Scientists: Humans Force Earth into New Geologic Epoch

[Trumplestiltskin 5,791]

Robert Roy Britt

LiveScience Managing Editor

LiveScience.com

Sun Jan 27, 1:46 PM ET

Humans have altered Earth so much that scientists say a new epoch in the planet's geologic history has begun. Say goodbye to the 10,000-year-old Holocene Epoch and hello to the Anthropocene.

Among the major changes heralding this two-century-old man-made epoch:

Vastly altered sediment erosion and deposition patterns.

Major disturbances to the carbon cycle and global temperature.

Wholesale changes in biology, from altered flowering times to new migration patterns.

Acidification of the ocean, which threatens tiny marine life that forms the bottom of the food chain.

The idea, first suggested in 2000 by Nobel Prize-winning chemist Paul Crutzen, has gained steam with two new scientific papers that call for official recognition of the shift.

In the February issue of the journal GSA Today, a publication of the Geological Society of America, Jan Zalasiewicz and Mark Williams of the University of Leicester and colleagues at the Geological Society of London argue that industrialization has wrought changes that usher in a new epoch.

Scientists of the future will have no trouble deciding if the proposal was timely. All they'll need to do is dig into the planet and examine its stratigraphic layers, which reveal a chronology of the changing conditions that existed as each layer is created. Layers can reflect volcanic upheaval, ice ages or mass extinctions.

"Sufficient evidence has emerged of stratigraphically significant change (both elapsed and imminent) for recognition of the Anthropocene — currently a vivid yet informal metaphor of global environmental change — as a new geological epoch to be considered for formalization by international discussion," Zalasiewicz's team writes.

The paper calls on the International Commission on Stratigraphy to officially mark the shift.

In a separate paper last month in the journal Soil Science, researchers focused on soil infertility alone as a reason to dub this the Anthropocene Age. (The term "age" is sometimes used interchangeably with "epoch" or to indicate a transition period between epochs.)

As an example, they said, agriculture in Africa "has so degraded regional soil fertility that the economic development of whole nations will be diminished without drastic improvements of soil management."

"With more than half of all soils on Earth now being cultivated for food crops, grazed, or periodically logged for wood, how to sustain Earth’s soils is becoming a major scientific and policy issue," said Duke University soil scientist Daniel Richter.

Richter's work was supported by the National Science Foundation, the U.S. Department of Agriculture, the Andrew W. Mellon Foundation.

Origin of a term

Earth's 4.5-billion-year history is divided into major eras, then periods and finally epochs. The Holocene Epoch began after the last Ice Age.

As early as the late 1800s scientists were writing about man's wholesale impact on the planet and the possibility of an "anthropozoic era" having begun, according to Crutzen, who is credited with coining the term Anthropocene (anthropo = human; cene = new) back in 2000. That year, Crutzen and a colleague wrote in the scientific newsletter International Geosphere-Biosphere Programme about some of the dramatic changes:

"Urbanization has ... increased tenfold in the past century. In a few generations mankind is exhausting the fossil fuels that were generated over several hundred million years."

Up to half of Earth's land has been transformed by human activity, wrote Crutzen and Eugene F. Stoermer of the University of Michigan. They also noted the dramatic increase in greenhouse gases and other chemicals and pollutants humans have introduced into global ecosystems.

The epochal idea has merit, according to geologist Richard Alley of Pennsylvania State University.

"In land, water, air, ice, and ecosystems, the human impact is clear, large, and growing,"Alley told ScienceNow, an online publication of the American Association for the Advancement of Science. "A geologist from the far distant future almost surely would draw a new line, and begin using a new name, where and when our impacts show up."

http://news.yahoo.com/s/livescience/200801...ewgeologicepoch

[Mags 112]

That was really interesting, 6, thanks for posting it.

[Trumplestiltskin 5,791]

Its definitely more revealing than the ten-a-penny articles about carbon emission GW - it does at least shows that there is a bigger picture to consider.

[Mags 112]

Its definitely more revealing than the ten-a-penny articles about carbon emission GW - it does at least shows that there is a bigger picture to consider.

Exactly. Regardless of whether GW exists or not, we humans have had a HUGE effect on this world and what we have done will be there to see forever. Unless the Earth explodes and goes boom, of course.

[Trumplestiltskin 5,791]

Its definitely more revealing than the ten-a-penny articles about carbon emission GW - it does at least shows that there is a bigger picture to consider.

Exactly. Regardless of whether GW exists or not, we humans have had a HUGE effect on this world and what we have done will be there to see forever. Unless the Earth explodes and goes boom, of course.

I think all these things contribute to some sort of climate change - you can't alter the ecology of half the land on the planet without expecting some sort of unforseen environmental impacts. Desertification and declining soil qualities are already affecting many people directly and are symptoms of a larger, broader change in the environment of our planet (one that includes GW). In short, for all the talk about carbon emissions - its not just about that. Intensive farming and deforestation have been proven to adversely impact local environments on a massive scale, so big picture - its not beyond the realm of implausibility that these activities have further reaching consequences as well.

[Hilarious Clinton 452]

The earth has always changed and always will.

[Trumplestiltskin 5,791]

The earth has always changed and always will.

What they're saying is that this new epoch marks the point where the Earth is showing numerous environmental and geological changes resulting from human activities.

[Hilarious Clinton 452]

The earth has always changed and always will.

What they're saying is that this new epoch marks the point where the Earth is showing numerous environmental and geological changes resulting from human activities.

I don't buy it.

[Trumplestiltskin 5,791]

The earth has always changed and always will.

What they're saying is that this new epoch marks the point where the Earth is showing numerous environmental and geological changes resulting from human activities.

I don't buy it.

Why?

[Trumplestiltskin 5,791]

Exactly. Regardless of whether GW exists or not, we humans have had a HUGE effect on this world and what we have done will be there to see forever. Unless the Earth explodes and goes boom, of course.

Actually this is a pretty read about that. Some parts of the planetary ecology would recover pretty quickly if humanity disappeared overnight.

In The World Without Us, Alan Weisman offers an utterly original approach to questions of humanity’s impact on the planet: he asks us to envision our Earth, without us.

In this far-reaching narrative, Weisman explains how our massive infrastructure would collapse and finally vanish without human presence; which everyday items may become immortalized as fossils; how copper pipes and wiring would be crushed into mere seams of reddish rock; why some of our earliest buildings might be the last architecture left; and how plastic, bronze sculpture, radio waves, and some man-made molecules may be our most lasting gifts to the universe.

The World Without Us reveals how, just days after humans disappear, floods in New York’s subways would start eroding the city’s foundations, and how, as the world’s cities crumble, asphalt jungles would give way to real ones. It describes the distinct ways that organic and chemically treated farms would revert to wild, how billions more birds would flourish, and how cockroaches in unheated cities would perish without us. Drawing on the expertise of engineers, atmospheric scientists, art conservators, zoologists, oil refiners, marine biologists, astrophysicists, religious leaders from rabbis to the Dali Lama, and paleontologists---who describe a prehuman world inhabited by megafauna like giant sloths that stood taller than mammoths---Weisman illustrates what the planet might be like today, if not for us.

From places already devoid of humans (a last fragment of primeval European forest; the Korean DMZ; Chernobyl), Weisman reveals Earth’s tremendous capacity for self-healing. As he shows which human devastations are indelible, and which examples of our highest art and culture would endure longest, Weisman’s narrative ultimately drives toward a radical but persuasive solution that needn't depend on our demise. It is narrative nonfiction at its finest, and in posing an irresistible concept with both gravity and a highly readable touch, it looks deeply at our effects on the planet in a way that no other book has.

[MissStacey 1]

My biggest concern is- how is this going to affect the ducks?

[Ban Hammer 13,346]

My biggest concern is- how is this going to affect the ducks?

what no love for canada's biggest export?

[SteveLaura 0]

My biggest concern is- how is this going to affect the ducks?

Oh, you're good... *nods sagely*

[HAL 9000 96]

I think people here will come to start accepting scientific findings like this when they stop equating geological time with human time. Naturally ocurring epoch changes take upwards of human eons to fully transition. This artificail epoch change has happened in a jiffy.

[almaty 19]

My biggest concern is- how is this going to affect the ducks?

mine is..the noble burro.......