Quantcast
Environmental News for a Healthier Planet and Life

Help Support EcoWatch

Geologists: Humans' Mark on the Earth Will Be Detectable Millions of Years From Now

Science
Geologists: Humans' Mark on the Earth Will Be Detectable Millions of Years From Now

Geologists are convinced that humans have left a mark upon the planet that will be detectable millions of years from now.

Long after human civilization has perished, there could be a stratum of fossilized rock and a geological time zone that says: “We were here.” So there is a case for calling the present epoch “the Anthropocene”—probably dating from about 65 years ago.

Evidence of such things as concrete and major road-building will remain for millions of years.

The term Anthropocene derives from the ancient Greek for humankind. And for more than a decade, scientists have been arguing about whether what is officially known as the Holocene epoch of the Quaternary period of the Cenozoic era should be renamed to indicate human impact. There have been arguments in plenty.

Humans have appropriated most of the world’s available fresh water for their own use; as miners, road-makers and city builders, they have become a greater earth-moving force even than wind, water and ice; and they have altered the composition of the atmosphere.

Dramatically Altered

They have also dramatically altered the natural land cover and have pushed into the shadow of extinction an alarming proportion of the other 10 million or so species that share the planet and its resources.

Climate and environmental scientists have frequently invoked the term Anthropocene to highlight the impact of humans on the planet and even started to think about how and when to date the most significant evidence of change.

But Colin Waters, principal mapping geologist at the British Geological Survey and colleagues report in Science journal that they put the question in a different form: to what extent are human actions recorded as measurable signals in geological strata? And would the Anthropocene strata be markedly different from the Holocene that began with the end of the last Ice Age nearly 12,000 years ago?

The answer is, yes: The human geological signature could be discerned, across the planet, in materials that were not available in the same way in any previous epoch. The evidence will be, in every sense, concrete.

Humans have long affected the environment, but recently there has been a rapid global spread of novel materials—including aluminum, concrete and plastics—that are leaving their mark in sediments.

Fossil fuel combustion has dispersed fly ash particles worldwide, pretty well coincident with the peak distribution of the “bomb spike” of radionuclides generated by atmospheric testing of nuclear weapons, Dr. Waters said.

Aluminum is plentiful in the Earth’s crust in compound mineral form, but refined aluminum is a marker of 20th-century human presence. So is concrete. The ancient Romans may have pioneered the use of this crushed and baked version of limestone, but as a universal and ubiquitous building material, it began to appear only in the last 100 years.

The combustion of fossil fuels has distributed soot, heavy metals and aerosols in mixtures and concentrations that had never existed before the commercial power stations, factories, railways and motor cars. And the atmospheric tests in the 1950s and 1960s of atomic and thermonuclear weapons left a series of “spikes” of signature isotopes.

Nitrate Levels

Soil nitrogen and phosphorus levels have doubled in the last century because of agricultural use and even in places where agriculture does not happen the nitrate levels in the lakes of Greenland are higher than at any time in the last 10,000 years.

And if the signature of altered ratios of “natural” materials was not enough, humankind will have left its mark in exotic plastic fabrics gathering in the planet’s oceans at an estimated rate in 2015 of 9 million tons a year.

The precise nomenclature of geological time zones is a convenience largely for professional geologists and palaeontologists. But the researchers do not see their argument as a purely academic one. Names tell us something.

“Quite unlike other subdivisions of geological time, the implications of formalizing the Anthropocene reach well beyond the geological community,” they concluded.

“Not only would this represent the first instance of a new epoch having been witnessed firsthand by advanced human societies, it would be one stemming from the consequences of their own doing.”

YOU MIGHT ALSO LIKE

Will Obama Make Good on His Promise to Reduce the Threat of Nuclear Warfare?

Revolutionizing Battery Storage Key to Fast Tracking Renewables

Leonardo DiCaprio: ‘Revenant’ Drove Home Need to Take Climate Action

Watch 25 Years of Arctic Sea Ice Melt in One Minute

Coast Guard members work to clean an oil spill impacting Delaware beaches. U.S. Coast Guard District 5

Environmental officials and members of the U.S. Coast Guard are racing to clean up a mysterious oil spill that has spread to 11 miles of Delaware coastline.

Read More Show Less

EcoWatch Daily Newsletter

What happened to all that plastic you've put in the recycling bin over the years? Halfpoint / Getty Images

By Dr. Kate Raynes-Goldie

Of all the plastic we've ever produced, only 9% has been recycled. So what happened to all that plastic you've put in the recycling bin over the years?

Read More Show Less

Trending

Plain Naturals offers a wide variety of CBD products including oils, creams and gummies.

Plain Naturals is making waves in the CBD space with a new product line for retail customers looking for high potency CBD products at industry-low prices.

Read More Show Less
Donald Trump and Joe Biden arrive onstage for the final presidential debate at Belmont University in Nashville, Tennessee, on Oct. 22, 2020. JIM WATSON / AFP via Getty Images

Towards the end of the final presidential debate of the 2020 election season, the moderator asked both candidates how they would address both the climate crisis and job growth, leading to a nearly 12-minute discussion where Donald Trump did not acknowledge that the climate is changing and Joe Biden called the climate crisis an existential threat.

Read More Show Less
What will happen to all these batteries once they wear out? Ronny Hartmann / AFP / Getty Images

By Zheng Chen and Darren H. S. Tan

As concern mounts over the impacts of climate change, many experts are calling for greater use of electricity as a substitute for fossil fuels. Powered by advancements in battery technology, the number of plug-in hybrid and electric vehicles on U.S. roads is increasing. And utilities are generating a growing share of their power from renewable fuels, supported by large-scale battery storage systems.

Read More Show Less

Support Ecowatch