region in Germany to the capital of the Netherlands, five years earlier, to earn her living as a housekeeper. She had met Josef Crutzen, a young man from Vaals, a small Dutch town on the German border, who was working as a waiter. They fell in love, married in 1932 and soon started a family.

They named their first child Paul Jozef. Nothing at that time indicated that this young boy would literally be responsible for saving the planet from an existential threat and would introduce a groundbreaking idea that would redefine humanity’s place on Earth. Paul did not enjoy a private education like Alexander von Humboldt, nor did he have a botanically minded uncle, as did Charles Darwin.

He grew up in harsh conditions. His mother, who made many sacrifices to care for the family, worked as a steward in a hospital kitchen. His father was regularly unemployed and the family was very poor. In addition, the darkest period of the twentieth century had just begun. Only months before Paul’s birth, Adolf Hitler, the new German chancellor, had seized power in neighbouring Germany. In 1939, just before Paul’s sixth birthday, the German dictator ordered his army to invade Poland, starting the Second World War. Crutzen’s childhood took place in the midst of war. The boy saw German troops march into Amsterdam and commandeer his school. He lived through the Hongerwinter (the famine of 1944–45) in which thousands of Dutch citizens died, including some of his friends. The sight of the Allied bombers that flew from England, across the Netherlands to bomb German cities caused him much distress. His mother’s family lived across the border in the Ruhr, the industrial heartland of Germany, an area laid waste by daily and nightly Allied bombing.

In spite of the wartime conditions, his parents noticed that their son had a special talent for observation and a keen thirst for knowledge. He quickly learned German, French and Flemish, and even memorized dictionaries, just for fun. One bitterly cold winter night, his parents found him sitting, shivering in his pajamas by an open window, gazing up at the sky. Upon seeing snow for the first time, he didn’t feel the cold. Paul often came up with unusual observations. When he first glimpsed a half-moon, he said it was “broken,” and when he saw a man swimming in an Amsterdam canal he insisted for a long time that it was a head without a body. As a teenager, he not only played football but also began reading everything he could find concerning natural science.

After the war, Paul did not want to be a burden to his parents and realized that further education in natural science was beyond his means. There was just enough money for him to attend engineering school. He learned how to build bridges across the many canals in the Netherlands. Then, at the beginning of the 1950s, a life-changing incident occurred. As a child, Paul had always longed to see mountains. Holland is not exactly famous for its high peaks so he often fantasized that the cumulus clouds at which he liked to gaze were mountains.

Now that the war was over, it was possible once again to travel. Using his modest savings, Crutzen managed to get to Switzerland. Had he reached the summit of Mount Pilatus—a well-known mountain near the city of Lucerne—either 10 minutes earlier or 10 minutes later, he might have continued life as a bridge-builder but, just as he reached the summit, a young woman from Finland was starting her descent. She was working as an au pair and was spending her day off learning about her host country. Terttu Soininen walked past the young Dutchman just as he was about to take a photograph of the view and the two of them started talking.

They married a few years later and moved to Sweden, to the small town of Gävle, to be nearer Terttu’s family. Paul found a job as a construction engineer and began building houses instead of bridges. But his taste for knowledge, exploration and understanding had not diminished. The construction job only partly satisfied him. Thus, one day he glanced at a job ad in the newspaper: The Meteorological Institute at the University of Stockholm had an opening for a computer specialist. Admittedly, he hadn’t the slightest experience in either meteorology or computer science, but something told him that he should apply.

The convoluted path leading Paul Crutzen to that café table in a provincial Swedish town, where a newspaper want ad lay before him, was to have momentous consequences—not only for himself but for all of humanity and for the course of Earth’s history.

Rare individuals sometimes change the course of human history on a large scale, in both positive and negative ways. We can think of examples as diverse as Alexander the Great, Jesus Christ, Julius Caesar, Christopher Columbus, and, more recently, Mikhail Gorbachev. But can ordinary human beings also alter the course of Earth’s history?

Yes, they can! A few years before Paul Crutzen was born, an American mechanical engineer and chemist named Thomas Midgley had unknowingly done just that. Midgley worked for the General Motors Chemical Company and had the task of developing new coolants for use in refrigerators and recently-invented air conditioners. Refrigerators had already been through their first design cycle. For all their benefits in helping to preserve food, refrigerator coolants were also volatile, poisonous and combustible. Midgley went in search of alternatives. He and his team produced synthetic compounds that didn’t occur naturally. The substances mixed together in Midgley’s laboratory included carbon, hydrogen, chlorine and fluorine, which, in turn, produced new compounds. One of these substances—chlorofluorocarbon, or CFC—proved to be ideal: it was odourless, non-toxic, highly stable and perfectly suitable for refrigeration. CFCs quickly entered the market under the trade name Freon® and were successfully used all over the world.

In the economic boom of post-WWII, millions of people, especially Americans and Europeans, were suddenly able to afford cars and television sets, kitchen appliances, larger homes and long-distance travel. New supermarkets featured an abundance of foods as agriculture became more mechanized and productive. Chemical factories created new products that were designed to make life easier and more pleasant and that list included Freon. In the 1950s and 1960s, CFC use sharply increased because owning a refrigerator was now taken for granted. However, it wasn’t long before discarded refrigerators dumped in landfills began leaking CFCs into the atmosphere. And because CFCs were odourless and colou ml 2rless, no one noticed what was happening.

Refrigerators in landfill - Writing in the sky

Unwittingly, Thomas Midgley’s invention was causing immense damage to one of the systems most vital to protect life on Earth—a system that had taken hundreds of millions of years to evolve and that had made it possible for humanity to develop in the first place: the ozone layer. At a height of between six and thirty miles up in the Earth’s atmosphere, the ozone layer intercepts most of the sun’s harmful ultraviolet rays. Without the ozone layer, life on Earth, at least on land, would hardly be possible for higher diurnal life forms.

The environmental historian John McNeill later wrote that Midgley “had more impact on the atmosphere than any other single organism in Earth’s history.” In the 1960s, no one knew about the dangers posed by chemicals mixing together, high above Earth’s then three billion inhabitants. CFCs, nitrous oxide, also known as “laughing gas,” another ozone-depleting substance used in farming, and the burning of fossil fuels like coal and petroleum, were causing tremendous damage. Not even Paul Crutzen knew.

In 1958, our Dutch engineer applied for the position of computer specialist at the University of Stockholm’s Meteorological Institute. He got the job because interviewers at the institute believed that he would be a fast learner. This was the young man’s entry into the world of scientific research, the career of his dreams. Not only was he a fast learner in the field of computer science, he also began to attend lectures in mathematics, statistics and meteorology. In 1963 he graduated and began a career as a scientist. Without deliberately planning it, he found himself in one of the hotspots of global environmental research. Among the young professors at Stockholm was Bert Bolin, who went on to co-found the Intergovernmental Panel on Climate Change (IPCC), which he then chaired, from 1988 to 1997.

Crutzen picked an area of research that was relatively new: the chemical processes that take place in Earth’s upper atmosphere. At first, he didn’t realize how significant the gaps in then-current knowledge would prove to be. He was interested in the natural processes and how the protective layer of ozone in the atmosphere constantly renews itself.

Then, his impact on Earth’s future really began: he was one of the very first scientists to ask whether there are chemical processes that harm the ozone layer. Until then, this idea had seemed quite improbable. “The general feeling at the time was that ‘nature is so big and mankind so small,’” says Crutzen today, in retrospect. “Nobody had thought that man-made substances could have a huge effect on stratospheric ozone.”

Crutzen’s initial research into how nitrous oxide, naturally released by soils, might damage the ozone layer, led him to a quite different discovery—that human activity was a threat to the ozone layer.

Ever-increasing quantities of CFC molecules released into the atmosphere from landfills were not the only threat to the ozone layer. At around the same time, aviation engineers were developing large, high-tech nitrous oxide turbines. The United States, France, Great Britain and the Soviet Union had plans to build fleets of Supersonic Transport Aircraft (SSTs) to make it possible for civilians and the military to travel at supersonic speeds. Together with the American chemist Harold Johnston, Crutzen recognized the harm caused by nitrous oxide being released into the stratosphere so he used cool scientific logic to counter the dream that humans should be able to travel like gods to anywhere on Earth in a few hours. At the beginning of the 1970s he did some meticulous calculations to show that the additional nitrous oxide that would be emitted into the atmosphere from a fleet of 500 high-flying SSTs could cause “serious decreases in the total atmospheric ozone layer and changes in the vertical distributions of ozone, at least in certain regions.”

The work of Paul Crutzen and his colleagues sent a new message to the world: humanity had become so powerful and dominant through science, technology and modern lifestyles that we could harm Earth’s protective ozone layer.

Inspired by these warnings, other scientists began to look for additional chemicals that might be changing the ozone layer. Mario Molina and Sherwood Rowland made a discovery in 1974: they established that CFCs are particularly effective in destroying ozone molecules. When Crutzen heard about this groundbreaking work, he immediately contributed his research and calculations showing that the hypotheses of his American colleagues were correct and that in the foreseeable future, 40 percent of the world’s ozone layer might be depleted if the use of CFCs went unchecked. The consequences would be devastating; incidents of skin cancer and genetic mutation would multiply and some regions of the Earth might well become unfit for human life.

There were many objections to the researchers’ theories, especially from the chemical industry that feared for its profits from the sale of CFCs and artificial fertilizers. The “hole” in the ozone layer could be a natural occurrence, critics argued. The harmfulness of CFCs was not proven. It would cause enormous damage to the economy to ban them, since there were no alternatives.

But in the mid-1980s, polar researchers led by Joe Farman returned from Antarctica with data showing that above a continent not populated by humans, the ozone layer was shrinking, especially during the southern hemisphere’s spring and that hazardous ultraviolet rays were reaching the Earth’s surface without hindrance. In 1985 Farman and his team published their results, revealing why the thinning of the ozone layer was over Antarctica, of all places, and not over industrial areas: CFCs adhere particularly well to ice crystals.

The Antarctic explorers’ findings shocked public opinion even more than Rachel Carson’s Silent Spring. Before this, millions of people had associated their refrigerators and freezers with the idea of cold beer and instant pizzas as well as other convenience foods. They sprayed underarm deodorant in the mornings to smell nice at work in the office where, on hot days, they were grateful for air conditioning. Now, all of a sudden, these symbols of modern prosperity were seen in a completely different light. What had been thoughtlessly emptied into the atmosphere was suddenly coming back to haunt, in the form of a “hole” in the ozone layer. The individual actions of millions were a major hazard that threatened human life on Earth, and risked damaging the conditions needed for any terrestrial life.

No matter how aggressively the chemical industry opposed demands made by environmentalists and scientists like Crutzen, Molina and Rowland to ban CFCs, the case was won in 1987. The United Nations drew up the Montreal Protocol, the single most effective international environmental treaty to date, which called for a gradual phase-out of harmful CFCs, used primarily as coolants. In 1997, the Kyoto Protocol was ratified, which aimed to drastically cut carbon dioxide emissions and nitrous oxide (N2O) emissions.

Since then, a slow but constant regeneration of the ozone layer over Antarctica has taken place. In 2012 and 2013, scientists at NASA and the Alfred Wegener Institute in Germany reported that the Antarctic ozone “hole” had become noticeably smaller, for the first time. There is now a chance that the Antarctic ozone “hole” will disappear by 2050—so long as climate change and the extreme durability of CFC molecules do not thwart this.

Currently, researchers are optimistic that the ozone layer is regenerating globally and will be permanently restored. What would have happened if Paul Crutzen had not survived the “hunger winter” in Amsterdam and no one had undertaken research like his?

What if he and his colleagues had not had the academic freedom and sufficient funding to explore the chemistry of the ozone layer without any specific aim?

What if Thomas Midgley had put much more aggressive and faster-acting bromine instead of fluorine into refrigerators and aerosol sprays, right from the beginning, well before reliable instruments for measuring the chemistry of the atmosphere existed?

What if explorers like Farman hadn’t spent long nights and bitterly cold days in the Antarctic to make measurements that, at the time, did not interest anyone?

Questions like these concern Paul Crutzen, who says that he has often asked himself since then: “What other surprises may await us?”

The repair of the ozone layer in the 20th century was dependent on many coincidences. Models show that the ozone layer could have completely disappeared by 2050 had CFC emissions persisted. When Crutzen received the Nobel Prize for Chemistry in 1995, together with Molina and Rowland—or perhaps we should say the “Nobel Prize for Salvaging the Ozone Layer”—he conveyed how utterly humiliating it would have been for humanity to have destroyed the atmospheric layer that protects life on Earth, by the expedience of using aerosol sprays and refrigerators, unaware of the damage being caused. “I can only conclude that mankind has been extremely lucky.”

So, in the 20th century, individuals were indeed making human history but also global history. On the one hand there was Thomas Midgley, the inventor of a substance that was endangering the hundred-million-year-old life-protecting atmospheric layer, and on the other, there were Crutzen, Johnston, Molina, Roland and others who, having recognized what was happening, demanded action. Events high up in the sky were being determined not just by the interaction of molecules, temperature and pressure, but also by the work of chemists synthesizing new substances, and by the scientists who were investigating the effects of these substances. Human work manifest in the form of notes, index cards, laboratory diaries and scientific papers led the way to a new global reality.

For the first time in Earth’s history, the results of human activity could be read, as if written high up in the sky.

Pollution from power plant - Writing in the sky

Paul Crutzen was possessed by his discoveries about the ozone layer. So, back at his desk at the Max Planck Institute, he set about making a list of the ways in which humans were transforming the planet. His list was long—and it grew longer. The more aware Crutzen became of everything that humanity was doing to the Earth, the more a new idea began to form in his mind. He realized that the prevailing view that mankind is miniscule whereas nature is limitless, and that humans only scratch the surface of Earth’s processes, is fundamentally wrong. In his Nobel Prize acceptance speech, he said: “The experiences of the early 1970s had made it utterly clear to me that human activities had grown so much that they could compete and interfere with natural processes.”

This far-reaching notion grew in Crutzen’s scientific mind until it burst onto the scene in early 2000. In February of that year our then 67-year-old scientist went to Cuernavaca, Mexico, to take part in an International Geosphere-Biosphere (IGBP) conference, a forum for Earth system research, hosted by the United Nations. The debate revolved around human impacts on the environment and, time and again, the term for the geological epoch in which we live came up: the Holocene. The Holocene is said to have started 11,700 years ago, as the last Ice Age came to an end. Crutzen remembers the moment thus: “The chairman mentioned the Holocene again and again as our current geological epoch. After hearing that term many times, I lost my temper, interrupted the speaker and remarked that we are no longer in the Holocene. I said that we were already in the Anthropocene. My remark had a major impact on the audience. First there was silence, then people started to discuss this.”

“Scientists from IGBP’s paleo-environment project were reporting on their latest research, often referring to the Holocene, the most recent geological epoch of Earth history, to set the context for their work. Paul, a Vice-Chair of IGBP, was becoming visibly agitated at this usage, and after the term Holocene was mentioned again, he interrupted them. “Stop using the word Holocene. We’re not in the Holocene any more. We’re in the . . . the . . . the . . . (searching for the right word) . . . the Anthropocene!

The word landed among the experts like a time-bomb. Anthropos: the Greek word for “humans,” cene: from kainos, the Greek word for “new,” Anthropocene: the new epoch of humans.

In the coffee break after the session, this new word was virtually the only topic of conversation. Crutzen had just redefined the context in which humanity exists on Earth. With it, he had portrayed everything humans do to and with Earth, normally measured in days, years and centuries, in a whole new way. Crutzen suggested a geological scale, of thousands and even millions of years. He had asserted that human activity has affected the earth, on a geological scale.

The scientists in that conference room in Mexico were profoundly shaken because the Nobel Prize Laureate for chemistry—one of the most often cited natural scientists in the world—was not only describing the past with this new term (something to which geologists are accustomed) but he was also redefining and connecting to the future of a world that is only just emerging: a new Earth sculpted by humans.

From the perspective of the Anthropocene, the ozone layer story will be just one of a hundred or a thousand ways in which humans are fundamentally altering this planet, 4.6 billion years after its formation.

Christian Schwägerl is an award-winning journalist who reports on the environment, agricultural development and politics internationally. Since 2012, Schwägerl has helped initiate two major cultural endeavours around the Anthropocene in Germany: The Anthropocene Project, at the federally funded House of World Cultures in Berlin, and a special exhibition at the German Technology Museum in Munich. He is the author of several books, including The Anthropocene (Synergetic Press, 2014).

Excerpted from The Anthropocene by Christian Schwägerl, copyright © 2014. Used with permission of Synergetic Press,

image 1: Spray Polluting via Shutterstock; image 2: Appliances at the landfill via Shutterstock; image 3: Big pollution via Shutterstock