Are We Living in a New Geologic Epoch?
Written by Nancy Atkinson
Have humans changed our planet Earth so much in the past 200 years that we are now living in a new geological age? A group of geologists believes this is the case. They have formally proposed designating a new geologic epoch, the Anthropocene, which would encompass the past 200 years or so of geologic history. The action is appropriate, they say, because during the past 2 centuries, human activity has caused most of the major changes in Earth's topography and climate.
Like rings in a tree, each layer in Earth’s geologic record reflects the conditions of the time it was deposited and offers a glimpse into Earth's past. In this geologic history that is written in the rocks and soil of our planet, researchers have differentiated the layers into classifications of time called eons, eras, periods, epochs, and ages that reflect characteristic conditions. For example, the Carboniferous period, which lasted from 360 million to 300 million years ago, is known for the vast deposits of coal that formed from jungles and swamps. Even some of the longer stretches have been named based on biology, such as the Paleozoic ("old life") and the Cenozoic ("recent life").
Earth has been has always been subject to the same kinds of physical forces–wind, waves, sunlight–throughout the planet's existence. But the life that has arisen on the planet has had a much more varied impact such as the rise of plants that has shaped the planet in dramatic ways. But in the past 200 years, ever since the human population has reached 1 billion, our influences have affected the composition of Earth's strata, altering the physical and chemical nature of ocean sediments, ice cores and surface deposits. Some of these influences are the use of fossil fuels and the growth of large cities.
British Geologist Jan Zalasiewicz and several colleagues argue that the International Commission on Stratigraphy should officially mark the end of the current epoch. That would be the Holocene ("entirely recent"), which started after the end of the last ice age, about 10,000 years ago. The new epoch would be the Anthropocene.
The evidence the geologists cite include the dramatic increase in lead concentration in the soil and water since about 1800 and the increase of carbon dioxide in the atmosphere. They claim that human processes now vastly outpace the equivalent natural forces. "A reasonable case can be made for the Anthropocene as a valid formal unit," Zalasiewicz says.
The argument has merit, says American geologist Richard Alley. "In land, water, air, ice, and ecosystems, the human impact is clear, large, and growing," he says. "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."
Original News Source: AAAS ScienceNow
Filed under: Earth
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January 29th, 2008 at 7:23 am
[...] Are We Living in a New Geologic Epoch? Have humans changed our planet Earth so much in the past 200 years that we are now living in a new geological age? A group of geologists believes this is the case. They have formally proposed designating a new geologic epoch, the Anthropocene, which would encompass the past 200 years or so of geologic history. The action is appropriate, they say, because during the past 2 centuries, human activity has caused most of the major changes in Earth's topography and climate. (more…) [...]
January 29th, 2008 at 7:49 am
It seems that we have changed things, but I don't know how this epoch would ever end. It seems like what is happening is the beginning of a new dynamic period for the earth's features, and this period might be better described as the end of the epochs, as far as the record of history goes. I would guess that in 1000 years, the changes that we have made over the past 200 years would be obliterated.
January 29th, 2008 at 9:22 am
Oooh, from here to Trantor… sadly.
January 29th, 2008 at 12:35 pm
I wonder if any of the other epochs were declared after only 200 years of data.
January 29th, 2008 at 1:47 pm
I have not seen any data collected by the research conducted on this topic, but I do partly agree that we have entered a new geologic age. One thing to keep in mind, is even in 1000 years if humanity ceases to exist, geologic time will still carry on. We may not be around to define new eras, but that doesn't mean this planet won't define those eras for itself. It most certainly can exist without us (it has before), and it doesn't need names or man-made titles to do so.
January 29th, 2008 at 1:48 pm
David, those eons, eras, periods, epochs, etc. were named much longer after they existed. We are talking about approximately 4.6 billion years of geologic time. We have not been around for that long.
January 29th, 2008 at 2:02 pm
Because the naming of epochs, eras and such are so arbitrary as far as having any real meaning, we should leave it up to the people (or other dominate life forms) to name it. If you're living in a geologic period, you are too close to see the changes that will really make any sense to the future. So we should leave it up to them to name it. If we really did make a big impact, then they will have the totality of evidence to make that distinction.
January 29th, 2008 at 2:20 pm
[...] human species has had on the geological record as a new geological epoch (Universe Today also has a good article up on this topic). The concept of the Anthropocene, as originally suggested by Nobel Prize-winning chemist Paul [...]
January 29th, 2008 at 2:28 pm
Davis said: "I wonder if any of the other epochs were declared after only 200 years of data."
- The Hadean, which is the eon during the Earth's formation, and around 800 million years long, has no direct evidence apart from a few zircon crystals. If you can infer an entire eon with a few crystals worth of evidence (and a lot of extra-terrestrial data from the analysis of meteorites and other geochemical markers), then the last 200 years worth of data, which is exceptional, should be more than enough to define a mere epoch.
As Clint said, it's pretty arbitrary.
January 29th, 2008 at 6:17 pm
Some political leader needs to mention overpopulation.
January 30th, 2008 at 5:53 am
I smell a political agenda behind this proposed epoch. Geologically, 200 years is hardly a blip on the screen. This is another attempt to emphasize how badly we need to change our polluting ways. I agree with the need to change how we deal with our environment, but heartily disagree in using the geologic field of science to carry a banner for social and political change. My guess is this is a jump on the band wagon to leverage funding based on the current sociological trends.
January 30th, 2008 at 9:15 am
I would definitely agree that humans are now the biggest environmental factor on earth so i would agree with this.
I dont think there is a strong political message in this, its more a statement of fact.
January 30th, 2008 at 10:04 am
I think Johnny Blues is right on!
January 30th, 2008 at 1:31 pm
Johnny Blues makes an excellent point…there is big money (political funding) to be made by people/businesses helping us stop our polluting ways. Follow the money….
Also, humans are not biggest environmnetal factor on earth as Lawrence states…we have some empact for sure. But it seems we've forgotten about the biggest influence…The Sun!
January 30th, 2008 at 8:05 pm
We can't stop the Sun. We can decrease population growth.
January 31st, 2008 at 5:26 am
Just look. The topic has naturally progressed into the field of sociology. Geology epochs are about what was, not what will be.
January 31st, 2008 at 9:11 am
The topic of the article is how humans have changed Earth. That's "what was." Predicting the end of the Sun's life is "what will be." Is that not still science? Predicting the effects of overpopulation of an intelligent species is also science. A two percent rise in population of Earth every year would give us as many people as atoms in the Solar System by the year 4000 (approximately). Of course that won't happen (either we can solve it the humane way or nature will solve it for us–a mixture of science and sociology).
January 31st, 2008 at 2:47 pm
I also agree with Johnny Blues, that this is politically motivated. I believe the whole "global warming" threat is politically motivated. Follow the money (as "Deep Throat' said). Researchers need financing and then we have a global warming crisis. In the 70's I remember the scientist created the story we were heading for another "ice age". Don't get me wrong, I'm not anti-science, just anti-political agenda. As far as "global warming", humans are not the major cause. Yes we are a contributor, but it's minor. Take a look at the Greenland's ice core samples. From now until around 50,000 years ago (or longer), is shows the last 10,000 years have been very small and stable swings in temperature. Before 10,000 years the temperatures varied wildly and in short periods of time (some within 100 years). And there were no humans at that time. This shows me that humans, if they do effect global temperatures, it is minor. But I do think we should all do whatever we can to control the polution we create, and keep it as low as possible. That only makes sense.
January 31st, 2008 at 4:54 pm
Completely backwards, Clint. President Bush's lawyers (not scientists) edit their science advisers when it comes to global warming–don't want anyone to think it's really happening.
I hold all the world's scientists' (USA included) opinions more highly than the Bush lawyers' politics.
P.S. 'Deep Throat' never said, "Follow the money." Hal Holbrook did.
February 1st, 2008 at 5:44 am
Lets focus back on the science of geology, screw politics. Ask yourself this – What other epoch has been given an official naming when it had only a beginning, but no discernible end? Its for geologists in the future to name the current "epoch", once this proposed period of time ends where a new epoch will begin, If this Epoch Of Man's Crappola just continues, there will be no naming it. We'll just all die wishing another epoch was coming.
February 1st, 2008 at 1:12 pm
How right you are Johnny Blues. Now geolgists will need more govt, grants to support their bold assertion. Failure to agree with them makes one a heretic of the new world religion of saving the earth from ourselves. Scientists seem to be the new high priests of our time. Lawrence (above) believes that the geologists are making "more or less" statement of fact. How does one name an epoch BEFORE it comes to pass with such conviction?
February 1st, 2008 at 11:34 pm
Who was around to name the epochs before this, Johnny Blues? But the bigger question is who are these fawning little scientist bashers who are licking your hand?
February 1st, 2008 at 11:58 pm
Johnny Blues and Mike are belittling the world's geologists, which leads me to believe they are not geologists. If this is so, how can they criticize something they know so little about? I don't know much about it either–but I will trust the great majority of scientists' theories over these two neo-cons' politically driven fantasies. "Who's being political?" is the right question.
February 5th, 2008 at 12:15 pm
I think that Johnny Blues has multiple personalities.
February 13th, 2008 at 12:36 am
[...] Today Nancy Atkinson gives us a nice, neutral rundown at Universe Today: Are We Living in a New Geologic Epoch?; The evidence the geologists cite include the dramatic increase in lead concentration in the soil [...]