What better time than Earth Day 2021 to talk about something big that is happening to our Earth? The history of our planet (covering about 4.5 billion years) is described using geological time as epochs, eons, eras and ages.
For the last 11,700 years, Earth has been in the Holocene Epoch, beginning at the end of the last ice age, when glaciers that had covered the Earth melted.
Epochs can last for millions of years and are defined by changes in the mineral composition of rock layers and the presence of distinctive fossils. These are the indicators that reflect major climatic change.
Over the past decade, experts in varying fields of science have begun to debate whether we are actually witnessing a new formal geological epoch, the Anthropocene.
The term translates to “Age of Humans,” and there is mounting evidence that human activity rather than natural progress is changing our planet in ways that will continue far into the future through geologic time.
Crucial signs of these changes include our unstable climate and the Earth’s warming. An increase in the release of greenhouse gases, deforestation, agricultural practices, widespread planetary pollution and urbanization and many more human activities underlie these changes.
But to actually document a shift in geologic time, there would have to be detectable markers in rock layers millions of years into the future. This is where the disagreement lies.
Can humans, who have only been around for about 200,000 years, really affect the chemical composition of the fossils and rocks under our feet with their activities? Geologists are looking for proof of this marker, or the “golden spike,” that would demarcate the Holocene from the Anthropocene.
Golden spike candidates range from Britain’s Industrial Revolution beginning in the 18th century and the nuclear weapon test by the United States in July 1946 to plastic pollution and mass extinction events.
Until humans unleashed their destructive powers, mass extinction events were caused by natural causes like volcanic eruptions or asteroids hitting the planet.
The International Commission of Stratigraphy, located in Cambridge, England, is the global governing body that formally names geological eras, associating sedimentary rock layers with a period of time.
Geologists working in stratigraphy spend their time in laboratories, carefully studying cores of dirt or ice and even tree rings to understand the climate history of the Earth.
In the year 2000, a Nobel Prize-winning chemist named Paul Crutzen made stratigraphy more familiar to the world. He said that human activities had altered the fundamental processes of the planet in such a significant way that a new geological epoch, The Anthropocene, had commenced.
The first International Earth Day took place on March 21, 1970, on the vernal equinox of that year. John McConnell, a newspaper publisher, proposed the idea of a global holiday at a UNESCO Conference on the environment in 1969.
He chose the vernal equinox (either March 20 or March 21) when night and day are the same lengths everywhere on the Earth and hoped that people would put aside their differences and recognize their common need to preserve the Earth’s resources.
Then U.N. Secretary-General U Thant signed a proclamation officially establishing the March date as the International Earth Day and made this statement: “May there only be peaceful and cheerful Earth Days to come for our beautiful Spaceship Earth as it continues to spin and circle in frigid space with its warm and fragile cargo of animate life.” The United Nations celebrates this International Earth Day each year by ringing the Peace Bell at U.N. headquarters in New York at the precise moment of the vernal equinox.
Here in the United States, we also celebrate another Earth Day, every April 22.
This second Earth Day was introduced and organized by U.S. Sen. Gaylord Nelson, a Democrat from Wisconsin and environmental activist, who held a nationwide day of environmental education and activism on this date in 1970. He wanted to show other politicians that there was widespread public support for a political agenda centered on environmental issues.
With some dedicated organizers and volunteer college students, the first Earth Day was hugely successful, sparking Earth Day celebrations and clean-ups across the country.
After this first Earth Day, Congress passed a number of important environmental laws, including the Clean Air Act, the Clean Water Act, the Safe Drinking Water Act, wilderness protection legislation and the Environmental Protection Agency was created.
In 1995, Nelson received the Presidential Medal of Freedom from President Bill Clinton for founding Earth Day, raising awareness of environmental issues and nurturing environmental activism. An October 1993 article in American Heritage Magazine proclaimed, “April 22, 1970 Earth Day was…one of the most remarkable happenings in the history of democracy…20 million people demonstrated their support…American politics and public policy would never be the same again.”
These two annual Earth Day celebrations hope to raise awareness and inspire people to take personal action. ”Think Globally, Act Locally” has become the Earth Day mantra, but I think we need to act locally every day. We need to think every day is Earth Day!
President Biden returned the United States to the Paris climate accord on his first day in office. And then he appointed Gavin Schmidt as senior climate adviser to NASA. It’s worth the effort to watch his 2014 TED talk.
So, now that we know something big is afoot on our planet, what to do about it? I like to start by thinking that if humans caused the problem, humans can fix it. But how do we get humans to care about future generations or understand how interconnected we are with all other living things that call the Earth home?
