The case for the Anthropocene

A single species, humans, has the ability to greatly change all livable parts of Earth. No other species on Earth has ever reached this point.

Geologists have worked out a system of naming large sections of Earth’s time. Thousands of years are called “epochs.” Tens of millions of years are “periods.” Hundreds of millions of years are “eras.” The longest measurements of time are called “eons.” Geologists call our current epoch the Holocene. It started about 10,000 years ago. Back then, after the first ice age, temperatures became stable. The word Holocene comes from Greek roots: holo meaning “whole” and cene meaning “new.” So, Holocene means “wholly new.”

In 2000, the famed chemist Paul Crutzen suggested that we are in a new epoch. He called it the Anthropocene. Crutzen proposed that human domination has changed the planet greatly. So, it’s brought on a new epoch. The name Anthropocene has not been officially adopted. Still, many geologists have begun using it.¹

But why should we care about this name change? It’s the first time scientists have seen one species, humans, having an effect that has greatly changed the planet. Unfortunately, these changes have almost entirely made Earth worse off.

Evidence of change

What kind of evidence could show that humans have begun to dominate and alter the life systems of Earth? The clearest and most familiar is climate change.² Around the world, temperatures on average have risen about 1 degree Celsius. Several serious effects are now occurring. Plants and animals are moving north. Glaciers are melting. Storms and droughts are getting more severe. Weather patterns are changing. Global temperatures are rising. Behind these weather patterns are changes in the Earth’s atmosphere. Scientists can track the changes in layers of rock.

A tiny part of Earth’s atmosphere is made up of “greenhouse gases.” These gases hold in heat reflected from Earth. They do not let heat escape into space. One of these greenhouse gases is carbon dioxide (CO2). During the past million years, CO2 ranged from 180 parts per million (ppm) to 280 ppm. Processes not affected by humans caused this change. At the beginning of human agriculture, the atmospheric concentration of CO2 was 280 ppm. It has risen to the current (2017) level of 405 ppm.³

This rise happened much faster than ever before. It was mostly because humans burned fossil fuels in the last 250 years.

Leading scientists urge us to reduce the concentration of CO2 to 350 ppm. They say it can save our planet. CO2 lingers in the atmosphere for thousands of years. Because of this, we still have CO2 in the air from the 1900s. It continues to contribute to warming. If we are to stop that effect, scientists tell us that global emissions (release) of CO2 must be cut by 50 percent by 2030. It must fall to net zero by the year 2050. However, from 2014-2016 worldwide emissions increased by 1.6 percent. In addition, the increase for 2018 was 2.7 percent. Emissions in both China grew almost 5 percent. In India they rose by more than 6 percent. It reflected the rate at which these countries’ emissions continue to grow as they grow their industry. The United States’ emission increased by 2.5 percent. However, emissions in the European Union decreased by almost 1 percent. The 24th yearly U.N. climate conference took place in 2018. United Nations Secretary-General António Guterres put out a grim warning. He stated, “We are in deep trouble with climate change… Even as we witness devastating climate impacts causing havoc across the world, we are still not doing enough, nor moving fast enough” (Washington Post). Guterres said we could be affecting the climate in ways that are unchangeable. It could cause great destruction.

You might think that natural changes in climate occur slowly over time. However, it doesn’t always happen that way. Sometimes, change speeds up because of feedback cycles. For example, the whiteness of the snow on glaciers in the North and South Poles are important. They reflect some of the sun’s heat back into space. When glaciers at the poles melt, there are less areas of whiteness around to reflect heat. Instead, the heat is absorbed into the land and water. These areas warm, causing more melting of the glaciers. The glaciers then reflect even less heat. The feedback cycle continues.

It’s not only the atmosphere that has been changed by CO2 emissions. The chemistry of the oceans has changed as much of the CO2 in the air dissolves into the oceans. As more CO2 is absorbed into the oceans, it makes the water more acidic. Such activity endangers the life of certain creatures that form calcium shells. The shells break down under too much acid. Runoff from fertilizers and pesticides contributes as well. It causes a strange buildup of harmful algae, called blooms. Overfishing threatens undersea animal worldwide. Our use of plastics is also affecting the oceans and the creatures in it. It also takes fossil fuels to make plastics. The effects of that creation process are also worrying. Both large and very tiny pieces of plastic enter the waterways. So do oil runoff and spills. All become dangerous to life in our oceans, rivers, lakes, and streams.

More than just sea life is at risk. The biodiversity of all parts of the planet is declining faster than usual. Reports say is decline is between a hundred and a thousand times the normal rate. Up to half of all species face extinction in the twenty-first century. Many biologists believe the current extinction will be one of Earth’s six major ones.

Our man-made chemicals are also affecting Earth. These include drugs, pesticides, plastics, and fabrics. Earth is taking in these chemicals. The side effects are unknown right now.

Nuclear energy is another powerful force made by humans. We have tested nuclear bombs and used them. After, radiation has built up. It has also been released from nuclear energy waste and accidents. All these actions have affected the Earth’s environment. The United States first tested and then used nuclear bombs during war in 1945. Several nations have performed similar tests. They aim to get nuclear weapons. In addition, increased levels of radiation on Earth have come from nuclear power waste and fallout from nuclear disasters. Three Mile Island (US), Chernobyl (Ukraine), and Fukushima (Japan) are just a few. Being exposed to radiation can damage or transform the cells of all living organisms.

The evidence above comes from biologists and climate scientists. But geologists have a very specific way of determining historical periods. They look for evidence in the rocks. They also check layers of mud that will become rock. Even in the mud, they are finding evidence of environmental harm. Worldwide sediments contain radiation. It is leftover from atomic bomb testing in the 1960s. Similar evidence exists of chlorine from bomb testing. Mercury has been found in ice-ore samples, related to the burning of coal.

Environmental historians support the claims of geologists. Scholar John McNeill wrote an environmental history of the twentieth-century world. It’s called Something New Under the Sun. In it he asserts that “the human race...has undertaken a gigantic uncontrolled experiment on the Earth.”

Going forward

There are differing opinions about what these changes might bring. Can humans survive them? James Lovelock is an English scientist. He believes that humans can no longer control change. He believes the planet will be returned to some kind of necessary balance. It may not support much human life. According to Lovelock, the best we can do is try to fit our lives to the changes.

Others believe humans are clever enough. Maybe we can find our way out of any tight spot. As a society we can use our group learning to create new ideas. We can build new technologies. In fact, human communities have survived previous disasters. Why can’t we do it again?

Geologists continue to debate other questions: When did the Anthropocene begin? How do we know when we have reached the critical point of human influence on the Earth? Just considering these questions has allowed scientists to examine modern change. Meanwhile, people have to face this life-changing period in the planet’s history. Human decisions made in the near past and in the near future are important. They’ll determine the direction of life on our planet.

Many leading scientists and journalists believe that we have at most 10 years to change our destructive behavior. We must put new technologies into place, they say. Otherwise, our planet’s life-support systems could break down. It will take commitment and new ideas. Most humans on the planet will have to cooperate to safely make these changes.

1 Another possible title for our latest geologic epoch is Capitalocene. It was first suggested by Andreas Malm. He’s a human geographer. Malm focuses on humans’ use of capital (money) and fossil fuels in the industrial age. He says they’ve led toward a new period in history.
2 In fact, geologists have recently determined a new age of the Holocene epoch: The Meghalayan. It began 4,200 years ago with a global drought. The lack of rain lasted 200 years. The Meghalayan began at the same time “as a global, climate-driven cultural event” (Geiger, 5). It’s “the first formal geologic time interval in Earth’s 4.6-billion-year history” to do so, Geiger adds.
3 “The global average atmospheric carbon dioxide in 2017 was 405.0 parts per million (ppm for short)” (Lindsey). It has a “range of uncertainty of plus or minus 0.1 ppm. Carbon dioxide levels today are higher than at any point in at least the past 800,000 years.”