Unprecedented energy consumption is leaving a permanent stain on planetary history

A new study co-authored by three professors at the University of Leicester’s School of Geography, Geology and the Environment argues that the speed and scale of human energy consumption has pushed the Earth towards a new geological epoch, the ‘Anthropocene’.

The paper, led by Professor Jaia Syvitski from the University of Colorado and published in Nature Communications Earth and Environment, documents the natural drivers of environmental change throughout the past 11,700 years and the dramatic human-caused shifts that have occurred since 1950.

The word Anthropocene follows the naming convention for assigning geologically defined durations of time and has come to embody the present time during which humans are dominating planetary-scale Earth systems.

Professor Colin Waters, Honorary Professor in the Department of Geology at the University of Leicester and Chair of the Anthropocene Working Group says, “This study clearly demonstrates how we humans have developed over time into a global geological force capable of modifying the Earth’s climate, landscape, water and air quality, and biological diversity. Our research shows that the middle of the 20th century is a transformative time in both human and Earth history and supports the narrative that we are living in a new geological epoch, the Anthropocene.”

In the past 70 years, humans have exceeded the energy consumption of the entire preceding 11,700 years, largely through combustion of fossil fuels. This huge increase in energy consumption has allowed for a dramatic increase in human population, industrial activity, pollution, environmental degradation and climate change.

Professor Syvitski from the University of Colorado says, “It takes a lot to change the Earth's system. Even if we were to get into a greener world where we were not burning fossil fuels - the main culprit of greenhouse gases - we would still have a record of an enormous change on our planet.

“We humans collectively got ourselves into this mess, we need to work together to reverse these environmental trends and dig ourselves out of it. Society shouldn't feel complacent. Few people who read the manuscript should come away without emotions bubbling up, like rage, grief and even fear.”

The study documents how:

• Distinct physical, chemical and biological changes to Earth’s rock layers began around the year 1950, with planetary-wide changes altering oceans, rivers, lakes, coastlines, vegetation, soils, chemistry and climate.
• Humans have produced so many millions of tons of plastic each year since the middle of the 20th century that Syvitski suggests microplastics alone are “forming a near-ubiquitous and unambiguous marker of Anthropocene”.
• Between 1952 and 1980, humans set off more than 500 thermonuclear explosions above ground as part of global nuclear weapons testing, which have left a “clear signature” of human-caused radionuclides—atoms with excess nuclear energy—on or near the surface of the entire planet.
• Since about 1950, humans have also doubled the amount of fixed nitrogen on the planet through industrial production for agriculture, created a hole in the ozone layer through the industrial-scale release of chlorofluorocarbons (CFCs), released enough greenhouse gasses from fossil fuels to cause planetary level climate change, created tens of thousands more synthetic mineral-like compounds than naturally occur on Earth and caused almost one-fifth of river sediment worldwide to no longer reach the ocean due to dams, reservoirs and diversions.

The study is the result of work by the Anthropocene Working Group (AWG), an interdisciplinary group of scientists analysing the case for making the Anthropocene a new epoch within the official Geological Time Scale, characterised by the overwhelming human impact on the Earth.